User:Abyssal/Portal Prehistory of North America

Selected articles about prehistoric North America
1

Acrocanthosaurus (/ˌækroʊˌkænθoʊˈsɔːrəs/ ak-rə-KAN-thə-SOR-əs; meaning "high-spined lizard") is a genus of theropod dinosaur that existed in what is now North America during the Aptian and early Albian stages of the Early Cretaceous. Like most dinosaur genera, Acrocanthosaurus contains only a single species, A. atokensis. Its fossil remains are found mainly in the U.S. states of Oklahoma, Texas, and Wyoming, although teeth attributed to Acrocanthosaurus have been found as far east as Maryland.

Acrocanthosaurus was a bipedal predator. As the name suggests, it is best known for the high neural spines on many of its vertebrae, which most likely supported a ridge of muscle over the animal's neck, back and hips. Acrocanthosaurus was one of the largest theropods, approaching 12 meters (40 ft) in length, and weighing up to 6.2 tonnes (6.8 short tons). Large theropod footprints discovered in Texas may have been made by Acrocanthosaurus, although there is no direct association with skeletal remains.

Recent discoveries have elucidated many details of its anatomy, allowing for specialized studies focusing on its brain structure and forelimb function. Acrocanthosaurus was the largest theropod in its ecosystem and likely an apex predator which possibly preyed on large sauropods and ornithopods. (see more...)

2

Albertosaurus (/ælˌbɜːrtoʊˈsɔːrəs/; meaning "Alberta lizard") is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, about 70 million years ago. The type species, A. sarcophagus, was apparently restricted in range to the modern-day Canadian province of Alberta, after which the genus is named. Scientists disagree on the content of the genus, with some recognizing Gorgosaurus libratus as a second species.

As a tyrannosaurid, Albertosaurus was a bipedal predator with tiny, two-fingered hands and a massive head with dozens of large, sharp teeth. It may have been at the top of the food chain in its local ecosystem. Although relatively large for a theropod, Albertosaurus was much smaller than its more famous relative Tyrannosaurus, probably weighing less than 2 metric tons.

Since the first discovery in 1884, fossils of more than thirty individuals have been recovered, providing scientists with a more detailed knowledge of Albertosaurus anatomy than is available for most other tyrannosaurids. The discovery of 26 individuals at one site provides evidence of pack behaviour and allows studies of ontogeny and population biology which are impossible with lesser-known dinosaurs. (see more...)

3

Allosaurus is a genus of large theropod dinosaur that lived 155 to 150 million years ago during the late Jurassic period (Kimmeridgian to early Tithonian). The name "Allosaurus" means "different lizard". The first fossil remains that can definitely be ascribed to this genus were described in 1877 by paleontologist Othniel Charles Marsh. As one of the first well-known theropod dinosaurs, it has long attracted attention outside of paleontological circles.

Allosaurus was a large bipedal predator. Its skull was large and equipped with dozens of large, sharp teeth. It averaged 8.5 m (28 ft) in length, though fragmentary remains suggest it could have reached over 12 m (39 ft). It is classified as an allosaurid, a type of carnosaurian theropod dinosaur. The genus has a complicated taxonomy, and includes an uncertain number of valid species, the best known of which is A. fragilis. The bulk of Allosaurus remains have come from North America's Morrison Formation, with material also known from Portugal and possibly Tanzania.

As the most abundant large predator in the Morrison Formation, Allosaurus was at the top of the food chain, probably preying on contemporaneous large herbivorous dinosaurs and perhaps even other predators. Potential prey included ornithopods, stegosaurids, and sauropods. Some paleontologists interpret Allosaurus as having had cooperative social behavior, and hunting in packs, while others believe individuals may have been aggressive toward each other. It may have attacked large prey by ambush, using its upper jaw like a hatchet. (see more...)

4

The Chicxulub crater (/ˈtʃiːkʃəluːb/; Mayan pronunciation: [tʃʼikʃuluɓ]) is a prehistoric impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is located near the town of Chicxulub, after which the crater is named. The age of the Chicxulub asteroid impact and the Cretaceous–Paleogene boundary (K–Pg boundary) coincide precisely. The crater is more than 180 kilometres (110 mi) in diameter and 20 km (12 mi) in depth, making the feature one of the largest confirmed impact structures on Earth; the impacting bolide that formed the crater was at least 10 km (6 mi) in diameter. Evidence for the impact origin of the crater includes shocked quartz, a gravity anomaly, and tektites in surrounding areas. The age of the rocks marked by the impact shows that this impact structure dates from roughly 66 million years ago, the end of the Cretaceous period, and the start of the Paleogene period. The impact associated with the crater is thus implicated in the Cretaceous–Paleogene extinction event, including the worldwide extinction of non-avian dinosaurs. This conclusion has been the source of controversy. In March 2010, 41 experts from many countries reviewed the available evidence: 20 years worth of data spanning a variety of fields. They concluded that the impact at Chicxulub triggered the mass extinctions at the K–Pg boundary. (see more...)

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The Columbian mammoth (Mammuthus columbi) was a species of mammoth that inhabited North America as far north as the northern United States and as far south as Costa Rica during the Pleistocene epoch. The Columbian mammoth evolved from the steppe mammoth, which entered North America from Asia about 1.5 million years ago. The closest extant relative of the Columbian and other mammoths is the Asian elephant.

Reaching 4 m (13 ft) at the shoulders and 8–10 tonnes (18,000–22,000 lb) in weight, the Columbian mammoth was one of the largest species of mammoth. It had long, curved tusks and four molars, which were replaced six times during the lifetime of an individual. It most likely used its tusks and trunk like modern elephants—for manipulating objects, fighting, and foraging. Bones, hair, dung and stomach contents have been discovered, but no preserved carcasses are known. The Columbian mammoth preferred open areas, such as parkland landscapes, and fed on sedge, grass, and other plants.

Columbian mammoths coexisted with Palaeoamericans, who hunted them for food, used their bones for making tools, and depicted them in ancient art. Columbian mammoth remains have been found in association with Clovis culture artefacts. The Columbian mammoth disappeared at the end of the Pleistocene around 11,000 years ago, most likely as a result of habitat loss caused by climate change, hunting by humans, or a combination of both. (see more...)

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Daspletosaurus (/dæsˌpliːtoʊˈsɔːrəs/ das-PLEET-o-SAWR-əs; meaning "frightful lizard") is a genus of tyrannosaurid theropod dinosaur that lived in western North America between 77 and 74 million years ago, during the Late Cretaceous Period. Fossils of the only named species (D. torosus) were found in Alberta, although other possible species from Alberta and Montana await description. Including these undescribed species makes Daspletosaurus the most species-rich genus of tyrannosaur.

Daspletosaurus is closely related to the much larger and more recent Tyrannosaurus. Like most known tyrannosaurids, it was a multi-tonne bipedal predator equipped with dozens of large, sharp teeth. Daspletosaurus had the small forelimbs typical of tyrannosaurids, although they were proportionately longer than in other genera.

As an apex predator, Daspletosaurus was at the top of the food chain, probably preying on large dinosaurs like the ceratopsid Centrosaurus and the hadrosaur Hypacrosaurus. In some areas, Daspletosaurus coexisted with another tyrannosaurid, Gorgosaurus, though there is some evidence of niche differentiation between the two. While Daspletosaurus fossils are rarer than other tyrannosaurids, the available specimens allow some analysis of the biology of these animals, including social behavior, diet, and life history. (see more...)

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Deinonychus is a genus of carnivorous dromaeosaurid coelurosaurian dinosaurs. There is one described species, Deinonychus antirrhopus. This species, which could grow up to 3.4 metres (11 ft) long, lived during the early Cretaceous Period, about 115–108 million years ago (from the mid-Aptian to early Albian stages). Fossils have been recovered from the U.S. states of Montana, Wyoming, and Oklahoma, in rocks of the Cloverly Formation and Antlers Formation, though teeth that may belong to Deinonychus have been found much farther east in Maryland.

Paleontologist John Ostrom's study of Deinonychus in the late 1960s revolutionized the way scientists thought about dinosaurs, leading to the "dinosaur renaissance" and igniting the debate on whether dinosaurs were warm-blooded or cold blooded. Before this, the popular conception of dinosaurs had been one of plodding, reptilian giants. Ostrom noted the small body, sleek, horizontal posture, ratite-like spine, and especially the enlarged raptorial claws on the feet, which suggested an active, agile predator. The etymology "terrible claw" refers to the unusually large, sickle-shaped talon on the second toe of each hind foot. The fossil YPM 5205 preserves a large, strongly curved ungual. Ostrom looked at crocodile and bird claws and reconstructed the claw for YPM 5205 as over 150 millimetres (5.9 in) long.

In both the Cloverly and Antlers formations, Deinonychus remains have been found closely associated with those of the ornithopod Tenontosaurus. Teeth discovered associated with Tenontosaurus specimens imply they were hunted, or at least scavenged upon, by Deinonychus. (see more...)

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Deinosuchus is an extinct genus related to the alligator that lived 80 to 73 million years ago (Ma), during the late Cretaceous period. The name translates as "terrible crocodile" and is derived from the Greek. Although Deinosuchus was far larger than any modern crocodile or alligator, with the largest adults measuring 10.6 m (35 ft) in total length, its overall appearance was fairly similar to its smaller relatives. It had large, robust teeth built for crushing, and its back was covered with thick hemispherical osteoderms. One study indicated Deinosuchus may have lived for up to 50 years, growing at a rate similar to that of modern crocodilians, but maintaining this growth over a much longer time. Deinosuchus fossils have been found in 10 US states, including Texas, Montana, and many along the East Coast. Fossils have also been found in northern Mexico. It lived on both sides of the Western Interior Seaway, and was an opportunistic apex predator in the coastal regions of eastern North America. Deinosuchus reached its largest size in its western habitat, but the eastern populations were far more abundant. Deinosuchus was probably capable of killing and eating large dinosaurs. It may have also fed upon sea turtles, fish, and other aquatic and terrestrial prey. (see more...)

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The Cretaceous–Paleogene extinction event was the mass extinction of three-quarters of Earth's plant and animal species during a geologically brief interval about 66 million years (Ma) ago. A wide range of species perished in the K–Pg extinction, most notably the non-avian dinosaurs. However, other groups that sustained losses or vanished include mammals, pterosaurs, birds, lizards, insects, and plants. In the oceans, the K–Pg extinction devastated the giant marine lizards, plesiosaurs, fishes, ammonites and plankton. It marked the end of the Cretaceous period and with it, the entire Mesozoic Era, opening the Cenozoic Era which continues today. In the geologic record, the K–Pg event is marked by a thin layer of sediment called the K–Pg boundary, which can be found throughout the world in marine and terrestrial rocks. The boundary clay shows high levels of the metal iridium, which is rare in the Earth's crust but abundant in asteroids. It is now generally believed that the K–Pg extinction was triggered by a massive comet/asteroid impact and its catastrophic effects on the global environment, including a lingering impact winter that halted photosynthesis in plants and plankton. However, some scientists maintain the extinction was caused or exacerbated by other factors, such as volcanic eruptions, climate change, and/or sea level change. Whatever the cause, many of the surviving animal groups diversified during the ensuing Paleogene period. Mammals in particular radiated into new forms such as horses, whales, bats, and primates. (see more...)

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Dinosaurs are a diverse group of animals that first appeared during the Triassic period, 231.4 million years ago, and were the dominant terrestrial vertebrates for 135 million years, from the beginning of the Jurassic until the end of the Cretaceous (66 million years ago), when the Cretaceous–Paleogene extinction event led to the extinction of most dinosaur groups. The fossil record indicates that birds evolved from theropod dinosaurs and, consequently, they are considered a subgroup of dinosaurs by many paleontologists. Some birds survived the extinction event and their descendants continue the dinosaur lineage to the present day. Using fossil evidence, paleontologists have identified over 500 distinct genera of non-avian dinosaurs. Dinosaurs are represented on every continent. Some are herbivorous, others carnivorous. While dinosaurs were ancestrally bipedal, many extinct groups included quadrupedal species. Elaborate display structures such as horns or crests are common to all dinosaur groups, and some extinct groups developed skeletal modifications such as bony armor and spines. Evidence suggests that egg laying and nest building are additional traits shared by all dinosaurs. While modern birds are generally small due to the constraints of flight, many prehistoric dinosaurs were large-bodied—the largest sauropod dinosaurs may have achieved lengths of 58 meters (190 feet). Many dinosaurs were quite small: Xixianykus, for example, was only about 50 cm (20 in) long. (see more...)

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Diplodocus is an extinct genus of diplodocid sauropod dinosaur whose fossils were first discovered in 1877 by S. W. Williston. The generic name, coined by Othniel Charles Marsh in 1878, is a Neo-Latin term derived from Greek διπλός (diplos) "double" and δοκός (dokos) "beam", in reference to its double-beamed chevron bones located in the underside of the tail. These bones were initially believed to be unique to Diplodocus; however, they have since then been discovered in other members of the diplodocid family and in non-diplodocid sauropods such as Mamenchisaurus.

This genus of dinosaurs lived in what is now western North America at the end of the Jurassic Period. Diplodocus is one of the more common dinosaur fossils found in the Upper Morrison Formation, a sequence of shallow marine and alluvial sediments deposited about 155 to 148 million years ago, in what is now termed the Kimmeridgian and Tithonian stages (Diplodocus itself ranged from about 154 to 150 million years ago). The Morrison Formation records an environment and time dominated by gigantic sauropod dinosaurs such as Camarasaurus, Barosaurus, Apatosaurus and Brachiosaurus.

Diplodocus is among the most easily identifiable dinosaurs, with its classic dinosaur shape, long neck and tail and four sturdy legs. For many years, it was the longest dinosaur known. Its great size may have been a deterrent to the predators Allosaurus and Ceratosaurus: their remains have been found in the same strata, which suggests they coexisted with Diplodocus. (see more...)

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The Ediacara biota consisted of enigmatic tubular and frond-shaped, mostly sessile organisms that lived during the Ediacaran Period (ca. 635–542 Ma). Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The Ediacara biota radiated in an event called the Avalon explosion, 575 million years ago, after the Earth had thawed from the Cryogenian period's extensive glaciation. The biota largely disappeared contemporaneously with the rapid increase in biodiversity known as the Cambrian explosion. Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian rather than the Ediacaran. For macroorganisms, the Cambrian biota appears to have completely replaced the organisms that populated the Ediacaran fossil record, although relationships are still a matter of debate. Multiple hypotheses exist to explain the disappearance of this biota, including preservation bias, a changing environment, the advent of predators and competition from other life-forms. Breandán MacGabhann argues that the concept of "Ediacara Biota" is artificial and arbitrary as it can not be defined geographically, stratigraphically, taphonomically nor biologically. He points out that 8 particular fossils or groups of fossils considered "Ediacaran" have 5 taphonomic modes (preservation styles), occur in 3 geological periods, and have no phylogenetic meaning as a whole. (see more...)

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Edmontosaurus is a genus of crestless duck-billed dinosaur. The fossils of this animal have been found in rocks of western North America that date from the late Campanian stage to the end of the Maastrichtian stage of the Cretaceous Period, between 73 and 65.5 million years ago. It was one of the last non-avian dinosaurs, and lived shortly before the Cretaceous–Paleogene extinction event. Edmontosaurus was one of the largest hadrosaurids, measuring up to 13 meters (43 ft) long and weighing around 4.0 metric tons (4.4 short tons). It is known from several well-preserved specimens that include not only bones, but in some cases extensive skin impressions and possible gut contents.

Edmontosaurus has a lengthy and complicated taxonomic history dating to the late 19th century. The type species, E. regalis, was named by Lawrence Lambe in 1917, although several other species that are now classified in Edmontosaurus were named earlier. The best known of these is E. annectens, originally named by Othniel Charles Marsh in 1892.

Edmontosaurus was widely distributed across western North America. The distribution of Edmontosaurus fossils suggests that it preferred coasts and coastal plains. It was an herbivore that could move on both two legs and four. Because it is known from several bone beds, Edmontosaurus is thought to have lived in groups, and may have been migratory as well.

(see more...)

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Gorgosaurus is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, between about 76.6 and 75.1 million years ago. Fossil remains have been found in the Canadian province of Alberta and possibly the U.S. state of Montana. Paleontologists recognize only the type species, G. libratus, although other species have been erroneously referred to the genus.

Like most known tyrannosaurids, Gorgosaurus was a bipedal predator weighing more than two metric tons as an adult; dozens of large, sharp teeth lined its jaws, while its two-fingered forelimbs were comparatively small. Gorgosaurus was most closely related to Albertosaurus, and more distantly related to the larger Tyrannosaurus. Some experts consider G. libratus to be a species of Albertosaurus; this would make Gorgosaurus a junior synonym of that genus.

Gorgosaurus lived in a lush floodplain environment along the edge of an inland sea. It was an apex predator (meaning that it was at the top of its food chain), preying upon abundant ceratopsids and hadrosaurs. In some areas, Gorgosaurus coexisted with another tyrannosaurid, Daspletosaurus. Although these animals were roughly the same size, there is some evidence of niche differentiation between the two. Gorgosaurus is the best-represented tyrannosaurid in the fossil record, known from dozens of specimens. These plentiful remains have allowed scientists to investigate its ontogeny, life history and other aspects of its biology. (see more...)

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Lambeosaurus (/ˌlæmbi.oʊˈsɔːrəs/ LAM-bee-ə-SOR-əs; meaning "Lambe's lizard") is a genus of hadrosaurid dinosaur that lived about 76 to 75 million years ago, in the Late Cretaceous period (Campanian) of North America. This bipedal/quadrupedal, herbivorous dinosaur is known for its distinctive hollow cranial crest, which in the best-known species resembled a hatchet. Several possible species have been named, from Canada, the United States, and Mexico, but only the two Canadian species are currently recognized as valid. Lambeosaurus was belatedly described in 1923 by William Parks, over twenty years after the first material was studied by Lawrence Lambe. The genus has had a complicated taxonomic history, in part because small-bodied crested hadrosaurids now recognized as juveniles were once thought to belong to their own genera and species. Currently, the various skulls assigned to the type species L. lambei are interpreted as showing age differences and sexual dimorphism. Lambeosaurus was closely related to the better known Corythosaurus, which is found in slightly older rocks, as well as the less well-known genera Hypacrosaurus and Olorotitan. All had unusual crests, which are now generally assumed to have served social functions like noisemaking and recognition. (see more...)

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Parasaurolophus (/ˌpærəsɔːˈrɒləfəs, -ˌsɔːrəˈloʊfəs/; meaning "near crested lizard" in reference to Saurolophus) is a genus of ornithopod dinosaur that lived in what is now North America during the Late Cretaceous Period, about 76.5–73 million years ago. It was a herbivore that walked both as a biped and a quadruped. Three species are recognized: P. walkeri (the type species), P. tubicen, and the short-crested P. cyrtocristatus. Remains are known from Alberta (Canada), and New Mexico and Utah (United States). The genus was first described in 1922 by William Parks from a skull and partial skeleton found in Alberta. Parasaurolophus was a hadrosaurid, part of a diverse family of Cretaceous dinosaurs known for their range of bizarre head adornments. This genus is known for its large, elaborate cranial crest, which at its largest forms a long curved tube projecting upwards and back from the skull. Charonosaurus from China, which may have been its closest relative, had a similar skull and potentially a similar crest. The crest has been much discussed by scientists; the consensus is that major functions included visual recognition of both species and sex, acoustic resonance, and thermoregulation. It is one of the rarer hadrosaurids, known from only a handful of good specimens. (see more...)

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Stegosaurus (/ˌstɛɡoʊˈsɔːrəs/, meaning "roof lizard" or "covered lizard" in reference to its bony plates) is a genus of armored stegosaurid dinosaur. They lived during the Late Jurassic period (Kimmeridgian to early Tithonian), some 155 to 150 million years ago in what is now western North America. In 2006, a specimen of Stegosaurus was announced from Portugal, showing that they were present in Europe as well. Due to its distinctive tail spikes and plates, Stegosaurus is one of the most recognizable dinosaurs. At least three species have been identified in the upper Morrison Formation and are known from the remains of about 80 individuals. A large, heavily built, herbivorous quadruped, Stegosaurus had a distinctive and unusual posture, with a heavily rounded back, short forelimbs, head held low to the ground and a stiffened tail held high in the air. Its array of plates and spikes has been the subject of much speculation. The spikes were most likely used for defense, while the plates have also been proposed as a defensive mechanism, as well as having display and thermoregulatory functions. Stegosaurus had a relatively low brain-to-body mass ratio. It had a short neck and small head, meaning it most likely ate low-lying bushes and shrubs. It was the largest of all the stegosaurians (bigger than genera such as Kentrosaurus and Huayangosaurus) and, although roughly bus-sized, it nonetheless shared many anatomical features (including the tail spines and plates) with the other stegosaurian genera. (see more...)

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Styracosaurus (/stɪˌrækəˈsɔːrəs/ stə-RAK-ə-SOR-əs; meaning "spiked lizard" from the Ancient Greek styrax/στύραξ "spike at the butt-end of a spear-shaft" and sauros/σαῦρος "lizard") was a genus of herbivorous ceratopsian dinosaur from the Cretaceous Period (Campanian stage), about 75.5 to 75 million years ago. It had four to six long horns extending from its neck frill, a smaller horn on each of its cheeks, and a single horn protruding from its nose, which may have been up to 60 centimetres (2 ft) long and 15 centimetres (6 in) wide. The function or functions of the horns and frills have been debated for many years.

Styracosaurus was a relatively large dinosaur, reaching lengths of 5.5 metres (18 ft) and weighing nearly 3 tons. It stood about 1.8 meters (6 ft) tall. Styracosaurus possessed four short legs and a bulky body. Its tail was rather short. The skull had a beak and shearing cheek teeth arranged in continuous dental batteries, suggesting that the animal sliced up plants. Like other ceratopsians, this dinosaur may have been a herd animal, traveling in large groups, as suggested by bonebeds.

Named by Lawrence Lambe in 1913, Styracosaurus is a member of the Centrosaurinae. One species, S. albertensis, is currently assigned to Styracosaurus. Other species assigned to the genus have since been reassigned elsewhere. (see more...)

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Thescelosaurus (/ˌθɛsɪləˈsɔːrəs/ THESS-il-ə-SOR-əs; ancient Greek θέσκελος-/theskelos- meaning "godlike", "marvelous", or "wondrous" and σαυρος/sauros "lizard") was a genus of small ornithopod dinosaur that appeared at the very end of the Late Cretaceous period in North America. It was a member of the last dinosaurian fauna before the Cretaceous–Paleogene extinction event around 66 million years ago. The preservation and completeness of many of its specimens indicate that it may have preferred to live near streams.

This bipedal ornithopod is known from several partial skeletons and skulls that indicate it grew to between 2.5 and 4.0 meters (8.2 to 13.1 ft) in length on average. It had sturdy hind limbs, small wide hands, and a head with an elongate pointed snout. The form of the teeth and jaws suggest a primarily herbivorous animal. This genus of dinosaur is regarded as a specialized basal ornithopod, traditionally described as a hypsilophodont, but more recently recognized as distinct from Hypsilophodon. Several species have been suggested for this genus. Three currently are recognized as valid: the type species T. neglectus, as well as T. garbanii and T. assiniboiensis.

The genus attracted media attention in 2000, when a specimen unearthed in 1993 in South Dakota, United States, was interpreted as including a fossilized heart. There was much discussion over whether the remains were of a heart. Many scientists now doubt the identification of the object and the implications of such an identification. (see more...)

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Triceratops is a genus of herbivorous ceratopsid dinosaur that first appeared during the late Cretaceous period, about 68 million years ago in what is now North America. It is one of the last known non-avian dinosaur genera, and became extinct in the Cretaceous–Paleogene extinction event 66 million years ago. Its head bore a large bony frill and three horns while its body was massive and four-legged. It shared the landscape with and was probably preyed upon by the fearsome Tyrannosaurus.

The exact placement of the Triceratops genus within the ceratopsid group has been debated by paleontologists. Two species, T. horridus and T. prorsus, are considered valid. Research published in 2010 suggests that the contemporaneous Torosaurus, a ceratopsid long regarded as a separate genus, represents Triceratops in its mature form, a view not accepted by all researchers. Triceratops has been documented by numerous remains collected since the genus was first described in 1889, including at least one complete individual skeleton. Specimens representing life stages from hatchling to adult have been found.

The function of the frills and three distinctive facial horns has long inspired debate. Traditionally these have been viewed as defensive weapons against predators. More recent theories, noting the presence of blood vessels in the skull bones of ceratopsids, find it more probable that these features were primarily used in identification, courtship and dominance displays, much like the antlers and horns of modern reindeer, mountain goats, or rhinoceros beetles. (see more...)

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Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex is commonly abbreviated to T. rex. It lived throughout what is now western North America. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 67 to 66 million years ago. It was among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.

Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hindlimbs, Tyrannosaurus forelimbs were short and bore two clawed digits. Although other theropods rivaled or exceeded Tyrannosaurus rex in size it is one of the largest known land predators in history. The most complete specimen measures up to 12.3 m (40 ft) in length, up to 4 metres (13 ft) tall at the hips, and up to 6.8 metric tons (7.5 short tons) in weight. Tyrannosaurus rex would have been an apex predator, preying upon hadrosaurs, ceratopsians, and possibly sauropods.

More than 50 specimens of Tyrannosaurus rex have been identified, some of which are nearly complete skeletons. Soft tissue and proteins have been reported in at least one of these specimens. The abundance of fossil material has allowed significant research into many aspects of its biology. Its taxonomy is also controversial: some scientists consider Tarbosaurus bataar from Asia to be a second species of Tyrannosaurus and others maintaining Tarbosaurus as a separate genus. (see more...)

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The woolly mammoth (Mammuthus primigenius) was a species of mammoth, the common name for the extinct elephant genus Mammuthus. Its closest extant relative is the Asian elephant. The appearance and behaviour of this species are among the best studied of any prehistoric animal because of the discovery of frozen carcasses in Siberia and Alaska, as well as skeletons, teeth, stomach contents, dung, and depiction from life in prehistoric cave paintings. The mammoth was identified as an extinct species of elephant by Georges Cuvier in 1796. The woolly mammoth was roughly the same size as modern African elephants. Males reached shoulder heights between 2.7 and 3.4 m (9 and 11 ft) and weighed up to 6 tonnes (6.6 short tons). Females averaged 2.6–2.9 metres (8.5–9.5 ft) in height and weighed up to 4 tonnes (4.4 short tons). The woolly mammoth was well adapted to the cold environment during the last ice age. It was covered in fur, with an outer covering of long guard hairs and a shorter undercoat. The colour of the coat varied from dark to light. The ears and tail were short to minimise frostbite and heat loss. It had long, curved tusks and four molars, which were replaced six times during the lifetime of an individual. The diet of the woolly mammoth was mainly grass and sedges. Its habitat was the mammoth steppe, which stretched across northern Eurasia and North America. (see more...)

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Funerary art is any work of art forming, or placed in, a repository for the remains of the dead. The term also encompasses cenotaphs ("empty tombs"), tomb-like monuments which do not contain human remains; and communal memorials to the dead (such as war memorials), which may or may not contain human remains.

Funerary art may serve many cultural functions. It can play a role in burial rites, serve as an article for use by the dead in the afterlife, and celebrate the life and accomplishments of the dead, whether as part of kinship-centred practices of ancestor veneration or as a publicly directed dynastic display. It can also function as a reminder of the mortality of humankind, as an expression of cultural values and roles, and help to propitiate the spirits of the dead, maintaining their benevolence and preventing their unwelcome intrusion into the affairs of the living.

The deposit of objects with an apparent aesthetic intention may go back to the Neanderthals over 50,000 years ago,[1] and is found in almost all subsequent cultures—Hindu culture, which has little, is a notable exception. Many of the best-known artistic creations of past cultures—from the Egyptian pyramids and the Tutankhamun treasure to the Terracotta Army surrounding the tomb of the Qin Emperor, the Mausoleum of Halicarnassus, the Sutton Hoo ship burial and the Taj Mahal—are tombs or objects found in and around them. In most instances, specialized funeral art was produced for the powerful and wealthy, although the burials of ordinary people might include simple monuments and grave goods, usually from their possessions.

An important factor in the development of traditions of funerary art is the division between what was intended to be visible to visitors or the public after completion of the funeral ceremonies.[2] The Tutankhamun treasure, for example, though exceptionally lavish, was never intended to be seen again after it was deposited, while the exterior of the pyramids was a permanent and highly effective demonstration of the power of their creators. A similar division can be seen in grand East Asian tombs. In other cultures, nearly all the art connected with the burial, except for limited grave goods, was intended for later viewing by the public or at least those admitted by the custodians. In these cultures, traditions such as the sculpted sarcophagus and tomb monument of the Greek and Roman empires, and later the Christian world, have flourished. The mausoleum intended for visiting was the grandest type of tomb in the classical world, and later common in Islamic culture. (see more...)

24

Maya stelae (singular stela) are monuments that were fashioned by the Maya civilization of ancient Mesoamerica. They consist of tall sculpted stone shafts and are often associated with low circular stones referred to as altars, although their actual function is uncertain.[3] Many stelae were sculpted in low relief,[4] although plain monuments are found throughout the Maya region.[5] The sculpting of these monuments spread throughout the Maya area during the Classic Period (250–900 AD),[3] and these pairings of sculpted stelae and circular altars are considered a hallmark of Classic Maya civilization.[6] The earliest dated stela to have been found in situ in the Maya lowlands was recovered from the great city of Tikal in Guatemala.[7] During the Classic Period almost every Maya kingdom in the southern lowlands raised stelae in its ceremonial centre.[5]

Stelae became closely associated with the concept of divine kingship and declined at the same time as this institution. The production of stelae by the Maya had its origin around 400 BC and continued through to the end of the Classic Period, around 900, although some monuments were reused in the Postclassic (c. 900–1521). The major city of Calakmul in Mexico raised the greatest number of stelae known from any Maya city, at least 166, although they are very poorly preserved.[8]

Hundreds of stelae have been recorded in the Maya region,[9] displaying a wide stylistic variation.[5] Many are upright slabs of limestone sculpted on one or more faces,[5] with available surfaces sculpted with figures carved in relief and with hieroglyphic text.[4] Stelae in a few sites display a much more three-dimensional appearance where locally available stone permits, such as at Copán and Toniná.[5] Plain stelae do not appear to have been painted nor overlaid with stucco decoration,[10] but most Maya stelae were probably brightly painted in red, yellow, black, blue and other colours.[11]

Stelae were essentially stone banners raised to glorify the king and record his deeds,[12] although the earliest examples depict mythological scenes.[13] Imagery developed throughout the Classic Period, with Early Classic stelae (c. 250–600) displaying non-Maya characteristics from the 4th century onwards, with the introduction of imagery linked to the central Mexican metropolis of Teotihuacan.[14] This influence receded in the 5th century although some minor Teotihuacan references continued to be used.[15] In the late 5th century, Maya kings began to use stelae to mark the end of calendrical cycles.[16] In the Late Classic (c. 600–900), imagery linked to the Mesoamerican ballgame was introduced, once again displaying influence from central Mexico.[17] By the Terminal Classic, the institution of divine kingship declined, and Maya kings began to be depicted with their subordinate lords.[18] As the Classic Period came to an end, stelae ceased to be erected, with the last known examples being raised in 909–910. (see more...)

25

The Norte Chico civilization (also Caral or Caral-Supe civilization)[19] was a complex pre-Columbian society that included as many as 30 major population centers in what is now the Norte Chico region of north-central coastal Peru. Since the early 21st century, it has been established as the oldest known civilization in the Americas and one of the six sites where civilization originated independently in the ancient world. It flourished between 3rd and 1st millennia BC. The alternative name, Caral-Supe, is derived from the Sacred City of Caral[20] in the Supe Valley, a large and well-studied Norte Chico site. Complex society in Norte Chico arose a millennium after Sumer in Mesopotamia, was contemporaneous with the Egyptian pyramids, and predated the Mesoamerican Olmec by nearly two millennia.

In archaeological nomenclature, Norte Chico is a pre-ceramic culture of the pre-Columbian Late Archaic; it completely lacked ceramics and apparently had almost no visual art. The most impressive achievement of the civilization was its monumental architecture, including large earthwork platform mounds and sunken circular plazas. Archaeological evidence suggests use of textile technology and, possibly, the worship of common god symbols, both of which recur in pre-Columbian Andean cultures. Sophisticated government is assumed to have been required to manage the ancient Norte Chico. Questions remain over its organization, particularly the influence of food resources on politics. Some scholars have suggested that Norte Chico was founded on seafood and maritime resources, rather than development of an agricultural cereal and crop surpluses, as has been considered essential to the rise of other ancient civilizations.

Archaeologists have been aware of ancient sites in the area since at least the 1940s; early work occurred at Aspero on the coast, a site identified as early as 1905,[21] and later at Caral further inland.

In the late 1990s Peruvian archaeologists, led by Dr. Ruth Shady Solís, provided the first extensive documentation of the civilization with work at Caral.[22] A 2001 paper in Science, providing a survey of the Caral research,[23] and a 2004 article in Nature, describing fieldwork and radiocarbon dating across a wider area,[24] revealed Norte Chico's full significance and led to widespread interest. (see more...)

26 The Olmec colossal heads are at least seventeen monumental stone representations of human heads sculpted from large basalt boulders. The heads date from at least before 900 BC and are a distinctive feature of the Olmec civilization of ancient Mesoamerica.[25] All portray mature men with fleshy cheeks, flat noses, and slightly crossed eyes; their physical characteristics correspond to a type that is still common among the inhabitants of Tabasco and Veracruz. The backs of the monuments often are flat. The boulders were brought from the Sierra de los Tuxtlas mountains of Veracruz. Given that the extremely large slabs of stone used in their production were transported over large distances, requiring a great deal of human effort and resources, it is thought that the monuments represent portraits of powerful individual Olmec rulers. Each of the known examples has a distinctive headdress. The heads were variously arranged in lines or groups at major Olmec centres, but the method and logistics used to transport the stone to these sites remain unclear.

The discovery of a colossal head at Tres Zapotes in the nineteenth century spurred the first archaeological investigations of Olmec culture by Matthew Stirling in 1938. Seventeen confirmed examples are known from four sites within the Olmec heartland on the Gulf Coast of Mexico. Most colossal heads were sculpted from spherical boulders but two from San Lorenzo Tenochtitlán were re-carved from massive stone thrones. An additional monument, at Takalik Abaj in Guatemala, is a throne that may have been carved from a colossal head. This is the only known example from outside the Olmec heartland.

Dating the monuments remains difficult because of the movement of many from their original contexts prior to archaeological investigation. Most have been dated to the Early Preclassic period (1500–1000 BC) with some to the Middle Preclassic (1000–400 BC) period. The smallest weigh 6 tons, while the largest is variously estimated to weigh 40 to 50 tons, although it was abandoned and left unfinished close to the source of its stone. (see more...)

27

Quiriguá (Spanish pronunciation: [kiɾiˈɣwa]) is an ancient Maya archaeological site in the department of Izabal in south-eastern Guatemala. It is a medium-sized site covering approximately 3 square kilometres (1.2 sq mi) along the lower Motagua River, with the ceremonial center about 1 km (0.6 mi) from the north bank. During the Maya Classic Period (AD 200–900), Quiriguá was situated at the juncture of several important trade routes. The site was occupied by 200, construction on the acropolis had begun by about 550, and an explosion of grander construction started in the 8th century. All construction had halted by about 850, except for a brief period of reoccupation in the Early Postclassic (c. 900 – c. 1200). Quiriguá shares its architectural and sculptural styles with the nearby Classic Period city of Copán, with whose history it is closely entwined.

Quiriguá's rapid expansion in the 8th century was tied to king K'ak' Tiliw Chan Yopaat's military victory over Copán in 738. When the greatest king of Copán, Uaxaclajuun Ub'aah K'awiil or "18-Rabbit", was defeated, he was captured and then sacrificed in the Great Plaza at Quiriguá. Before this, Quiriguá had been a vassal state of Copán, but it maintained its independence afterwards. The ceremonial architecture at Quiriguá is quite modest, but the site's importance lies in its wealth of sculpture, including the tallest stone monumental sculpture ever erected in the New World.

(see more...)

28

Tak'alik Ab'aj (/tɑːkəˈliːk əˈbɑː/; Mayan pronunciation: [takʼaˈlik aˈɓaχ] (listen); Spanish: [takaˈlik aˈβax]) is a pre-Columbian archaeological site in Guatemala. It was formerly known as Abaj Takalik; its ancient name may have been Kooja. It is one of several Mesoamerican sites with both Olmec and Maya features. The site flourished in the Preclassic and Classic periods, from the 9th century BC through to at least the 10th century AD, and was an important centre of commerce,[26] trading with Kaminaljuyu and Chocolá. Investigations have revealed that it is one of the largest sites with sculptured monuments on the Pacific coastal plain.[27] Olmec-style sculptures include a possible colossal head, petroglyphs and others.[28] The site has one of the greatest concentrations of Olmec-style sculpture outside of the Gulf of Mexico.[28]

Takalik Abaj is representative of the first blossoming of Maya culture that had occurred by about 400 BC.[29] The site includes a Maya royal tomb and examples of Maya hieroglyphic inscriptions that are among the earliest from the Maya region. Excavation is continuing at the site; the monumental architecture and persistent tradition of sculpture in a variety of styles suggest the site was of some importance.[30]

Finds from the site indicate contact with the distant metropolis of Teotihuacan in the Valley of Mexico and imply that Takalik Abaj was conquered by it or its allies.[31] Takalik Abaj was linked to long-distance Maya trade routes that shifted over time but allowed the city to participate in a trade network that included the Guatemalan highlands and the Pacific coastal plain from Mexico to El Salvador.

Takalik Abaj was a sizeable city with the principal architecture clustered into four main groups spread across nine terraces. While some of these were natural features, others were artificial constructions requiring an enormous investment in labour and materials.[32] The site featured a sophisticated water drainage system and a wealth of sculptured monuments. (see more...)

29

Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex is commonly abbreviated to T. rex. It lived throughout what is now western North America. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous Period, 67 to 66 million years ago. It was among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.

Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hindlimbs, Tyrannosaurus forelimbs were short and bore two clawed digits. Although other theropods rivaled or exceeded Tyrannosaurus rex in size it is one of the largest known land predators in history. The most complete specimen measures up to 12.3 m (40 ft) in length, up to 4 metres (13 ft) tall at the hips, and up to 6.8 metric tons (7.5 short tons) in weight. Tyrannosaurus rex would have been an apex predator, preying upon hadrosaurs, ceratopsians, and possibly sauropods.

More than 50 specimens of Tyrannosaurus rex have been identified, some of which are nearly complete skeletons. Soft tissue and proteins have been reported in at least one of these specimens. The abundance of fossil material has allowed significant research into many aspects of its biology. Its taxonomy is also controversial: some scientists consider Tarbosaurus bataar from Asia to be a second species of Tyrannosaurus and others maintaining Tarbosaurus as a separate genus. (see more...)

30 ?Oryzomys pliocaenicus is a fossil rodent from the Hemphillian (late Miocene) of Kansas, central United States. It is known from a single mandible (lower jaw) with the back part missing. All three molars are present, but very worn. Together, the molars are 3.6 mm long. The fossil was discovered in 1935 and described in 1939 as a possible species of Oryzomys (in open nomenclature). Later authors doubted this allocation and suggested that it may instead belong in Bensonomys or Jacobsomys, but the material may not allow a definite identification.(see more...)

31

Aetosaurs (order name Aetosauria) are an extinct order of heavily armoured, medium- to large-sized Late Triassic herbivorous archosaurs. They have small heads, upturned snouts, erect limbs, and a body covered by plate-like scutes. All aetosaurs belong to the family Stagonolepididae. Two distinct subdivisions of aeotosaurs are currently recognized, Desmatosuchinae and Aetosaurinae, based primarily on differences in the morphology of the bony scutes of the two groups. Over 20 genera of aetosaurs have been described.

Aetosaur fossil remains are known from Europe, North and South America, parts of Africa and India. Since their armoured plates are often preserved and are abundant in certain localities, aetosaurs serve as important Late Triassic tetrapod index fossils. Many aetosaurs had wide geographic ranges, but their stratigraphic ranges were relatively short. Therefore, the presence of particular aetosaurs can accurately date a site that they are found in.

Aetosaur remains have been found since the early 19th century, although the very first remains that were described were mistaken for fish scales. Aetosaurs were later recognized as crocodile relatives, with early paleontologists considering them to be semiaquatic scavengers. They are now considered to have been entirely terrestrial animals. Some forms have characteristics that may have been adaptations to digging for food. There is also evidence that some if not all aetosaurs made nests. (see more...)

32

Chitinozoa (singular: chitinozoan, plural: chitinozoans) are a taxon of flask-shaped, organic walled marine microfossils produced by an as yet unknown animal. Common from the Ordovician to Devonian periods (i.e. the mid-Paleozoic), the millimetre-scale organisms are abundant in almost all types of marine sediment across the globe. This wide distribution, and their rapid pace of evolution, makes them valuable biostratigraphic markers.

Their bizarre form has made classification and ecological reconstruction difficult. Since their discovery in 1931, suggestions of protist, plant, and fungalaffinities have all been entertained. The organisms have been better understood as improvements in microscopy facilitated the study of their fine structure, and there is mounting evidence to suggest that they represent either the eggs or juvenile stage of a marine animal.

The ecology of chitinozoa is also open to speculation; some may have floated in the water column, where others may have attached themselves to other organisms. Most species were particular about their living conditions, and tend to be most common in specific paleoenvironments. Their abundance also varied with the seasons.(see more...)

33

The Cloudinids, an early metazoan family containing the genus Cloudina, lived in the late Ediacaran period and became extinct at the base of the Cambrian. They formed millimetre-scale conical fossils consisting of calcareous cones nested within one another; the appearance of the organism itself remains unknown. Current scientific opinion is divided between classifying them as polychaetes and regarding it as unsafe to classify them as members of any broader grouping.

Cloudinids had a wide geographic range, reflected in the present distribution of localities in which their fossils are found, and are an abundant component of some deposits. They never appear in the same layers as soft-bodied Ediacaran biota, but the fact that some sequences contain Cloudinids and Ediacaran biota in alternating layers suggests that these groups had different environmental preferences.

Cloudinids are important in the history of animal evolution for two reasons. They are among the earliest and most abundant of the small shelly fossils with mineralized skeletons, and therefore feature in the debate about why such skeletons first appeared in the Late Ediacaran. The most widely-supported answer is that their shells are a defense against predators, as some Cloudina specimens from China bear the marks of multiple attacks, which suggests they survived at least a few of them. The evolutionary arms race which this indicates is commonly cited as a cause of the Cambrian explosion of animal diversity and complexity. (see more...)

34

Coal balls, despite their name, are calcium-rich masses of permineralised life forms, generally having a round shape. Coal balls were formed roughly 300 million years ago, during the Carboniferous Period. They are exceptional at preserving organic matter, which makes them useful to scientists, who cut and peel the coal balls to research the geological past of the Earth.

In 1855, two English scientists, Joseph Dalton Hooker and Edward William Binney, discovered coal balls in England, and the initial research on coal balls was carried out in Europe. It was not until 1922 that coal balls were discovered and identified in North America. Since then, coal balls have been discovered in other countries and they have led to the discovery of over 300 species and 130 genera.

Coal balls can be found in coal seams across North America and Eurasia. North American coal balls are relatively widespread, both stratigraphically and geologically, as compared to coal balls from Europe. The oldest known coal balls were found in Germany and the former Czechoslovakia.

35

Dimetrodon is an extinct genus of synapsid that lived during the Early Permian, around 299–270 million years ago (Ma). It is a member of the family Sphenacodontidae. The most prominent feature of Dimetrodon is the large sail on its back formed by elongated spines extending from the vertebrae. It walked on four legs and had a tall, curved skull with large teeth of different sizes set along the jaws. Generally reptile-like in appearance and physiology, Dimetrodon is nevertheless more closely related to mammals than it is to any living reptilian group, though it is not a direct ancestor of any mammals. Most fossils have been found in the southwestern United States, the majority coming from a geological deposit called the Red Beds in Texas and Oklahoma. More recently, fossils have been found in Germany. Over a dozen species have been named since the genus was firstdescribed in 1878. Dimetrodon was probably one of the top predators in Early Permian ecosystems, feeding on fish and tetrapods, including reptiles as well as amphibians. Smaller Dimetrodon species may have had different ecological roles. The sail of Dimetrodon may have been used to stabilize its spine or to heat and cool its body as a form of thermoregulation. Some recent studies argue that the sail would have been ineffective at removing heat from the body, and was more likely used in sexual display. (see more...)

36

The Kirtlandian is a North American land-vertebrate faunal age of the Cretaceous period, following the Judithian and succeeded by the Edmontonian. It lasted about 2 million years, ca 74.8 to 72.8 Mya and is characterized by the ceratopsian Pentaceratops sternbergii, which lived throughout the Kirtlandian. It was first named by R.M. Sullivan and S.G. Lucas in 2003 as a faunal age for the Kirtland and Fruitland formations. Previously, only five land-vertebrate ages were identified from the Late Cretaceous. as identified by Loris S. Russell in 1975, they include the Paluxian, Aquilan, Judithian, Edmontonian, and the Lancian. Before the naming of the Kirtlandian, three gaps, between the Paluxian and Aquilan, the Aquilan and the Judithian, and the Judithian and Edmontonian, were identified but not named. The Fruitland Formation measures 97 to 107 metres (318 to 351 ft) thick, and with the 594 metres (1,949 ft) of the Kirtland Formation, the Kirtlandian consists of 701 metres (2,300 ft) of sediments. The rock types within the formations are primarily coal beds, but also include sandstone, siltstone, mudstone, and shale. Within the sediments with a Kirtlandian age, two local faunas, the Hunter Wash local fauna, and the Willow Wash local fauna, have been identified. The currently accepted date of the Kirtlandian is 74.8 to 72.8 million years ago. (see more...)

37

Macabeemyrma is an extinct genus of bulldog ants in the subfamily Myrmeciinae containing the single species Macabeemyrma ovata, described in 2006 from Ypresian stage (Early Eocene) deposits of British Columbia, Canada. Only a single specimen is known; a holotype queen found preserved as a compression fossil. The specimen had no wings and small portions of its legs and eyes were faintly preserved. It was a large ant, reaching 25 millimetres (0.98 in) in length. This ants' behaviour would have been similar to that of extant Myrmeciinae ants, such as foraging singly in search for arthropod prey and nesting in soil or in trees. Macabeemyrma shows similarities to extinct ants in the genus Ypresiomyrma, and to the living Nothomyrmecia macrops, but has not been conclusively assigned to any tribe, instead generally regarded as incertae sedis within Myrmeciinae. However, the sole specimen lacks definitive traits, and its classification in Myrmeciinae, and even its identity as an ant, has been challenged. (see more...)

38

Megalodon (/ˈmɛɡələdɒn/ MEG-ə-lə-don; meaning "big tooth", from Ancient Greek: μέγας, translit. (megas), lit. 'big, mighty' and ὀδoύς (odoús), "tooth"—whose stem is odont-, as seen in the genitive case form ὀδόντος, odóntos) is an extinct species of shark that lived approximately 15.9 to 2.6 million years ago, during the Cenozoic Era (middle Miocene to end of Pliocene).

The taxonomic assignment of C. megalodon has been debated for nearly a century, and is still under dispute. The two major interpretations are Carcharodon megalodon (under family Lamnidae) or Carcharocles megalodon (under the family Otodontidae). Consequently, the scientific name of this species is commonly abbreviated C. megalodon in the literature.

C. megalodon is regarded as one of the largest and most powerful predators in vertebrate history, and likely had a profound impact on the structure of marine communities. Fossil remains suggest that this giant shark reached a maximum length of 18 metres (59 ft), and also affirm that it had a cosmopolitan distribution. Scientists suggest that C. megalodon looked like a stockier version of the great white shark, Carcharodon carcharias. (see more...)

39

Opabinia is an extinct stem-arthropod genus found in Cambrian fossil deposits. The only known species, O. regalis, is known from the Middle Cambrian Burgess Shale Lagerstätte of British Columbia, Canada. Fewer than twenty good specimens have been described. Opabinia was a soft-bodied animal of modest size, and its segmented body had lobes along the sides and a fan-shaped tail. The head shows unusual features: five eyes, a mouth under the head and facing backwards, and a proboscis that probably passed food to the mouth. Opabinia probably lived on the seafloor, using the proboscis to seek out small, soft food. When the first thorough examination of Opabinia in 1975 revealed its unusual features, it was thought to be unrelated to any known phylum, although possibly related to a hypothetical ancestor of arthropods and of annelid worms. However other finds, most notably Anomalocaris, suggested that it belonged to a group of animals that were closely related to the ancestors of arthropods and of which the living animals onychophorans and tardigrades may also be members.(see more...)

40

Ornatifilum (Latin ornatis + filum, Ornamented filament) is an artificial form genus, which is used to categorise any small, branched filaments with external ornamentation. It has been applied to microfossils of Devonian age with possible fungal affinities; two "species" have been described, and further Silurian fossils closely resemble it. These Silurian specimens hint that the organisms may have been fungal, placing them among the oldest representatives of this kingdom. (see more...)

41

Othnielosaurus is a genus of ornithischian dinosaur that lived about 155 to 148 million years ago, during the Late Jurassic-age Morrison Formation of the western United States. It is named in honor of famed paleontologist Othniel Charles Marsh, and was formerly assigned to the genus Laosaurus. This genus was coined to hold fossils formerly included in Othnielia, which is based on remains that may be too sparse to hold a name; as such, it is part of decades of research to untangle the taxonomy left behind by Marsh and his rival Edward Drinker Cope from the Bone Wars. Othnielosaurus has usually been classified as a hypsilophodont, a type of generalized small bipedal herbivore or omnivore, although recent research has called this and the existence of a distinct group of hypsilophodonts into question. (see more...)

42

Protomycena is an extinct monotypic genus of gilled fungus in the Mycenaceae family, of order Agaricales. At present it contains the single species Protomycena electra, known from a single specimen collected in an amber mine in the Cordillera Septentrional area of the Dominican Republic. The fruit body of the fungus has a convex cap that is 5 mm (0.2 in) in diameter, with distantly spaced gills on the underside. The curved stipe is smooth and cylindrical, measuring 0.75 mm (0.030 in) thick by 10 mm (0.39 in) long, and lacks a ring. It resembles extant (currently living) species of the genus Mycena. Protomycena is one of only five known agaric fungus species known in the fossil record and the second to be described from Dominican amber. (see more...)

43

Pteranodon (/tɪˈrænədɒn/; from Greek πτερόν ("wing") and ἀνόδων ("toothless")) is a genus of pterosaurs which included some of the largest known flying reptiles, with wingspans over 6 metres (20 ft). It existed during the late Cretaceous geological period of North America in present day Kansas, Alabama, Nebraska, Wyoming, and South Dakota. More fossil specimens of Pteranodon have been found than any other pterosaur, with about 1,200 specimens known to science, many of them well preserved with nearly complete skulls and articulated skeletons. It was an important part of the animal community in the Western Interior Seaway. Pteranodon was not a dinosaur. By definition, all dinosaurs belong to the groups Saurischia and Ornithischia, which exclude pterosaurs. Nevertheless, Pteranodon is frequently featured in dinosaur books and is strongly associated with dinosaurs by the general public. (see more...)

44

Pterosaurs were flying reptiles of the clade or order Pterosauria. They existed from the late Triassic to the end of the Cretaceous Period (228 to 66 million years ago). Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings were formed by a membrane of skin, muscle, and other tissues stretching from the ankles to a dramatically lengthened fourth finger. Early species had long, fully toothed jaws and long tails, while later forms had a highly reduced tail, and some lacked teeth. Many sported furry coats made up of hair-like filaments known as pycnofibres, which covered their bodies and parts of their wings. Pterosaurs spanned a wide range of adult sizes, from the very small Nemicolopterus to the largest known flying creatures of all time, including Quetzalcoatlus and Hatzegopteryx. Pterosaurs are often referred to in the popular media and by the general public as flying dinosaurs, but this is incorrect. However, like the dinosaurs, pterosaurs are more closely related to birds than to any living reptile. Pterosaurs are also incorrectly referred to as pterodactyls, particularly by journalists. "Pterodactyl" refers specifically to members of the genus Pterodactylus, and more broadly to members of the suborder Pterodactyloidea of the pterosaurs. (see more...)

45

The Saint Croix macaw (Ara autocthones) is an extinct species of parrot. The last populations lived on the Caribbean islands Saint Croix and Puerto Rico. It was originally described by Alexander Wetmore in 1937 based on a subfossil limb bone unearthed by L. J. Korn in 1934 from a kitchen midden at an Amerindian archeological site on Saint Croix. A second specimen was described by Storrs L. Olson and Edgar J. Máiz López based on various limb and shoulder bones excavated from a similar site on Puerto Rico, while a possible third specimen from Montserrat has been reported. The species is one of two medium-sized macaws of the Caribbean, the other being the smaller Cuban red macaw (Ara tricolor). Its bones are distinct from Amazon parrots as well as from the other medium-sized but geographically distant Lear's macaw (Anodorhynchus leari) and blue-throated macaw (Ara glaucogularis). The natural range is unknown because parrots were regularly traded between islands by indigenous people. Like other parrot species in the Caribbean, the extinction of the Saint Croix macaw is believed to be linked to the arrival of humans in the region. (see more...)

46

The small shelly fauna or small shelly fossils, abbreviated to SSF, are mineralized fossils, many only a few millimetres long, with a nearly continuous record from the latest stages of the Ediacaran to the end of the Early Cambrian period. They are very diverse, and there is no formal definition of "small shelly fauna" or "small shelly fossils". Almost all are from earlier rocks than more familiar fossils such as trilobites. Since most SSFs were preserved by being covered quickly with phosphate and this method of preservation is mainly limited to the Late Ediacaran and Early Cambrian periods, the animals that made them may actually have arisen earlier and persisted after this time span. The bulk of the fossils are fragments or disarticulated remains of larger organisms, including sponges, molluscs, slug-like halkieriids, brachiopods, echinoderms, and onychophoran-like organisms that may have been close to the ancestors of arthropods. Although the small size and often fragmentary nature of SSFs makes it difficult to identify and classify them, they provide very important evidence for how the main groups of marine invertebrates evolved, and particularly for the pace and pattern of evolution in the Cambrian explosion. Besides including the earliest known representatives of some modern phyla, they have the great advantage of presenting a nearly continuous record of Early Cambrian organisms whose bodies include hard parts. (see more...)

47

Smilodon /ˈsmaɪlədɒn/, is an extinct genus of machairodont felid. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats. Smilodon lived in the Americas during the Pleistocene epoch (2.5 mya–10,000 years ago). The genus was named in 1842, based on fossils from Brazil. Three species are recognized today: S. gracilis, S. fatalis and S. populator.

Overall, Smilodon was more robustly built than any extant (living) cat, with particularly well-developed forelimbs and exceptionally long upper canines. Its jaw had a bigger gape than that of modern cats and its upper canines were slender and fragile, being adapted for precision killing. S. gracilis was the smallest species at 55 to 100 kg (120 to 220 lb) in weight. S. populator from South America is perhaps the largest known felid at 220 to 400 kg (490 to 880 lb) in weight and 120 cm (47 in) in height.

Smilodon probably lived in closed habitats such as forests and bush, which would have provided cover for ambushing prey. Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species, but the exact cause is unknown. (see more...)

48

The Temnospondyli are a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian, and Triassic periods. A few species continued into the Cretaceous. Fossils have been found on every continent. During about 210 million years of evolutionary history, they adapted to a wide range of habitats, including fresh water, terrestrial, and even coastal marine environments. Their life history is well understood, with fossils known from the larval stage, metamorphosis, and maturity. Most temnospondyls were semiaquatic, although some were almost fully terrestrial, returning to the water only to breed. These temnospondyls were some of the first vertebrates fully adapted to life on land. Although temnospondyls are considered amphibians, many had characteristics, such as scales, claws, and armor-like bony plates, that distinguish them from modern amphibians. Authorities disagree over whether temnospondyls were ancestral to modern amphibians (frogs, salamanders, and caecilians), or whether the whole group died out without leaving any descendants. Different hypotheses have placed modern amphibians as the descendants of temnospondyls, another group of early tetrapods called lepospondyls, or even as descendants of both groups (with caecilians evolving from lepospondyls and frogs and salamanders evolving from temnospondyls). Recent studies place a family of temnosondyls called the amphibamids as the closest relatives of modern amphibians. Similarities in teeth, skulls, and hearing structures link the two groups. (see more...)

Selected articles covering the Prehistory of North America and human science, culture, and economics
1

Bone Sharps, Cowboys, and Thunder Lizards: A Tale of Edward Drinker Cope, Othniel Charles Marsh, and the Gilded Age of Paleontology (2005) is a graphic novel written by Jim Ottaviani and illustrated by the company Big Time Attic. The book tells a slightly fictionalized account of the Bone Wars, a period of intense excavation, speculation, and rivalry which led to a greater understanding of dinosaurs in the western United States. This novel is the first semi-fictional work written by Ottaviani; previously, he had taken no creative license with the characters he depicted, portraying them strictly according to historical sources. Bone Sharps follows the two scientists Edward Drinker Cope and Othniel Marsh as they engage in an intense rivalry for prestige. Ottaviani has Cope and Marsh interact and meet many important figures of the Gilded Age, from P. T. Barnum to U.S. Grant, as the two scientists pursue their hotheaded and sometimes illegal acquisitions of fossils. Unlike in his previous books, "the scientists are the bad guys this time". Upon release, the novel received praise from critics for its exceptional historical content, although some reviewers wished more fiction had been woven into the story. (see more...)

2

The Bone Wars is the name given to a period of intense fossil speculation and discovery during the Gilded Age of American history, marked by a heated rivalry between Edward Drinker Cope and Othniel Charles Marsh. The two paleontologists used underhanded methods to out-compete the other in the field, resorting to bribery, theft, and destruction of bones. The scientists also attacked each other in scientific publications, attempting to ruin the other's credibility and cut off his funding.

Originally colleagues who were civil to each other, Cope and Marsh became bitter enemies after several personal slights between them. Their pursuit of bones led them west to rich bone beds in Colorado, Nebraska, and Wyoming. From 1877 to 1892, both paleontologists used their wealth and influence to finance their own expeditions and to procure services and fossils from dinosaur hunters. By the end of the Bone Wars, both men exhausted their funds in fueling their intense rivalry.

Cope and Marsh were financially and socially ruined by their efforts to disgrace each other, but their contributions to science and the field of paleontology were massive; the scientists left behind tons of unopened boxes of fossils on their deaths. The feud between the two men led to over 142 new species of dinosaurs being discovered and described. Several historical books and fictional adaptations have also been published about this period of intense paleontological activity. (see more...)

3

Edward Drinker Cope (July 28, 1840 – April 12, 1897) was an American paleontologist and comparative anatomist, as well as a noted herpetologist and ichthyologist. Cope distinguished himself as a child prodigy, publishing his first scientific paper at the age of nineteen. Cope later married and moved from Philadelphia to Haddonfield, New Jersey, although Cope would maintain a residence and museum in Philadelphia in his later years.

Cope had little formal scientific training, and he eschewed a teaching position for field work. He made regular trips to the American West prospecting in the 1870s and 1880s, often as a member of United States Geological Survey teams. A personal feud between Cope and paleontologist Othniel Charles Marsh led to a period of intense fossil-finding competition now known as the Bone Wars. Cope's financial fortunes soured after failed mining ventures in the 1880s. He experienced a resurgence in his career toward the end of his life before dying in 1897.

Cope's scientific pursuits nearly bankrupted him, but his contributions helped to define the field of American paleontology. He was a prodigious writer, with 1,400 papers published over his lifetime, although his rivals would debate the accuracy of his rapidly published works. He discovered, described, and named more than 1,000 vertebrate species including hundreds of fishes and dozens of dinosaurs. His proposals on the origin of mammalian molars and for the gradual enlargement of mammalian species over geologic time ("Cope's Law") are notable among his theoretical contributions. (see more...)

4

Petrified Forest National Park is a United States national park in Navajo and Apache counties in northeastern Arizona. Named for its large deposits of petrified wood, the park covers about 146 square miles (380 km2), encompassing semi-desert shrub steppe as well as highly eroded and colorful badlands. The site, the northern part of which extends into the Painted Desert, was declared a national monument in 1906 and a national park in 1962. The Petrified Forest is known for its fossils, especially fallen trees that lived in the Late Triassic, about 225 million years ago. The sediments containing the fossil logs are part of the widespread and colorful Chinle Formation, from which the Painted Desert gets its name. Beginning about 60 million years ago, the Colorado Plateau, of which the park is part, was pushed upward by tectonic forces and exposed to increased erosion. All of the park's rock layers above the Chinle, except geologically recent ones found in parts of the park, have been removed by wind and water. In addition to petrified logs, fossils found in the park have included Late Triassic ferns, cycads, ginkgoes, and many other plants as well as fauna including giant reptiles called phytosaurs, large amphibians, and early dinosaurs. Paleontologists have been unearthing and studying the park's fossils since the early 20th century. (see more...)

5

Chaco Culture National Historical Park is a United States National Historical Park hosting the densest and most exceptional concentration of pueblos in the American Southwest. The park is located in northwestern New Mexico, between Albuquerque and Farmington, in a remote canyon cut by the Chaco Wash. Containing the most sweeping collection of ancient ruins north of Mexico, the park preserves one of the United States' most important pre-Columbian cultural and historical areas.

Between AD 900 and 1150, Chaco Canyon was a major center of culture for the Ancient Pueblo Peoples. Chacoans quarried sandstone blocks and hauled timber from great distances, assembling fifteen major complexes that remained the largest buildings in North America until the 19th century. Evidence of archaeoastronomy at Chaco has been proposed, with the "Sun Dagger" petroglyph at Fajada Butte a popular example. Many Chacoan buildings may have been aligned to capture the solar and lunar cycles, requiring generations of astronomical observations and centuries of skillfully coordinated construction. Climate change is thought to have led to the emigration of Chacoans and the eventual abandonment of the canyon, beginning with a fifty-year drought commencing in 1130.

Composing a UNESCO World Heritage Site located in the arid and sparsely populated Four Corners region, the Chacoan cultural sites are fragile; concerns of erosion caused by tourists have led to the closure of Fajada Butte to the public. The sites are considered sacred ancestral homelands by the Hopi and Pueblo people, who maintain oral accounts of their historical migration from Chaco and their spiritual relationship to the land. Though park preservation efforts can conflict with native religious beliefs, tribal representatives work closely with the National Park Service to share their knowledge and respect the heritage of the Chacoan culture.

It is on the Trails of the Ancients Byway, one of the designated New Mexico Scenic Byways. (see more...)

6

Sylvanus Griswold Morley (June 7, 1883 – September 2, 1948) was an American archaeologist, epigrapher, and Mayanist scholar who made significant contributions toward the study of the pre-Columbian Maya civilization in the early 20th century.

Morley made extensive excavations of the Maya site of Chichen Itza that he directed on behalf of the Carnegie Institution. He also published several large compilations and treatises on Maya hieroglyphic writing, and wrote popular accounts on the Maya for a general audience.

To his contemporaries, "Vay" Morley was one of the leading Mesoamerican archaeologists of his day. Although more recent developments in the field have resulted in a re-evaluation of his theories and works, his publications, particularly on calendric inscriptions, are still cited. In his role as director of various projects sponsored by the Carnegie Institution, he oversaw and encouraged many others who later established notable careers in their own right. His commitment and enthusiasm for Maya studies helped inspire the necessary sponsorship for projects that would ultimately reveal much about ancient Maya civilization.

Morley also conducted espionage in Mexico on behalf of the United States during World War I, but the scope of those activities only came to light well after his death. His archaeological field work in Mexico and Central America provided suitable cover for investigating German activities and anti-American activity at the behest of the United States' Office of Naval Intelligence. (see more...)

7

The history of paleontology traces the history of the effort to study the fossil record left behind by ancient life forms. Although fossils had been studied by scholars since ancient times, the nature of fossils and their relationship to life in the past became better understood during the 17th and 18th centuries. At the end of the 18th century the work of Georges Cuvier ended a long running debate about the reality of extinction and led to the emergence of paleontology as a scientific discipline.

The first half of the 19th century saw paleontological activity become increasingly well organized. This contributed to a rapid increase in knowledge about the history of life on Earth, and progress towards definition of the geologic time scale. As knowledge of life's history continued to improve, it became increasingly obvious that there had been some kind of successive order to the development of life. After Charles Darwin published Origin of Species in 1859, much of the focus of paleontology shifted to understanding evolutionary paths.

The last half of the 19th century saw a tremendous expansion in paleontological activity, especially in North America. The trend continued in the 20th century with additional regions of the Earth being opened to systematic fossil collection, as demonstrated by a series of important discoveries in China near the end of the 20th century. There was also a renewed interest in the Cambrian explosion that saw the development of the body plans of most animal phyla. (see more...)

8 Stephen Jay Gould (September 10, 1941 – May 20, 2002) was an American paleontologist, evolutionary biologist, and historian of science. He was also one of the most influential and widely read writers of popular science of his generation. Gould spent most of his career teaching at Harvard University and working at the American Museum of Natural History in New York. In the later years of his life, Gould also taught biology and evolution at New York University.

Gould's most significant contribution to evolutionary biology was the theory of punctuated equilibrium, which he developed with Niles Eldredge in 1972. The theory proposes that most evolution is marked by long periods of evolutionary stability, which is punctuated by rare instances of branching evolution. The theory was contrasted against phyletic gradualism, the popular idea that evolutionary change is marked by a pattern of smooth and continuous change in the fossil record.

Most of Gould's research was based on the land snail genera Poecilozonites and Cerion. He also contributed to evolutionary developmental biology, and has received wide praise for his book Ontogeny and Phylogeny. In evolutionary theory he opposed strict selectionism, sociobiology as applied to humans, and evolutionary psychology. Gould was known by the general public mainly from his 300 popular essays in the magazine Natural History, and his books written for a non-specialist audience.

In April 2000, the US Library of Congress named him a "Living Legend". (see more...)

9

Raptor Red is a 1995 American novel by paleontologist Robert T. Bakker. The book is a third-person account of dinosaurs during the Cretaceous Period, told from the point of view of Raptor Red, a female Utahraptor. Raptor Red features many of Bakker's theories regarding dinosaurs' social habits, intelligence, and the world in which they lived.

The book follows a year in Raptor Red's life as she loses her mate, finds her family, and struggles to survive in a hostile environment. Bakker drew inspiration from Ernest Thompson Seton's works that look at life through the eyes of predators, and said that he found it "fun" to write from a top predator's perspective. Bakker based his portrayals of dinosaurs and other prehistoric wildlife on fossil evidence, as well as studies of modern animals.

When released, Raptor Red was generally praised: Bakker's anthropomorphism was seen as a unique and positive aspect of the book, and his writing was described as folksy and heartfelt. Criticisms of the novel included a perceived lack of characterization and average writing. Some scientists, such as paleontologist David B. Norman, took issue with the scientific theories portrayed in the novel, fearing that the public would accept them as fact, while Discovery Channel host Jay Ingram defended Bakker's creative decisions in an editorial.

(see more...)

DYK

 * ...that the first Styxosaurus fossil to be discovered had about 250 stones in its stomach that it probably swallowed for ballast?
 * ... that the extinct winter-hazel species Corylopsis readae was described from a single Ypresian fossil?
 * ... that the extinct fir species Abies milleri, known from Early Eocene fossils (pictured) found in Ferry County, Washington, is considered the oldest confirmed record for the fir genus?
 * ... that fossils of the temnospondyl  amphibian   Kourerpeton   were notoriously discovered in the window of a barber's shop in Arizona?
 * ... that the Klondike Mountain Formation has fossil hot springs and is a lagerstätten?
 * ... that the extinct ant Anochetus ambiguus has a spiny petiole?
 * ... that the extinct bivalve subfamily Praenuculinae can be told apart from its sister subfamily by looking at teeth?
 * ... that the extinct trilobite Bumastus (artist's rendition pictured) was named after its resemblance to large grapes?
 * ... that despite its name, there is speculation that Temple VI at the Maya city of Tikal was not a temple?
 * ... that the distinct fauna of the Kirtlandian includes the dinosaur Pentaceratops sternbergii?
 * ... that a fossil of the extinct monitor lizard Saniwa preserves cartilage, scales, and even a wind pipe?
 * ... that Adolf Carl Noé challenged disbelief in the possibility of North American coal balls (example pictured) by presenting a wheelbarrow full of them?
 * ... that the extinct stingray Heliobatis (pictured) has been found with up to three stings on its tail?
 * ... that Leurospondylus ultimus was so named as it was originally thought to be the last occurrence of a plesiosaur?
 * ... that Cliff Palace (pictured) is the largest cliff dwelling at Mesa Verde National Park, a World Heritage Site in Colorado?
 * ... that Cottonwood Limestone from Kansas was used to build landmarks like the Kansas State Capitol, Great Overland Station, and Bill Snyder Family Football Stadium (pictured)?
 * ...that the exposed bedrock of the Duluth Complex was formed from magma emitted when the North American plate began to split apart in the Midcontinent Rift?
 * ... that the collection of the Arizona Mining and Mineral Museum includes a specimen of native copper that is 8 ft (2.4 m) long?
 * ... that the extinct wasps Dryinus grimaldii and Dryinus rasnitsyni are distinguishable by the modified claws on their front legs?
 * ... that the Miocene maple Acer latahense is most similar in appearance to the living Honshū maple?


 * ... that the Hilda mega-bonebed is Canada's largest dinosaur bonebed, preserving thousands of the horned dinosaur Centrosaurus apertus across an area of 2.3 square kilometers?
 * ... that Cullerlie stone circle (pictured) in Aberdeenshire has a unique layout, with eight stones surrounding eight small cairns?
 * ... that wings of the extinct moth lacewing Allorapisma are most similar to a Cretaceous genus from Brazil?
 * ... that some of the artifacts at Pocahontas Mounds, an archaeological site from the Plaquemine Mississippian culture in Hinds County, Mississippi, were recovered by schoolchildren?
 * ... that the cat gap is a period in the fossil record (cat illustration pictured) of approximately 25 to 17 million years ago in which there were few cats or cat-like species?
 * ... that Augustasaurus' name comes from the mountain range of northwestern Nevada, where its fossilized bones were first discovered?
 * ... that seeds of the extinct Paleocene pine Pinus peregrinus are most similar to those of the modern red pine and tropical pine?
 * ... that the Devonian stem tetrapod Tinirau clackae, transitional between fish and land vertebrates, was named after the half-human half-fish character Tinirau in Polynesian legend?
 * ... that the nearest living relatives of Eosacantha, a fossil tortoise beetle from Colorado, are found in Africa, tropical Asia, and Australia?
 * ... that geologist Adolph Knopf frequently collaborated with his wife Eleanora Knopf, but when he worked at Yale University she had to work out of his office because Yale would not hire women?
 * ... that within the United States, dinosaur fossils (example pictured) have been found in Alabama, Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Georgia, Idaho, Iowa, Kansas, Louisiana, Maryland, Massachusetts, Minnesota, Mississippi, Missouri, Montana, Nebraska, Nevada, New Jersey, New Mexico, New York, North Carolina, North Dakota, Oklahoma, Oregon, Pennsylvania, South Carolina, South Dakota, Tennessee, Texas, Utah, Virginia, Washington, D.C., and Wyoming, but not in Florida, Hawaii, Illinois, Indiana, Kentucky, Maine, Michigan, New Hampshire, Ohio, Rhode Island, Vermont, Washington, West Virginia, or Wisconsin?
 * ... that Mississippian stone statuary (examples pictured), made by members of the Mississippian culture (800 to 1600 CE), are artifacts of polished stone in the shape of human figurines?
 * ... that oviraptorosaurs were thought to be egg-eaters after the discovery of Oviraptor on a nest of presumed Protoceratops eggs, until the nest was recognized as belonging to Oviraptor itself?
 * ...that the Norte Chico civilization is the oldest known civilization in the Americas?
 * ... that the extinct mason bee species Anthidium exhumatum and Anthidium scudderi are known from the Eocene Florissant Formation in Colorado?
 * ... that paleontologist Gerta Keller theorizes that dinosaurs did not become extinct until 300,000 years after the Chicxulub meteor, though she agrees that "I'm sure the day after, they had a headache"?
 * ...that the enigmatic Ediacaran biota (fossil pictured) have been classified into every major group of lifeforms, including their own kingdom?
 * ...that the Stag-moose (Cervalces scotti) went extinct about 11,500 years ago, part of a mass extinction of large North American mammals toward the end of the most recent ice age?
 * ... that the Barnesville Petroglyph is unusual because its human faces have noses?
 * ... that the wings of the extinct ant Aphaenogaster longaeva had "excessively delicate" hairs?
 * ... that the extinct plant species Eucommia jeffersonensis and Eucommia rolandii were both described from fossils in 1997?
 * ... that the extinct maple Acer ivanofense is known from four Alaskan fossils?
 * ... that the amber entombing the extinct ant Haidoterminus cippus (pictured) was preserved in a lagoon or saltwater marsh?
 * ... that one species of the extinct wasp Palaeovespa fed caterpillars to its larvae?
 * ... that Appianoporites, Margaretbarromyces, and Quatsinoporites are all fossil fungi from Vancouver Island, British Columbia?
 * ... that the Sisquoc Formation in Southern California supports the largest diatomite mining operation in the world?
 * ... that the family placement for the fossil moth genus Dominickus was not noticed until entomologist Norman Tindale was looking at pictures of modern moths from Australia?
 * ... that the Maya site of Altar de Sacrificios in Guatemala was one of the first places to be settled in the Maya lowlands?
 * ... that the Late Eocene marine Hoko River Formation is noted for producing crab, gastropod, cephalopod, and wood fossils?
 * ... that the extinct sweat bee Halictus? savenyei was the first fossil bee from Canada to be described?
 * ... that the fossil ant Azteca eumeces is one of two Azteca species found in Dominican amber?
 * ... that species in the fossil ant genus Myrmeciites are named for Hercules, Goliath, and a river?
 * ... that the type specimen of the extinct nutmeg yew Torreya clarnensis is located in Florida?
 * ... that the Miocene maple Acer traini may be the same species as the living Douglas Maple (fruits pictured)?
 * ... that unusual archosauromorph reptile Teraterpeton from the Late Triassic of Nova Scotia had nostril openings in its skull that were longer than its eye sockets?
 * ...that geologist T.H. Clark retired from McGill University in Quebec, Canada, at the age of 100, after teaching for 69 years?
 * ... that 94% of Dartmoor kistvaens (pictured) have the longer axis of the tomb oriented NW/SE, apparently so that the deceased face the sun?
 * ...that the largest sea turtles ever to have swum the oceans belonged to the family Protostegidae?
 * ...that eighty years on, scientists are still debating whether the Palæozoic fossils known as Chitinozoans (SEM image pictured) represent plants, animals or eggs?
 * ... that in 1968 American archaeologist A. Ledyard  Smith received the Order of the Quetzal  from the Guatemalan  government for his services to the cultural heritage of the country?
 * ... that the extinct, Triassic, bivalve family Cassianellidae may have evolved from the family Bakevelliidae, which survived longer into the Eocene?
 * ... that one species of the extinct Eocene bulldog ant Ypresiomyrma reached up to 25 mm in length?
 * ... that Bruce Erickson, an American paleontologist, has a collection of about a million specimens of ancient fossils?
 * ... that the ancient Maya architectural complex of Tazumal, in El Salvador, contained some of the earliest known metal artefacts from Mesoamerica?
 * ... that the newly named extinct prawn Aciculopoda is the third unambiguous fossil decapod from before the Mesozoic?
 * ... that at the time of description, the extinct Tilia johnsoni (pictured) was the oldest basswood macrofossil occurrence?
 * ... that despite damage from a tramway, the Deffenbaugh Site is one of the most valuable archaeological sites in Fayette County, Pennsylvania?
 * ... that although no Mississippian copper plates have ever been found at Cahokia, it is the only Mississippian culture site where a copper workshop has been located by archaeologists?
 * ... that a small fetus is preserved in the holotype fossil of the extinct stingray Asterotrygon?
 * ... that James L. Swauger continued his archaeological work with petroglyphs for fifteen years after his nominal retirement?
 * ... that what is now the southwestern United States was at one time connected to East Antarctica according to the SWEAT model?
 * ... that the extinct rose species Stonebergia columbiana is named for its type locality of British Columbia?
 * ... that the Classic Period Maya archaeological site of Quiriguá in Guatemala has what is possibly the largest free-standing worked monolith (pictured) in the New World?
 * ... that paleontologists have discovered the fossilized eggs of cephalopods, fishes, and reptiles, with some dinosaur eggs (pictured) being preserved with pathological shell deformities?
 * ... that fossils of the extinct hazelnut relative Coryloides were informally identified as palm nuts first?
 * ... that the Ph.D dissertation of taphonomist Kay Behrensmeyer suggested that sauropods were terrestrial?
 * ... that the extinct sumac Rhus rooseae was described from fossils over 35 million years old?
 * ... that the extinct hazel species Corylus johnsonii (fruit pictured) resembles three modern hazels found in China?
 * ... that major discoveries in the history of ceratosaur research include horned predators like Ceratosaurus (pictured), Majungasaurus, and Carnotaurus, as well as a bonebed of the projecting-toothed Masiakasaurus?
 * ... that excavations of the Cherokee town Tallassee, burnt down during the Chickamauga Wars and submerged by an artificial lake since 1957, uncovered evidence of habitation as early as the Woodland period?
 * ... that with a forewing length of only 3.36 mm Microberotha is one of the smallest known beaded lacewings to have been described?
 * ... that the Classic Period Maya city of Motul de San José in Guatemala made tribute payments of high quality ceramics after its military defeat?
 * ... that the shortest fossil termite bug is Termitaradus avitinquilinus?
 * ... that Ohio's Indian Mound Reserve includes two prehistoric earthworks (one pictured) and a canyon where a battle was reputedly fought?
 * ... that the only male "sweat bee" to have been documented from Dominican amber is the type specimen for the extinct Eickwortapis?
 * ... that Fort Center may be the earliest archaeological site in Florida where maize was cultivated?
 * ... that Mastotermes electromexicus was the first giant northern termite described from the New World?
 * ... that the oldest association between Trypanosoma, which causes Chagas disease, and its vector, the assassin bug Triatoma, is found in Triatoma dominicana and Trypanosoma antiquus?
 * ...that J. Harlan Bretz's  theories on the origins of the Channeled Scablands started a forty year debate between neocatastrophist and uniformitarianist geologists?
 * ... that the extinct Protosialis casca is one of only two known alderflies from the West Indies?
 * ... that the extinct fern species Osmunda wehrii was named in honor of Northwest school painter and amateur paleobotanist Wesley C. Wehr?
 * ... that the fossil pelican Pelecanus schreiberi from North Carolina was possibly the largest species of pelican ever?
 * ... that the fossil ant Aphaenogaster praerelicta is entombed in amber with three flies, two springtails, and a wasp?
 * ... that the extinct sweat bee genus Oligochlora contains six species all known from the Dominican amber deposits on Hispaniola?
 * ... that Deicke and Millbrig bentonite layers in eastern United States were formed by huge volcanic eruptions?
 * ... that the oldest known member of the mayfly family Neoephemeridae is the Eocene species Neoephemera antiqua?
 * ... that fossils of the extinct reptile Acallosuchus were found in a cigar box in 1983?
 * ... that the ancient city of Tikal (pictured) in Guatemala was one of the most powerful kingdoms of the ancient Maya civilization?


 * ... that New York's Potsdam Sandstone was deposited in rising seas and consists of sediments eroded from unvegetated terrestrial landscapes?
 * ... that Termitaradus protera was the first termite bug found in amber?
 * ... that both Fordilla and Pojetaia, Cambrian members of the extinct bivalve family Fordillidae, are part of the Turkish small shelly fauna?
 * ... that although Massachusetts is located at the 42nd parallel north, some of its rocks originated near the South Pole?A
 * ... that Ekgmowechashala was the only North American genus of primate during the Late Oligocene?
 * ... that the hypothesis that the pachycephalosaurian dinosaurs used their domed skulls in head-butting competitions was first proposed in a work of science fiction?
 * ...that Terminonatator ponteixensis is the type and only species described for Terminonatator, a genus of elasmosaurid plesiosaur from Late Cretaceous of Saskatchewan, Canada?
 * ... that more than 7,000 years of artifacts have been found at the Ennis Archaeological Site in Indiana?
 * ... that both the Adena and the Hopewell left artifacts at southwestern Ohio's Beam Farm?
 * ... that Tikal Temple IV, a Maya pyramid in Guatemala, was one of the tallest structures in the pre-Columbian New World?
 * ...that an effigy mound in the shape of a turtle is located in the Beattie Park Mound Group in downtown Rockford, Illinois?
 * ... that the fossil mantidfly Dicromantispa moronei was first described from a single specimen in a private collection?
 * ... that Native Americans lived at the Canfield Island Site (pictured) on the West Branch Susquehanna River in Pennsylvania for thousands of years, and now hold an annual pow wow there?
 * ... that the extinct Miocene age maple Acer smileyi has been classified as closely related to the living Acer nipponicum (pictured)?
 * ... that Mound 72 (pictured) at Cahokia in pre-Columbian western Illinois was the site of ritual human sacrifice, including a pit burial containing 53 young women?
 * ... that the Stonerose fossil site contains the earliest known records of Rosaceae, the rose family?
 * ... that the extinct Syndesus ambericus is the only stag beetle known from the Caribbean?
 * ... that Archaeomarasmius, Aureofungus, Coprinites, and Protomycena are the only four genera of agaric mushrooms known from the fossil record?
 * ... that unlike the living golden-club Orontium aquaticum (pictured), the extinct species Orontium mackii may not have needed wetlands to grow?
 * ... that the scorpionfly family Eorpidae has a single genus, Eorpa, described in 2013?
 * ... that highlights from 19th century ichnology include the discovery of protomammal tracks in England, dinosaur footprints in Massachusetts, and the mysterious hand-shaped Chirotherium tracks (pictured)?
 * ...that the proglacial lakes of Minnesota were massive freshwater lakes covering many times the area of the Great Lakes at the end of the Wisconsin glaciation?
 * ... that German epigrapher Nikolai Grube co-presented workshops teaching Maya hieroglyphs to native Maya in Mexico and Guatemala?
 * ... that more than half of the Kappa V Archaeological Site (flooding pictured) has been destroyed by wave wash erosion?
 * ... that the fossil yew Taxus masonii was described from fifteen fossils collected from 1942 to 1989?
 * ...that Tomotley, a Native American historic site in Monroe County, Tennessee, is currently submerged by an artificial lake?
 * ... that during the 20th century, the first large-scale excavation of dinosaur footprints was undertaken in Texas for an exhibit at the American Museum of Natural History?
 * ... that the extinct plant genus Dillhoffia can't be placed into a flowering plant family at this time?
 * ... that Indiana`s Epsilon II is a rare example of a well-preserved upland archaeological site from the Archaic period?
 * ... that T. Rex and the Crater of Doom details the development of the hypothesis that dinosaurs were wiped out by a meteor impact?


 * ... that unlike modern Sassafras, which are deciduous, the extinct species Sassafras hesperia (fossil pictured) may have been evergreen?
 * ...that William King Gregory, a leading authority on vertebrate evolution and the preeminent expert on human dentition, was initially taken in by the Piltdown Man, a hoax which was purported to be an early human?
 * ... that this month celebrates the 100th anniversary of the discovery of the main Burgess Shale locality?
 * ... that the extinct ant Anochetus conisquamis is noted for having a nipple-shaped spine?
 * ... that despite heavy European and other influences, Mexican pottery and ceramics still retain indigenous elements?
 * ... that at some Maya cities, the earliest production of stone stelae coincided with the establishment of dynastic rule?
 * ... that the extinct Hydriomena? protrita was the first geometer moth to be described from the American fossil record?
 * ... that the discovery of the fossil giant ant Titanomyrma (pictured with a hummingbird) in Wyoming indicates that warmth-loving fauna spread through the north between Europe and America during hot spells in the Eocene?
 * ... that the Museo Regional de Arqueología in La Democracia, Guatemala, was founded to house artefacts collected from the local cotton plantations?
 * ...that Pachycheilosuchus, an Early Cretaceous crocodile relative, was less than a meter (3.3 ft) long and had an armored neck?
 * ... that the ichnogenus Chondrites (pictured) can be used as an indicator of anoxia in sediments?
 * ... that Kendallina, a genus of trilobite, lived in North America during the Upper Cambrian?
 * ... that the recently named trematopid temnospondyl Fedexia was named after the shipping service FedEx, which owned the land where the holotype specimen was found?
 * ... that the extinct Eocene maple species Acer rousei is a possible ancestor to the vine maple?
 * ...that Madison Limestone, a layer of mostly carbonate rocks formed in the Mississippian period, serves as an aquifer and an oil reservoir in the Rocky Mountains and Great Plains areas?
 * ... that the "Bottoms" of Milford, Ohio, contain a Woodland period archaeological site?
 * ... that the extinct Neocorynura electra, found in Dominican  amber, is the only  known species of Neocorynura "sweat bee" from the Greater  Antilles?
 * ... that the Ka'Kabish archaeological site in Belize has revealed evidence of a Mayan city?
 * ... that the extinct ants Azteca alpha carried larvae of the nematode Formicodiplogaster myrmenema?
 * ... that the pattern of the veins on fossil leaves of the extinct golden-club Orontium wolfei confirm it as a member of the arum family?
 * ... that the geology of North America includes the core of the supercontinent Laurentia?
 * ... that the fossil scorpion fly Holcorpa was described in 1878 but the family Holcorpidae not until 1989?
 * ... that the fossil big-headed fly Priabona is named for the age of the rocks in which it was found?
 * ... that the final version of the 33 m Temple 33 at the ancient Maya city of Tikal in Guatemala was completely destroyed by archaeologists in 1965?
 * ... that artefacts of the poorly understood Mezcala culture of western Mexico were re-used by the Aztecs?
 * ... that Leptofoenus pittfieldae is the only species of Leptofoenus documented from the West Indies and the only member of Leptofoenus in the fossil record?
 * ...that the Stanfield-Worley Bluff Shelter, an important Paleo-Indian site in Alabama, yielded over 11,000 artifacts ranging up to 9,000 years of age?
 * ... that a Kitkehahki Pawnee village  in Nebraska is the site where Zebulon Pike convinced the Kitkehahki to remove a Spanish flag and display an American flag?
 * ... that the Rice Northwest Museum of Rocks and Minerals in Hillsboro, Oregon, is the biggest of its kind in the Pacific Northwest?
 * ... that Cowan Creek Circular Enclosure in Ohio was once part of a group of archaeological sites that has since been submerged by a reservoir?
 * ... that Ohio's first archaeological investigation was conducted at the Marietta Earthworks?
 * ... that seeds of the fossil yew genus Diploporus are larger than Taxus seeds and smaller than Torreya seeds?
 * ... that Pseudarmadillo tuberculatus was one of two Pseudarmadillo species described in 1984 from fossils in Dominican amber?
 * ...that the University of Cambridge denied Edward A. Irving a PhD when he submitted evidence supporting continental drift?
 * ... that the extinct sawfly Pseudosiobla cambelli is one of three species of Pseudosiobla known from the fossil record?
 * ... that Takalik Abaj, an archaeological site in lowland Guatemala, has one of the greatest concentrations of Olmec-style sculpture outside of the Gulf of Mexico coast?
 * ... that Marshman Edward Wadsworth served as president of the Michigan Mining School and as State Geologist of Michigan at the same time?
 * ... that the distinct fauna of the Kirtlandian includes the dinosaur Pentaceratops sternbergii?
 * ... that highlights from the history of ornithomimosaur research include the ostrich-like Ornithomimus (skeletal mount pictured), an Archaeornithomimus bonebed in Mongolia, and the bizarre, giant-armed Deinocheirus?
 * ... that the fossil horse Scaphohippus became extinct when tectonic barriers between the Great Plains and Great Basin of North America disappeared about 13 million years ago?
 * ... that the stems in the pseudo-trunk of the extinct fern Tempskya decayed as the plant matured, leaving a layer of adventitious roots behind?
 * ... that the Paleocene Alaskan maple Acer alaskense was described from a fossil leaf that may be atypical for the species?
 * ... that of the three described species in the Eocene bulldog ant genus Avitomyrmex, one species is known only from worker caste individuals?
 * ... that paleoecologist Heinz Lowenstam discovered that living organisms can produce magnetite within their bodies?
 * ... that the Maya archaeological site of Tres Islas in Guatemala has an alignment of monuments that imitates an architectural group at Uaxactun that served as an astronomical observatory?
 * ... that Arthropleuridea is an extinct class of myriapods which includes, at over 2 meters long, the largest terrestrial arthropods that ever lived?
 * ... that the extinct fern Wessiea is known from Miocene fossils found at the "Ho ho" locality in Yakima County, Washington?
 * ... that the extinct species Cornus piggae has fruits smaller than any other species in the dogwood subgenus of Cornus?
 * ... that Obamadon was an extinct lizard that was named after President Barack Obama as a tribute to his "role model of good oral hygiene for the world"?
 * ... that the extinct Actinidia oregonensis was the first kiwi relative described from North America?
 * ... that fossils of the extinct sumac Rhus malloryi (pictured) were first published in 1935?
 * ... that the ant Aphaenogaster amphioceanica (pictured) is in the same amber fossil as six Pseudarmadillo cristatus woodlice?
 * ... that unlike its modern-day relative the gharial, the extinct crocodilian Aktiogavialis lived in saltwater?
 * ... that the fossil ant Aphaenogaster donisthorpei was once part of the Samuel Hubbard Scudder insect collection?
 * ... that a fossil flower of the extinct palm Roystonea palaea shows damage possibly made by a bat or bird?
 * ... that the only close modern relative to the fossil ant Eulithomyrmex is Tatuidris?
 * ...that naturalist Remington Kellogg used his time serving in France during World War I to collect specimens for universities in the United States?
 * ... that fossil collectors often call Polyptychoceras vancouverensis the "paperclip ammonite" or the "candy cane", due to its shape?
 * ... that Titanoceratops was known from an almost complete skeleton that was assigned to Pentaceratops, and that the two were only distantly related?
 * ... that biological anthropologist David Tab Rasmussen enjoyed working in the Neotropics because it allowed him to study both primates and birds, his two favorite subjects?
 * ... that the extinct witchalder Fothergilla malloryi (pictured) is the oldest confirmed member of the genus Fothergilla?
 * ... that excavation at the Ashworth Archaeological Site in Indiana was halted because of the owner's religious beliefs?
 * ... that the extinct Chamaecyparis eureka is the oldest confirmed member of the genus Chamaecyparis?
 * ... that the extinct ants Azteca alpha carried larvae of the nematode Formicodiplogaster myrmenema?
 * ... that the Mesa Oil Field is within the Sespe and Vaqueros Formations, which together form the second-most-prolific oil-producing geologic unit in Southern California?
 * ... that a human skull was found from the Ratcliff Site "perforated with seven holes, and had evidently been held as a trophy, the holes being the score of enemies slaughtered in battle by the wearer"?
 * ... that Fig Island includes one of the largest and most complex Late Archaic shell rings in North America, and one of the best preserved circular shell rings?
 * ...that Cetartiodactyla is a hypothesis based on DNA that suggests whales and hippos are related?
 * ...that the only excavated stand-alone timber circles in the British Isles are those at Seahenge in Norfolk and the early phases of The Sanctuary in Wiltshire?
 * ... that the big-headed fly Metanephrocerus belgardeae expanded the known range for the genus to North America?
 * ... that pottery from the Duffy Archaeological Site in Illinois is distinctive for its lack of decorative elements?
 * ... that it has been suggested the extinct palm genus Palaeoraphe was restricted to the Greater Antilles?
 * ... that the Lind Coulee Archaeological Site provided the first evidence of ancient human occupation of Washington, U.S.?
 * ... that Juan Pedro Laporte was described in an obituary as the father of Guatemalan archaeology?
 * ... that the fossil ant Apterostigma eowilsoni had good stereoscopic vision but poor side vision?
 * ... that some of the Sugar Grove Petroglyphs have been interpreted as showing Ojibwe themes, although the Ojibwe never lived near the petroglyph site?
 * ... that the extinct sandfly species Lutzomyia adiketis is host to the Paleoleishmania species P. neotropicum?
 * ... that the extinct lacewing Ainigmapsychops takes part of its name from the Greek word for enigma?
 * ... that the Anasazi Heritage Center in the U.S. state of Colorado has two pueblos dating back to the 12th century?
 * ... that the Lost World (pictured) at the ancient Maya city of Tikal was the first architectural complex to be built at the city?
 * ... that Yaxha, the third largest Maya ruin in Guatemala, is one of very few Maya cities to have built a twin pyramid complex, an architectural arrangement characteristic of Tikal?
 * ... that the extinct Lotus Nelumbo aureavallis is known from Eocene rocks in western North Dakota?
 * ... that three Adena burial mounds (one pictured) are scattered around the village of Zaleski, Ohio?
 * ... that cycloids are believed to have been driven to extinction when crabs spread across their territory?
 * ... that the extinct Cuban condor Gymnogyps varonai may have fed on ground sloths?
 * ... that seeds of the extinct tree Eucommia montana are found from British Columbia to Colorado?
 * ... that Mill Creek chert was one of the major exported raw materials of the Mississippian culture?
 * ... that the only known specimen of the early crocodile relative Stegomosuchus was kept in the discoverer's yard for several years before being given over for study?
 * ... that the king of gore and the monstrous murderer lived in Utah 80 and 75 million years ago respectively?
 * ... that the extinct paddlefish Paleopsephurus was first described from the Cretaceous Hell Creek Formation?


 * ... that the extinct witch-hazel Langeria is named for American philosopher Susanne Langer?
 * ... that the extinct Miocene hickory Carya washingtonensis is known from over 50 nuts found as a rodent cache within a petrified stump?
 * ... that the 60 million years old Carmelo Formation (pictured) is made out of thousands of layers of volcanic pebbles, sandstone and mudstone with fossils?
 * ... that the Late Eocene marine Hoko River Formation is noted for producing crab, gastropod, cephalopod, and wood fossils?
 * ... that an early nineteenth-century Native American man refused to ascend Spanish Hill because he feared a spirit that "made holes through Indians' bodies"?
 * ... that Okmulgee State Park (pictured) in Oklahoma is one of only a few places in the world where the fossil coral Gymnophyllum wardi is found?
 * ... that the extinct mantidfly Dicromantispa electromexicana was described from a solitary male insect?
 * ...that the earliest fossil reef formations that show high biodiversity, containing the earliest corals, form the mid-Ordovician Chazy Formation, reaching from Tennessee to Labrador?
 * ... that the Sterling Hill Mining Museum (pictured) and the nearby Franklin Mine together have over 345 minerals, including 90 that fluoresce and 35 that are found nowhere else?
 * ... that Aquilops ("eagle face") is the most ancient definite neoceratopsian discovered in North America?
 * ...that the Choristodera are extinct reptiles that lived during the time of the dinosaurs and have a skull structure similar to that of the modern day Gharial?
 * ... that, when described, the brown lacewing species Wesmaelius mathewesi was the most ancient member of its subfamily?
 * ... that fossils of 23 mammal species including mammoth, dire wolf, giant ground sloth, pre-historic bison, camel, and horse have been found at Fossil Lake in south central Oregon?
 * ... that the extinct sandfly species Lutzomyia adiketis is host to the Paleoleishmania species P. neotropicum?
 * ... that the early Oligocene maple, Acer ashwilli, is known from only eight places in Oregon?
 * ... that scholarly estimates for the dates of southeastern Illinois' Hubele archaeological site vary by 1,400 years from earliest to latest?
 * ... that a fossil of the extinct sea scorpion Eurypterus (restoration pictured) was once thought to be a catfish?
 * ...that the prehistoric badger genus Chamitataxus lived during the Late Miocene and is considered the most primitive badger genus in North America?
 * ... that the extinct Canadian redwood Metasequoia foxii was described from over 10,000 fossils?
 * ...that the extinct species of Edaphodon, a type of rabbitfish related to the shark, grazed along the bottom of the ocean like land-dwelling herbivores do now?
 * ... that members of the extinct bivalve family Bakevelliidae have shells made from rectangular calcium prisms and mother of pearl?
 * ... that the early dinosaur-like animal Lagerpeton was only 70 cm long?
 * ... that leaves of the fossil maple Acer palaeorufinerve resemble the living redvein maple?
 * ... that Paul S. Martin and Paul Sidney Martin both worked as anthropologists at the University of Arizona in the early 1970s?
 * ... that Protostephanus was the first extinct wasp genus in the family Stephanidae to be described from a fossil?
 * ... that archaeologists found pottery shards at the Bowen site linking it to the Oliver Phase of woodland culture development?
 * ... that a new twin pyramid complex (east pyramid pictured) was built at the Maya city of Tikal every twenty years to celebrate the end of a Maya calendrical cycle?
 * ... that highlights from the history of ceratopsian research include the discovery of the iconic Triceratops (skeletal mount pictured), spike-frilled Styracosaurus, and vast bonebeds preserving thousands of Centrosaurus?
 * ... that the extinct crab Metacarcinus starri from Washington state is related to the graceful rock crab?
 * ... that the 500-million-year-old Cambrian predator Hurdia was thought to be a number of separate organisms for 100 years, until the complete animal was reconstructed in March 2009?
 * ... that the extinct ant Anochetus lucidus is named for its shiny exoskeleton?
 * ... that the first woman elected to the Geological Society of America, Mary Emilie Holmes, was also one of the cofounders of a historically black college?
 * ... that at least one species of the extinct termites Parastylotermes (fossil pictured) was found in the Calico Mountains?
 * ... that the Stoner archaeological site in Illinois is unusual for its lack of evidence of substantial occupation by any people other than the Allison-Lamotte culture?
 * ... that siltstone deposits have allowed three-dimensional fossils of the extinct mushroom crinoid to be excavated from Indiana?
 * ... that the extinct maple section Torada is only known from the three Eocene species A. stonebergae, A. toradense, and A. washingtonense?
 * ... that the type specimen of the extinct whip scorpion Graeophonus carbonarius was originally identified as a species of dragonfly?
 * ... that Tyrannasorus rex had wings and six legs?
 * ... that "color markings", considered rare among fossil crabs, have been found on Avitelmessus?
 * ... that the paleobotanists David P. Penhallow and Chester A. Arnold both published studies on the extinct water-fern Azolla primaeva?
 * ... that this rockshelter (pictured) may have been inhabited more than ten thousand years ago?
 * ... that Carnufex is an extinct relative of crocodiles that lived 231 million years ago in Carolina?
 * ... that out of about 20,000 Clarno Formation fossils, only 5 were from the extinct dogwood Cornus clarnensis?
 * ... that the Queenston Formation (outcrop pictured) is used by the ceramic industry in the Canadian province of Ontario and for natural gas production in the U.S. state of New York?
 * ... that the fossil ant genus Archiponera is known from a single pair of fossils described in 1930?
 * ... that the extinct species Agulla mineralensis is the first North American snakefly to be described from Neogene fossils?
 * ... that archaeologist Vance Haynes challenged the right of Native Americans to rebury Kennewick Man—skeletal bone fragments about 9,000 years old—which Haynes said should be studied further?
 * ... that Acer castorrivularis is one of five extinct maples from the Eocene Beaver Creek flora in Montana?
 * ... that the extinct Cretaceous wasp family Plumalexiidae is known from only the two Plumalexius type specimens found in New Jersey amber?
 * ... that highlights from the history of ichthyosaur research (example pictured) include fossils of pregnant females, whale-sized ichthyosaurs from Nevada, and ichthyosaurs with swordfish-like jaws?
 * ... that Entropezites, Mycetophagites, and Palaeoagaracites present the oldest evidence of fungal parasitism and hyperparasitism by other fungi in the fossil record?
 * ... that fossils of the extinct legume Hymenaea mexicana show several types of insect feeding?
 * ... that the only known specimen of the extinct spider Palaeoperenethis is in the Royal Ontario Museum?
 * ... that T. Rex and the Crater of Doom details the development of the hypothesis that dinosaurs were wiped out by a meteor impact?
 * ... that the Ellerbusch Archaeological Site in the U.S. state of Indiana was picked for extensive excavation partly because it was so small?
 * ... that, in the late 8th and early 9th centuries, the Maya city of Sacul was one of the few kingdoms in the southeastern Petén region to use its own Emblem Glyph?
 * ... that the Stoner archaeological site in Illinois is unusual for its lack of evidence of substantial occupation by any people other than the Allison-Lamotte culture?
 * ... that highlights from the history of dromaeosaurid research include a skeleton of Velociraptor preserved in combat with a Protoceratops, the gigantic Utahraptor, and tiny four-winged Microraptor?
 * ... that the extinct Eocene maple Acer republicense is known from only one fossil seed?
 * ... that the Museo Regional del Sureste de Petén in Guatemala was built to offset damage from a highway construction project?
 * ... that the fossil stick insect Eoprephasma was described from two isolated forewings?
 * ... that the extinct North American Oligocene-age vulture Phasmagyps may be the oldest New World vulture?
 * ... that the extinct ant Acanthostichus hispaniolicus is the only Acanthostichus species found in the West Indies?
 * ... that Frederic Brewster Loomis uncovered vertebrate fossils that were still exhibited at Amherst College's Beneski Museum of Natural History almost a century later?
 * ... that the Permian amphibian Trimerorhachis either brooded young in its mouth or ate them?
 * ... that extinct diadectid reptiliomorphs (life restoration pictured) were the first large herbivorous land animals?
 * ... that Mayan eccentrics (pictured) were often buried under monuments and buildings?
 * ... that the extinct mantidfly Feroseta prisca has bristle-covered pterostigma?
 * ... that Gerobatrachus is considered to be a missing link that supports the hypothesis offered by cladistics, that frogs and salamanders had a common ancestor?
 * ... that potbelly sculpture is a crude non-Maya sculptural style distributed along the Pacific slope of southern Mesoamerica and dating to the Preclassic Period?
 * ... that shartegosuchid crocodyliforms made up an endemic Central Asian Mesozoic fauna that existed after the breakup of Pangaea?
 * ... that the fordilloid Camya asy is one of four accepted Cambrian bivalves?
 * ... that the fossil butterfly Prodryas persephone (engraving pictured) is so well preserved that individual wing scales can be seen?
 * ... that the extinct arachnid Attercopus was once considered as the world's oldest spider?
 * ... that modern humans have been found to inhabit various countries for periods ranging from almost 200,000 years to less than 800 years?
 * ... that the extinct planthopper Tainosia quisqueyae was named for the Taíno people and Hispaniola?
 * ... that Hidden Cave, an archaeological cave site located in the Great Basin near Fallon, Nevada, got its name because its entrance was difficult to find?
 * ... that Mill Creek chert was one of the major exported raw materials of the Mississippian culture?
 * ... that Araneagryllus is named from a combination of the Latin aranea meaning "spider" and gryllus meaning "cricket"?
 * ... that many of the pre-Columbian Etowah plates found at Etowah Indian Mounds in Georgia were thought to have been made at Cahokia in western Illinois?
 * ... that of the 17 confirmed Olmec colossal heads of Mexico (example pictured), the largest is estimated to weigh 40 tons?
 * ... that Mississippi's Spanish Fort is neither Spanish nor a fort?
 * ...that Fossil Cycad National Monument, established in South Dakota in 1922, was withdrawn as a national monument in 1956 because all of the visible fossils had been stolen?
 * ... that the extinct rose family member Neviusia dunthornei is one of only three known Neviusia species?
 * ... that the primary leaf veins for the extinct plant Trochodendron nastae are palmate rather than being pinnate like those in the living Trochodendron aralioides?
 * ... that amber fossils of ants carrying the extinct mealybug genus Electromyrmococcus represent the oldest record of symbiosis between mealybugs and Acropyga ants?
 * ... that the extinct Eocene maples Acer hillsi and Acer stewarti are distinguished by how inflated the nut is?
 * ... that the extinct Eocene butterfly Prodryas persephone (pictured) from the Florissant Fossil Beds is the best preserved fossil lepidopteran discovered to date?
 * ... that the first described fossil of Anochetus dubius is surrounded by a brownish bacterial growth?
 * ... that Indian Mound Cemetery, originally created by the Hopewell culture, was defended in battle by Confederate soldiers and is the last resting place of an owner of the Washington Redskins?
 * ... that American Canadian scientist Jack Souther contributed significantly to the early understanding of Quaternary volcanism in Canada?
 * ... that both Fordilla and Pojetaia, Cambrian members of the extinct bivalve family Fordillidae, are part of the Turkish small shelly fauna?
 * ...that 12,000-year-old Paleo-Indian artifacts, including a rare fluted point, have been found in a quarry near Goshen, New York?
 * ... that the fossil maple species Acer kenaicum was suggested to be an ancestor of silver maples?
 * ...that Mayanist scholar and archaeologist Sylvanus Griswold Morley was also an American secret agent in World War I?
 * ... that malacologist Myra Keen was called the "First Lady of Malacology"?
 * ... that the cretaceous subfamily Sphecomyrminae has not been included in several recent phylogenetic studies of the ant family?
 * ... that fossil specimens of the extinct scorpionfly family Dinopanorpidae, which includes Dinopanorpa and Dinokanaga, sometimes have preserved dark with light to clear color patterning?
 * ... that the long-nosed god maskettes (pictured) found throughout the American Midwest are believed to have been used in the ritual adoption of visiting tribal leaders?
 * ...that the Eva archaeological site in Tennessee was inhabited from about 6000 to 1000 BC, but it is now below water?
 * ... that the fossil sawfly species Eriocampa tulameenensis was found along the Canadian Pacific rail line near Princeton, British Columbia?
 * ... that Bertha Parker Pallan (pictured) was one of the first female Native American archaeologists?
 * ... that both Fordilla and Pojetaia, Cambrian members of the extinct bivalve family Fordillidae, are part of the Turkish small shelly fauna?
 * ... that the type specimen of the extinct bulldog ant Macabeemyrma ovata is the fossilized remains of an adult queen preserved in shale?
 * ... that occupation of the La Soledad de Maciel archeological site in Guerrero, Mexico, lasted for over 3,000 years?
 * ... that squash remains at Guilá Naquitz Cave are the oldest known evidence of crop domestication in the Americas?
 * ... that the ruins of the Maya city of Mixco Viejo in Guatemala received their name because they were believed to be the remains of another city entirely?
 * ... that Gerard Fowke spent much of his life studying ancient burial mounds, trying to prove the existence of a civilization that predated what we currently understand to be the Native Americans?
 * ... that the Wishram Indian Village Site is believed to have been occupied for at least 10,000 years?
 * ... that coal balls are not made of coal?
 * ... that the extinct Jamaican Flightless Ibis developed unique club-like wings that could be used as a flail?
 * ... that plates in the pre-Columbian Wulfing style, likely made by the same workshop at Cahokia, have been found as far apart as Oklahoma, Illinois, and Florida?
 * ... that Puppigerus, an extinct sea turtle, had a specialized jaw structure which kept it from accidentally inhaling water?
 * ... that the North Atlantic breakup resulted in the separation of Eurasia from North America, forming the North Atlantic Ocean?
 * ... that a mummy was found in a cave in Wyoming?
 * ... that archaeological excavations in Frightful Cave, in Coahuila, Mexico, recovered over 950 fibre sandals and the remains of an aged woman?
 * ... that over the course of the history of stegosaur research, their iconic back plates have been thought to function as armor plating, to regulate body temperature, or to attract mates?
 * ... that a new dinosaur (pictured) discovered in North and South Dakota has been nicknamed the "chicken from hell"?
 * ... that the extinct Phlebotominae sandfly Pintomyia falcaorum is known only from Miocene age Dominican amber found on Hispaniola?
 * ... that the extinct ant Anochetus exstinctus was described from only two of the three fossils known to the species author?
 * ... that the Lake Murray Meteorite, discovered in 1933, is the largest Class IIAB octahedrite found in Oklahoma and the fifth largest found in the world?
 * ...  that Archiinocellia   is noted to be the only snakefly fossil genus from British Columbia and one of only two from Canada?
 * ... that the Triassic archosaur Poposaurus walked on two legs like some dinosaurs, but was more closely related to crocodiles?
 * ... that the Klondike Mountain Formation has fossil hot springs and is a lagerstätten?
 * ... that Siats, named after a man-eating monster, is the geologically youngest North American allosauroid yet discovered?
 * ... that the extinct Miocene redwood, Sequoiadendron chaneyi, is the probable ancestor to the giant sequoias in California?
 * ... that the extinct genus Paleopanax is one of the oldest reliable records for the ginseng family?
 * ... that excessive nutrients from volcanoes caused the loss of oxygen in the Western Interior Seaway which linked the Caribbean to the Arctic?
 * ... that at the inauguration of the sixth Aztec Templo Mayor in 1487 (scale model pictured), thousands of prisoners of war were ritually sacrificed, bathing the steps of the pyramid in blood?
 * ... that the Maya city of La Blanca in northern Guatemala features an unusually well built palace complex for such a small city?
 * ... that the extinct maple Acer dettermani is only known from the flank of a volcano?
 * ... that the Triassic reptile Vancleavea, which is specialized to live in the water, differs greatly from all other early archosauriforms?
 * ... that the extinct legume Hymenaea allendis is the second Hymenaea species described from Mexican amber?
 * ... that fossils of the extinct bivalve family Praenuculidae have been found on every continent except Antarctica?
 * ... that the extinct ant Anochetus intermedius had mandibles longer than its head?
 * ... that the Late Triassic archosauromorph Uatchitodon is the earliest known venomous reptile?
 * ... that the Miocene ant Acropyga glaesaria is one of the oldest examples of trophobiosis?
 * ... that the extinct snakefly Agulla protomaculata is the only snakefly described from the Green River Formation?
 * ... that with a 20 million year fossil record, Acer chaneyi has the longest fossil record of the Western North American maples?
 * ...that Spanish artifacts excavated at Citico, Tennessee suggest that the historic Native American site may have been the village of "Satapo" visited by the Juan Pardo expedition in 1567?
 * ... that the practice of insect husbandry by ants is at least 15 million years old?
 * ... that the fossil maple Acer taurocursum is named for its type locality, the "Bull Run flora"?
 * ... that the Hovey Lake Archaeological District in Indiana's southwestern corner is endangered by flooding, oil derricks, bird hunters, and vandals?
 * ... that the extinct giant ant genus Formicium is known only from forewings found in Dorset, England and Tennessee, US?
 * ...that British archaeologist J. Desmond Clark discovered a site at Zambia's Kalambo Falls containing artifacts from over 250,000 years of human culture?
 * ...that fossil Thelodont fish (depiction pictured) surprised scientists by showing that stomachs evolved before jaws?
 * ... that the extinct ant Acanthognathus poinari had jaws like its modern relatives?
 * ... that Calakmul (pictured) was one of the largest and most powerful Maya cities?
 * ...that despite being a National Historic Landmark and the site of Washington's oldest known human remains, the Marmes Rockshelter was submerged after the Lower Monumental Dam construction?


 * ... that Kenneth Feder teenage interest in the paranormal led to a career in archaeology studying it?
 * ... that the extinct buthid scorpion Uintascorpio was first placed in the family Vaejovidae?
 * ... that the earliest known Maya city in the Maya lowlands of Mesoamerica dates to around 750 BC?
 * ... that, being a descendant of Pliohippus, Astrohippus is not considered to be an ancestor to modern horses?
 * ...that some experts believe a cylinder seal (pictured) from the prehistoric San Andrés site is evidence for an Olmec writing system?
 * ...that the geology of the Grand Canyon area includes more than 40 identified rock layers?
 * ... that a petroleum geologist named William Warren Orcutt began collecting fossils from the La Brea Tar Pits in 1901, bringing the site to the attention of the scientific community?
 * ... that one archaeological site was discovered by groundhogs?
 * ... that lice from mummified guinea pigs and mites preserved in amber while feeding on spiders have provided evidence for researchers in the field of paleoparasitology?
 * ... that the first Columbian mammoth (artist's restoration pictured) found at the Snowmastodon site, an Ice Age fossil dig near Denver, was initially dug out by a construction worker using a bulldozer?
 * ... that a new species of the extinct ant Archimyrmex was described in 2012?
 * ... that Calsoyasuchus valleyceps, an extinct crocodile relative from the Early Jurassic, has a deep groove in its skull from which its species name, "valley head", derives?
 * ... that Stephen Jay Gould once called Donald Prothero "the best punctuated equilibrium researcher on the West Coast"?
 * ... that seeds of the extinct tree Eucommia eocenica have been found with latex covered fossils?
 * ... that the extinct sweat bee genus Nesagapostemon is known from a single 9.9 mm female specimen?
 * ... that the large ritual E-Group complex northeast of the ancient acropolis in the Maya city of El Chal (altar pictured) in Guatemala was once the city centre?
 * ... that the site of the aboriginal village of Nocoroco, near Ormond Beach, Florida, is marked by a large fountain sculpture, called the "Tomokie Fountain"?
 * ... that Golondrina points are considered the most prevalent of Paleo-Indian points in the South Texas Plains and typify the region's first distinguished cultural pattern?
 * ... that the extinct species Trochodendron drachuckii is known from a single Eocene fossil found near Cache Creek, British Columbia?
 * ... that Aenigmastacus, a fossil crayfish from Canada, belongs to a family only otherwise known from the Southern Hemisphere?
 * ...that the discovery of the dinosauromorph Dromomeron, from the Late Triassic of New Mexico, indicates that dinosaurs did not rapidly replace their close relatives?
 * ... that the Cranberry Creek Archeological District (pictured) contains several hundred ancient American Indian burial mounds?
 * ... that Peltandra primaeva was the first fossil record for the genus Peltandra when described in 1977?
 * ...that the Eurymedon vase has been cited as evidence of Ancient Greek sexual mores?
 * ... that highlights from the history of tyrannosaur research include the first carnivorous dinosaur known to walk bipedally, the giant Tyrannosaurus rex, and feathered taxa from China like Yutyrannus?
 * ... that highlights from the history of ankylosaur research include one of the first dinosaurs ever discovered and a dinosaur with armored eyelids?
 * ... that the main temple at the Plaza of the Seven Temples (pictured) in the Maya city of Tikal, in modern Guatemala, was decorated with a skull and crossbones?
 * ... that it is all but impossible to match up species known by leaves with those known by trunks in the prehistoric cycad-like genus Cycadeoidea?
 * ... that mitochondrial DNA testing of the 300 to 500-year-old Canadian "iceman" mummy Kwäday Dän Ts’ìnchi and current clans of British Columbia revealed 17 living relatives?
 * ... that findings of Cylindroteuthis and other belemnites in Greenland suggest that an early form of the Gulf Stream existed as early as the Valanginian (Early Cretaceous)?
 * ... that over 200 fossils of Aphaenogaster mayri were known when the species was described in 1930?
 * ... that the extinct brown lacewing Cretomerobius is known from both the Cretaceous and Eocene?
 * ... that, in one study on the aetosaur Redondasuchus, the orientation of a diagram in the paper may have contributed to the misidentification of its holotype as a left scute rather than a right?
 * ... that the extinct lobe-finned fish Laccognathus embryi (reconstruction pictured) had fangs up to 3.8 cm (1.5 in) long?
 * ... that the type specimen of Scolosaurus seriously injured its discoverer, who was excavating it when it fell on him?
 * ... that the Maya city of Ixkun in Guatemala erected one of the tallest stone stelae in the entire Petén Basin?
 * ... that the extinct planthopper Emiliana was described from a single 47 million year old wing?
 * ... that Tilly Edinger founded paleoneurology?
 * ... that malacologist Myra Keen was called the "First Lady of Malacology"?
 * ... that Megalictis ferox, a species of extinct predatory mustelid, resembled a modern wolverine but with three times the body mass?
 * ... that highlights from the history of hadrosaur research include the first dinosaur fossils to be mounted in a museum, the colossal Shantungosaurus, and Maiasaura nesting grounds in Montana?
 * ... that the Michigan Geological Survey severed its university affiliations in the 1890s due to perceived disadvantages of those relationships, but became part of Western Michigan University in 2011?
 * ... that Temple III at the Maya city of Tikal in Guatemala was the last pyramid ever built there?
 * ... that lice from mummified guinea pigs and mites preserved in amber while feeding on spiders have provided evidence for researchers in the field of paleoparasitology?
 * ... that Alexander Wetmore assessed the extinct Eonessa anaticula as being an ancient type of duck, possibly due to its fossil's resemblance to the modern Oxyura jamaicensis?
 * ...that the fossil of Ichthyornis (pictured) discovered by Benjamin Franklin Mudge was the first bird recognized to possess teeth?
 * ... that judging from sculptures discovered in the ancient Maya city of Río Azul, it is believed that the local elite was sacrificed after a takeover by Tikal?
 * ... that highlights from the history of troodontid research include the discovery that troodontids (example pictured) were among the brainiest dinosaurs?
 * ... that the extinct pine Pinus driftwoodensis was first described from a permineralized conifer cone in chert?
 * ... that the extinct ant species Apterostigma electropilosum was described from a solitary fossil in amber?
 * ... that multiple Leptocleidus skeletons have been found preserved as gemstone quality opal over the course of the history of plesiosaur research?
 * ... that the extinct Eocene maples Acer hillsi and Acer stewarti are distinguished by how inflated the nut is?
 * ... that fossil specimens of the extinct scorpionfly family Dinopanorpidae, which includes Dinopanorpa and Dinokanaga, sometimes have preserved dark with light to clear color patterning?
 * ... that the recently discovered Eocypselus rowei may be ancestral to both hummingbirds and swifts?
 * ... that excavations in 1887 and 1919 on Bussell Island uncovered a number of small, round graves of early inhabitants of present-day Tennessee, United States, circa 3000 BC to 1000 CE?
 * ... that the largest known ovules produced by any non-flowering seed-plant came from the Medullosales (fossilized leaves pictured), an order of extinct seed ferns?
 * ... that Hyptia deansi is the only fossil ensign wasp described from Mexican amber?
 * ... that researchers have identified the pictured life form which no longer lives on this planet?
 * ...that the cultures of the Western Mexico shaft tomb tradition not only considered dogs to be soul guides for the dead, but a major source of protein as well?
 * ... that anthropologist Therkel Mathiassen described Comer's Midden as the only substantial find of pure Thule culture in Greenland?
 * ... that at the time of the Spanish Conquest, the Kaqchikel Maya city of Iximche (pictured) was the second most important city in the Guatemalan Highlands?
 * ... that the extinct ant Anochetus corayi was the first Anochetus species described from a fossil?
 * ...that natural gas in the Marcellus Formation could increase United States energy reserves by one trillion U.S. dollars?
 * ... that out of the described snakefly specimens from the Florissant Formation, the Raphidia  funerata  holotype  is the most complete?
 * ... that the Mayan archaeological site Baking Pot covered a 9 sqkm area?
 * ... that the Mam Maya capital city of Zaculeu (fragment pictured) fell to Spanish conquistador Gonzalo de Alvarado y Chávez after a siege that lasted several months?
 * ... that the first Bayfield group quarry opened in 1868 on Basswood Island?
 * ... that Deltaterrasserne, containing features of both Independence I and Independence II cultures, is one of the largest archaeological sites in Peary Land?
 * ...that the type specimen of Dromicosuchus had damage to its jaw and neck that may have been inflicted by the teeth of the large carnivore it was found underneath?
 * ... that the extinct, Miocene age, maple Acer browni ranged from southern Oregon to the north shore of the Haida Gwaii?
 * ... that the discovery of 189 fossils of the mid-Cambrian Odontogriphus thrust it into the centre of a heated debate about the evolution of molluscs, annelids and brachiopods?
 * ... that the extinct ant Anochetus brevidentatus was the second Anochetus species described from Dominican amber?
 * ... that it may not be possible to determine what ?Oryzomys pliocaenicus is?
 * ... that the Makauwahi Cave has been described as "...maybe the richest fossil site in the Hawaiian Islands, perhaps in the entire Pacific Island region"?
 * ... that the name for the extinct birch family genus Kardiasperma is from the Greek words for "heart" and "seed"?
 * ... that the widowed philanthropist Mary Hemenway (pictured), impressed with Frank Cushing's anthropological work among the Zuni, sponsored the Hemenway Southwestern Archaeological Expedition?
 * ... that one species of the extinct bivalve Similodonta was found in 108.90 m down a Welsh borehole?
 * ... that Canadian paleontologist Scott D. Sampson hosted the four episode nature documentary series Dinosaur Planet for the Discovery Channel in 2003?
 * ... that the type specimen of the extinct tortoise beetle Denaeaspis is only 6.04 mm long?
 * ... that the extinct termite bug Termitaradus dominicanus is divided into fourteen brown lobes?


 * ... that Paul S. Martin and Paul Sidney Martin both worked as anthropologists at the University of Arizona in the early 1970s?
 * ... that fossils of Eucommia constans are the youngest and most southerly examples of Eucommia in North America?
 * ... that the Eocene maple Acer clarnoense is not found in the Clarno Formation even though the species was named after it?
 * ...that the mounds of Indian Mound Park on Dauphin Island, Alabama are composed of oyster shells discarded over centuries by migrant Indians?
 * ... that the early Eocene maple species Acer douglasense is the second-oldest maple known from Alaska?
 * ... that Xochipala-style figurines (pictured) are considered some of the earliest and most naturalistic in Mesoamerica?
 * ... that archeologist Anna Curtenius Roosevelt, the great-granddaughter of Theodore Roosevelt, described a pre-Columbian civilization in Brazil as having "outstanding indigenous cultural achievements"?
 * ... that Urocyon progressus, a species of extinct fox, was formally described after two bones and a tooth were found?
 * ... that the extinct Pliocene pine Pinus matthewsii is thought to have been a colonizing tree?
 * ... that the extinct fly Schwenckfeldina archoica has spines on its genitalia?
 * ... that Swan's Landing on the Ohio River in southern Indiana is one of the most important Late Archaic archaeological sites in North America?
 * ...that Ammosaurus remains were originally mistaken by Othniel Charles Marsh as those of another dinosaur, Anchisaurus?
 * ...that Stegosaurus, one of the most distinctive dinosaurs, has been widely depicted in popular culture?
 * ... that bones of Hypsibema missouriensis, now the state dinosaur of Missouri, have only been found in Bollinger County, Missouri?
 * ... that bones of Hypsibema missouriensis, now the state dinosaur of Missouri, have only been found in Bollinger County, Missouri?
 * ... that the private Miraflores Museum in Guatemala City has three mounds from the ancient Maya city of Kaminaljuyu in its grounds?
 * ...that Sue (pictured) is the largest, most complete, and best preserved Tyrannosaurus rex fossil ever found?
 * ... that the 110-foot (34 m) fresco The Age of Reptiles is the largest painting on the subject of natural history in the world?
 * ...that Sue (pictured) is the largest, most complete, and best preserved Tyrannosaurus rex fossil ever found?
 * ... that the 110-foot (34 m) fresco The Age of Reptiles is the largest painting on the subject of natural history in the world?
 * ...That the Tibes Indigenous Ceremonial Center located in Ponce, Puerto Rico, is the oldest astronomical observatory in the Caribbean?
 * ... that six prehistoric meteorite impacts have created large astroblemes affecting the geology of Saskatchewan?
 * ... that Peloroplites was one of the largest nodosaurid dinosaurs, and came from a time when armored dinosaurs in general were attaining large sizes?
 * ...that the newly-named Oryctodromeus, a genus of small herbivorous dinosaur from the mid Cretaceous of Montana, is the first dinosaur described as making burrows?
 * ... that a new dinosaur (pictured) discovered in North and South Dakota has been nicknamed the "chicken from hell"?
 * ...that American lions were probably cave lions who crossed the Bering land bridge into Alaska?
 * ... that paleobotanist Shya Chitaley named an extinct plant species for Cleveland's bicentennial and also had an extinct plant species named for her?
 * ... that the fossil bee Anthophorula persephone is named for a Greek goddess?
 * ...that the mummified fossil of an Edmontosaurus annectens was secured by the American Museum of Natural History for $2,000?
 * ... that the Corythosaurus (mounted skeleton pictured) bore a tall, elaborate bony crest atop its skull, which contained elongate nasal passages?


 * ... that the dinosaur Wendiceratops (pictured) was named for fossil hunter Wendy Sloboda, who then had it tattooed on her arm in celebration?
 * ... that the king of gore and the monstrous murderer lived in Utah 80 and 75 million years ago respectively?
 * ...that Dracorex hogwartsia was a dinosaur named for its resemblance to the Hungarian Horntail, a dragon in J.K. Rowling's Harry Potter series?
 * ...that Dracorex hogwartsia was a dinosaur named for its resemblance to the Hungarian Horntail, a dragon in J.K. Rowling's Harry Potter series?
 * ...that Dracorex hogwartsia was a dinosaur named for its resemblance to the Hungarian Horntail, a dragon in J.K. Rowling's Harry Potter series?
 * ... that the North Acropolis (pictured) at the ancient Maya city of Tikal served as a royal necropolis and contains the tombs of a number of identified Maya rulers?
 * ... that the Triassic archosaur Poposaurus walked on two legs like some dinosaurs, but was more closely related to crocodiles?
 * ...that the discovery of the dinosauromorph Dromomeron, from the Late Triassic of New Mexico, indicates that dinosaurs did not rapidly replace their close relatives?
 * ... that Macroelongatoolithus is a kind of giant fossil egg that can be over 60 cm long, and probably was laid by a gigantic oviraptorid?
 * ...that the dinosaur fossil Dakota is so well-preserved it has caused researchers to revise their estimates of the appearance, size, and speed of a whole group of dinosaurs known as hadrosaurs?
 * ...that the freshwater weed Azolla may have grown in the Arctic Ocean with enough vigour to plunge the world into an ice age?
 * ...that Othniel Charles Marsh named two species of the dinosaur Coelurus from the same quarry, not knowing that the bones belonged to the same skeleton?
 * ...that species of Prosaurolophus, a duckbilled dinosaur, have been described by Barnum Brown and Jack Horner, two of the most prominent paleontologists of the 20th century?
 * ... that the Maya city of Kinal in northern Guatemala possessed an unusually complex acropolis but is noted for its complete absence of sculpted stelae and altars?
 * ...that the funerary art (pictured) of many cultures includes psychopomps, like the Zapotec bat god, who conduct souls to the afterlife?
 * ... that in ancient Mesoamerica, mirrors were fashioned from stone and were regarded as portals to a supernatural realm?
 * ... that the Paleocene Ginkgo cranei is the first fossil Ginkgo to be described from Tertiary "seeds"?
 * ... that microbial mats increase our understanding of evolution by helping to preserve soft-bodied organisms and soft parts of hard-shelled animals?
 * ... that the Early Permian microsaur Rhynchonkos (pictured) shares many similarities with Eocaecilia, and may be an ancestor of caecilians?
 * ... that Arizonasaurus had a large sail along its back made of the spines on its vertebrae?
 * ... that for most of its history, Ixtonton was the most important Maya city in the upper Mopan Valley of Guatemala?
 * ... that historical therizinosaur research misinterpreted these unusual bird-like herbivorous dinosaurs as giant turtles, semiaquatic fish-eaters, and tree-climbing insectivores?
 * ...that ostracoderms are the earliest known vertebrate animals?
 * ... that the name Ginkgo dissecta was first coined in 1974 but not formalized until 2002?
 * ...that artifacts discovered at Mound Bottom, Tennessee show that the site was part of a vast Native American trading network extending to the Great Lakes, the Gulf of Mexico, and the Appalachian Mountains during the Mississippian era?
 * ... that the shrimp-like 510-million-year-old arthropod Waptia (artist's restoration pictured) was named after two mountains?
 * ...that Town Creek Indian Mound near Mount Gilead, North Carolina, preserves a ceremonial mound built by the Pee Dee with 563 burials?
 * ... that there are Dinosaur Footprints in the Connecticut River Valley?
 * ... that Temple II, the most thoroughly restored pyramid at the Maya ruins of Tikal in Guatemala, was probably built by king Jasaw Chan K'awiil I to honour his wife, Lady Kalajuun Une' Mo'?

Selected pictures
Cast of the skull and neck vertebrae of a Uintatherium anceps. The specimen was a gift from Professor Othniel Charles Marsh to the Museum National d'Histoire Naturelle of Paris, France in 1889. Photo credit: Jebulon

Mounted skull and neck of the 150 million year old Late Jurassic theropod Allosaurus fragilis. The specimen was discovered in the US state of Utah and is exhibited in the Galerie de paléontologie et d'anatomie comparée of the Muséum National d'Histoire Naturelle in Paris, France. Photo credit: Jebulon Rock formations known as the Tepees in Petrified Forest National Park Arizona, USA. The exposed rock layers belong to the Blue Mesa Member of the Chinle Formation and are about 220 to 225 million years old. The colorful bands of mudstone and sandstone were laid down during the Triassic, when the area was part of a huge tropical floodplain. Photo credit: User:Finetooth

The middle of a polished 15.34 cm × 18.04 cm slice of a petrified tree from Arizona, USA. After the enlargement of the image it is possible to see insect borings in the wood. The tree lived approximately 230 million years ago during the Late Triassic. Photo credit: Michael Gäbler Close up image of petrified wood from Canyonlands National Park in Utah, USA. Photo credit: Jim Gordon Various views of a Pliocene shell of the lightning whelk Busycon contrarium from La Belle, Florida, USA. The specimen is 24 cm long. Photo credit: H. Zell

Fossil remains of various horse genera, showing the evolution of their skeletons, skulls and limb bones over time. The uppermost and most recent genus is that of the modern horse, Equus. Below that is Pliohippus, dating back to the late Miocene. Below that and older still is Merychippus of the middle Miocene. The bottom and oldest horse genus is Mesohippus from the late Eocene. Photo credit: H. Zell

A mounted skeleton of a Late Cretaceous mosasaurid species belonging to the genus Plioplatecarpus, probably P. ictericus. In life the animal would have been about 5.5 m in length. The mounted skeleton is actually a composite of two individuals collected from the Niobrara Formation, of Kansas, USA and is exhibited in the Museum für Naturkunde in Karlsruhe, Germany. Photo credit: H. Zell

A life restoration of the Late Cretaceous ceratopsid dinosaur Achelousaurus horneri from the Two Medicine Formation of Montana, USA. Artist credit: Mariana Ruiz

Fossil shells of the scaphitid ammonoids Hoploscaphites (left) and Discoscaphites (right). The shell dates back to the Maastrichtian age (66–72.1 million years ago) of the Late Cretaceous epoch. The Specimen was collected in South Dakota, USA. Photo credit: H. Zell A fossil of the asaphid trilobite Megalaspides . This specimen dates back to the Ordovician period. It was collected in Ohio, USA and is displayed by the Staatliches Museum für Naturkunde in Karlsruhe, Germany. Photo credit: H. Zell

A cluster of fossils fossil of the trilobite Homotelus bromidensis. This specimen dates back to the Ordovician period and was discovered in Oklahoma, USA. Photo credit: High Contrast

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Good prehistory of North America articles - ?Oryzomys pliocaenicus - Aetosaur - Archaeomarasmius - Chitinozoan - Cloudinid - Coal ball - Dimetrodon - Stephen Jay Gould - History of paleontology - Kirtlandian - Macabeemyrma - Megalodon - Ornatifilum - Othnielosaurus - Protomycena - Pteranodon - Pterosaur - Saint Croix macaw - Small shelly fauna - Smilodon - Temnospondyli - Tiktaalik - Waptia