User talk:Utaricaca

[edit] History

[edit] 1940s Forrest Mars, Sr., founder of the Mars Company, got the idea for the confection in the 1930s during the Spanish Civil War when he saw soldiers eating Smarties, a chocolate morsel covered with a hard sugar shell so that the chocolate would not melt.

Mars received a patent for his own process on March 3, 1941. Production began in 1941 in a factory located at 285 Badger Avenue in Clinton Hill, Newark, New Jersey. One M was for Forrest, and the other M was for Bruce Murrie, son of long-term Hershey president William F.R. Murrie.[3] Murrie had 20 percent interest in the product. The arrangement allowed the candies to be made with Hershey chocolate which had control of the rationed chocolate.[4] When operations were started, the hard-coated chocolates were made in six different colors: Brown, Yellow, Orange, Red, Green and Violet. They were served in a cardboard tube (similar to Smarties).[5]

The practicality of the candies during World War II caused an increase in production and its factory moved to bigger quarters at 200 North 12th Street in Newark, New Jersey where they remained until 1958 when it moved to a bigger factory at Hackettstown, New Jersey. During the War the candies were exclusively sold to the military.[5]

In 1948 the cardboard packaging was replaced by the black cellophane packaging. In the same year Mars bought out Murrie's 20 percent stake.

[edit] 1950s In 1950 a black "M" was imprinted on the candies. It was changed to white in 1954.[5]

In the early 1950s, the Midwest Research Institute in Kansas City, Missouri, working for M&M's perfected a process whereby 3,300 pounds of chocolate centers could be coated every hour.[6]

In 1954, Peanut Chocolate Candies were introduced, while the M&M's brand characters and the famous slogan "The milk chocolate that melts in your mouth, not in your hand" were both trademarked.

M&M's store at Florida Mall in Orlando, FL [edit] 1970s and 1980s Red candies were eliminated in 1976[7] due to health concerns over the dye amaranth (FD&C Red #2), which was a suspected carcinogen, and were replaced with orange-colored candies (this despite the fact that M&M's did not contain the dye; the action was purely to satisfy worried consumers). By 1987, the public had forgotten the scare, and the red candies were reintroduced, but they also kept the orange colored M&M's. They currently contain Allura Red AC (FD&C Red #40, E129). In Europe, Allura Red AC (E129) is not recommended for consumption by children. It is banned in Denmark, Belgium, France, Germany, Switzerland, Sweden, Austria, and Norway.[8] Instead, Cochineal (E120) is used in the red shells.

In 1988, Almond M&M's hit stores with limited release, with appearances only during Christmas and Easter times. These candies are much like the peanut variety, but with an almond instead of a peanut inside the candy. Due to rising popularity, Mars gave them full releases in 1992.

[edit] 1990s In 1990, Peanut Butter M&M's were released. These candies have peanut butter inside the chocolate center and the same color scheme as the other brands.

In 1993, Mars ran a promotion in which consumers were invited to vote on which of blue, pink, or purple would be introduced. Blue was the winner, replacing tan in early 1995. Consumers could vote by calling 1-800-FUN-COLOR

Around the same time, novelty M&M's were available in specialty stores, such as FAO Schwarz, in 21 different colors.

In 1996, Mars introduced a new M&M's candy: the "M&M's Minis". These candies are very small and are usually sold in small plastic tubes instead of bags. A video game, M&M's: The Lost Formulas, was also eventually released, based on this candy.

In 1998, Crispy M&M's were released. They were slightly larger than the milk chocolate variety and feature a crispy rice center. They were discontinued in the United States in 2005, but they are still available in Europe and southeast Asia.[9]

[edit] 2000–2005 In 2002, Mars solicited votes to add a new color from three choices. Once again, the general public were the voters. The choices were aqua, pink, and purple. This time, purple won.[10]

In June 2004, M&M's were mentioned in the media when Mike Melvill, who flew a weightless suborbital arc in SpaceShipOne, the world's first private piloted space flight, opened up a package of the chocolate brand when he reached the border of space (100km) in order to demonstrate weightlessness as the candy floated in the cabin. Melvill chose the candies because they were both colorful, therefore showing up well on camera, and because once gravity returned, if they fell into any of the controls they could be easily crushed and not interfere with the mechanisms. Melvill never told his bosses about his unauthorized stunt.

Also in 2004, My M&M's opened its web site doors (http://www.mymms.com). People could come to the site and have messages printed on M&M's with their choice of 2 colors. In the time since, they have expanded the site to handle many gifting options and business to business orders, allowing companies to upload logos to be printed.

In April 2005, M&M's ran the "mPire" promotion to tie in with the Star Wars Episode III: Revenge of the Sith movie release. M&M's were offered in a dark variety for the first time.

In the summer of 2005, Mars added "Mega M&M's" to the lineup.[11] These candies are 55% larger than the traditional M&M's and are available in milk chocolate and peanut varieties. Most of the colors for Mega M&M's were also changed to less-bright colors — teal (replacing green), beige (orange), maroon (red), gold (yellow), blue-gray (blue), and brown — to appeal more to adults. In the fall of 2005, the mPire promotion ran again to coincide with the DVD release of the Star Wars movie.

"My Color" Wall inside M&M's World Las Vegas Strip [edit] 2006–present In 2006, Mars offered eight new flavors of M&M's via online sales, as well as at M&M's World locations. The flavors are All That Razz; Eat, Drink, & Be Cherry; A Day at the Peach; Orange-U-Glad; Mint Condition; AlmonDeeLicious; Nut What You Think; and Cookie Minster. The first five have a white chocolate and milk chocolate center with a flavored shell. The two nut flavors have an almond or peanut center with white chocolate and candy shell. Cookie Minster has a crispy center with dark chocolate and a mint flavored shell. The company also released a Crispy Mint variety in Australia. Also in July 2006, Dark Chocolate M&M's reappeared in a purple package with the green female M&M as the mascot. In 2006, the company also piloted White Chocolate M&M's as a tie-in with their Pirates of the Caribbean promotion.

Beginning in 2005, M&M's can be purchased online in 17 colors, with personalized phrases on each candy on the opposite side from the "m".[12] Released around Christmas, these custom printed M&M's were originally intended for holiday greetings, but are now available year-round.

In 2007, M&M's introduced a new raspberry flavor chocolate candy that looks like the plain, but is fuchsia and slightly larger, called "M&M's Razzberry Chocolate Candies."

M&M's currently have recognizable "spokescandies" which appear in commercials: these include the team of the cynical and sardonic "Red" (originally Jon Lovitz, thereafter Billy West), who is the mascot for milk chocolate M&M's, and the happy and gullible "Yellow" (originally John Goodman, thereafter J.K. Simmons), who is the mascot for peanut M&M's. Other mascots include the "cool one", Blue (Robb Pruitt) for almond; Green (Cree Summer) for peanut butter, mint, and dark chocolate (the only female M&M's mascot); and Orange (Eric Kirchberger) for other types of M&M's in general, who was initially not named after his color (for a time when he was introduced, he was known as Crispy due to his being a mascot for the now discontinued Crispy M&M's, which debuted around the same time).

During the 2008 Valentine's Day season Mars introduced bags of all green M&M's. This was due to common urban folklore that holds green M&M's to be an aphrodisiac.[13]

In 2008, two new varieties of the candy were introduced — Wildly Cherry M&M's, and as a marketing tie-in with the film Indiana Jones and the Kingdom of the Crystal Skull, Mint Crisp M&M's.

M&M's also introduced another new product called "M&M's Premiums" in 2008. They come in five flavors — chocolate almond, mint chocolate, mocha, raspberry almond and triple chocolate (milk, dark, and white chocolate), which are sold in small upright cartons with a plastic bag inside. M&M's Premiums do not have a candy shell, but are coated with carnauba wax and color.

During summer of 2008, My M&M's launched 'Faces,' which allows consumers to print the faces of loved ones on M&M's chocolate candies

The Cocoa tree is native to the Americas. It may have originated in the foothills of the Andes in the Amazon and Orinoco basins of South America where today, examples of wild cacao still can be found. However, it may have had a larger range in the past, evidence for which may be obscured because of its cultivation in these areas long before, as well as after, the Spanish arrived. It may have been introduced into Central America by the ancient Mayas, and cultivated in Mexico by the Olmecs, then by the Toltecs and later by the Aztecs. It was a common currency throughout Mesoamerica and the Caribbean before the Spanish conquest.

Cacao trees will grow in a limited geographical zone, of approximately 20 degrees to the north and south of the Equator. Nearly 70% of the world crop is grown in West Africa.

Cocoa was an important commodity in Pre-Columbian Mesoamerica. Spanish chroniclers of the conquest of Mexico by Hernán Cortés relate that when Montezuma II, emperor of the Aztecs, dined he took no other beverage than chocolate, served in a golden goblet and eaten with a golden spoon. Flavored with vanilla and spices, his chocolate was whipped into a froth that dissolved in the mouth. It is reported that Montezuma II may have consumed no fewer than 50 portions each day, and 200 more by the nobles of his court.

Chocolate was introduced to Europe by the Spaniards and became a popular beverage by the mid 1600s.[4] They also introduced the cacao tree into the West Indies and the Philippines.

The cacao plant was first given its botanical name by Swedish natural scientist Carolus Linnaeus in his original classification of the plant kingdom, who called it Theobroma ("food of the gods") cacao.

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== Animal From Wikipedia, the free encyclopedia Jump to: navigation, search "Animalia" redirects here. For other uses, see Animalia (disambiguation). For other uses, see Animal (disambiguation). Animals Fossil range: Ediacaran or earlier - Recent

Clockwise from top-left: Loligo vulgaris (a mollusk), Chrysaora quinquecirrha (a cnidarian), Aphthona flava (an arthropod), Eunereis longissima (an annelid), and Panthera tigris (a chordate). Scientific classification Domain: Eukaryota (unranked): Opisthokonta Kingdom: Animalia Linnaeus, 1758 Phyla Subkingdom Parazoa Porifera Subkingdom Eumetazoa Placozoa Radiata (unranked) Ctenophora Cnidaria Bilateria (unranked) Orthonectida Rhombozoa Acoelomorpha Chaetognatha Superphylum Deuterostomia Chordata Hemichordata Echinodermata Xenoturbellida Vetulicolia † Protostomia (unranked) Superphylum Ecdysozoa Kinorhyncha Loricifera Priapulida Nematoda Nematomorpha Lobopodia † Onychophora Tardigrada Arthropoda Superphylum Platyzoa Platyhelminthes Gastrotricha Rotifera Acanthocephala Gnathostomulida Micrognathozoa Cycliophora Superphylum Lophotrochozoa Sipuncula Hyolitha † Nemertea Phoronida Bryozoa Entoprocta Brachiopoda Mollusca Annelida Echiura Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and independently. Animals are also heterotrophs, meaning they must ingest other organisms for sustenance.

Most known animal phyla appeared in the fossil record as marine species during the Cambrian explosion, about 542 million years ago.

Contents [hide] 1 Etymology 2 Characteristics 2.1 Structure 2.2 Reproduction and development 2.3 Food and energy sourcing 3 Origin and fossil record 4 Groups of animals 4.1 Deuterostomes 4.2 Ecdysozoa 4.3 Platyzoa 4.4 Lophotrochozoa 5 Model organisms 6 History of classification 7 See also 8 References 8.1 Notes 8.2 Bibliography 9 External links

Etymology The word "animal" comes from the Latin word animale, neuter of animalis, and is derived from anima, meaning vital breath or soul. In everyday colloquial usage, the word usually refers to non-human animals. The biological definition of the word refers to all members of the Kingdom Animalia, including humans.[1]

Characteristics Animals have several characteristics that set them apart from other living things. Animals are eukaryotic and usually multicellular[2] (although see Myxozoa), which separates them from bacteria and most protists. They are heterotrophic,[3] generally digesting food in an internal chamber, which separates them from plants and algae (some sponges are capable of photosynthesis and nitrogen fixation though).[4] They are also distinguished from plants, algae, and fungi by lacking cell walls.[5] All animals are motile,[6] if only at certain life stages. In most animals, embryos pass through a blastula stage, which is a characteristic exclusive to animals.

Structure With a few exceptions, most notably the sponges (Phylum Porifera) and Placozoa, animals have bodies differentiated into separate tissues. These include muscles, which are able to contract and control locomotion, and nerve tissue, which sends and processes signals. There is also typically an internal digestive chamber, with one or two openings. Animals with this sort of organization are called metazoans, or eumetazoans when the former is used for animals in general.

All animals have eukaryotic cells, surrounded by a characteristic extracellular matrix composed of collagen and elastic glycoproteins. This may be calcified to form structures like shells, bones, and spicules. During development it forms a relatively flexible framework upon which cells can move about and be reorganized, making complex structures possible. In contrast, other multicellular organisms like plants and fungi have cells held in place by cell walls, and so develop by progressive growth. Also, unique to animal cells are the following intercellular junctions: tight junctions, gap junctions, and desmosomes.

Reproduction and development A newt lung cell stained with fluorescent dyes undergoing mitosis, specifically early anaphase.Nearly all animals undergo some form of sexual reproduction. Adults are diploid or polyploid. They have a few specialized reproductive cells, which undergo meiosis to produce smaller motile spermatozoa or larger non-motile ova. These fuse to form zygotes, which develop into new individuals.

Many animals are also capable of asexual reproduction. This may take place through parthenogenesis, where fertile eggs are produced without mating, or in some cases through fragmentation.

A zygote initially develops into a hollow sphere, called a blastula, which undergoes rearrangement and differentiation. In sponges, blastula larvae swim to a new location and develop into a new sponge. In most other groups, the blastula undergoes more complicated rearrangement. It first invaginates to form a gastrula with a digestive chamber, and two separate germ layers - an external ectoderm and an internal endoderm. In most cases, a mesoderm also develops between them. These germ layers then differentiate to form tissues and organs.

Food and energy sourcing A juvenile Red-tailed Hawk eating a California VolePredation is a biological interaction where a predator (a heterotroph that is hunting) feeds on its prey (the organism that is attacked). Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of the prey. The other main category of consumption is detritivory, the consumption of dead organic matter. It can at times be difficult to separate the two feeding behaviours, for example where parasitic species prey on a host organism and then lay their eggs on it for their offspring to feed on its decaying corpse. Selective pressures imposed on one another has lead to an evolutionary arms race between prey and predator, resulting in various antipredator adaptations.

Most animals feed indirectly from the energy of sunlight. Plants use this energy to convert sunlight into simple sugars using a process known as photosynthesis. Starting with the molecules carbon dioxide (CO2) and water (H2O), photosynthesis converts the energy of sunlight into chemical energy stored in the bonds of glucose (C6H12O6) and releases oxygen (O2). These sugars are then used as the building blocks which allow the plant to grow. When animals eat these plants (or eat other animals which have eaten plants), the sugars produced by the plant are used by the animal. They are either used directly to help the animal grow, or broken down, releasing stored solar energy, and giving the animal the energy required for motion. This process is known as glycolysis.

Animals who live close to hydrothermal vents and cold seeps on the ocean floor are not dependent on the energy of sunlight. Instead, chemosynthetic archaea and bacteria form the base of the food chain.

Origin and fossil record Further information: Urmetazoon Dunkleosteus was a gigantic, 10 meter (33 ft) long prehistoric fish.[7] Vernanimalcula guizhouena is a fossil believed by some to represent the earliest known member of the Bilateria.Animals are generally considered to have evolved from a flagellated eukaryote. Their closest known living relatives are the choanoflagellates, collared flagellates that have a morphology similar to the choanocytes of certain sponges. Molecular studies place animals in a supergroup called the opisthokonts, which also include the choanoflagellates, fungi and a few small parasitic protists. The name comes from the posterior location of the flagellum in motile cells, such as most animal spermatozoa, whereas other eukaryotes tend to have anterior flagella.

The first fossils that might represent animals appear towards the end of the Precambrian, around 610 million years ago, and are known as the Ediacaran or Vendian biota. These are difficult to relate to later fossils, however. Some may represent precursors of modern phyla, but they may be separate groups, and it is possible they are not really animals at all. Aside from them, most known animal phyla make a more or less simultaneous appearance during the Cambrian period, about 542 million years ago. It is still disputed whether this event, called the Cambrian explosion, represents a rapid divergence between different groups or a change in conditions that made fossilization possible. However some paleontologists and geologists would suggest that animals appeared much earlier than previously thought, possibly even as early as 1 billion years ago. Trace fossils such as tracks and burrows found in Tonian era indicate the presence of triploblastic worm like metazoans roughly as large (about 5 mm wide) and complex as earthworms.[8] In addition during the beginning of the Tonian period around 1 billion years ago (roughly the same time that the trace fossils previously discussed in this article date back to) there was a decrease in Stromatolite diversity which may indicate the appearance of grazing animals during this time as Stromatolites also increased in diversity shortly after the end-Ordovician and end-Permian rendered large amounts of grazing marine animals extinct and decreased shortly after their populations recovered. The discovery that tracks very similar to these early trace fossils are produced today by the giant single-celled protist Gromia sphaerica casts further doubt on their interpretation as evidence of early animal evolution.[9][10]

Groups of animals Orange elephant ear sponge, Agelas clathrodes, in foreground. Two corals in the background: a sea fan, Iciligorgia schrammi, and a sea rod, Plexaurella nutans.The sponges (Porifera) were long thought to have diverged from other animals early. As mentioned above, they lack the complex organization found in most other phyla. Their cells are differentiated, but in most cases not organized into distinct tissues. Sponges are sessile and typically feed by drawing in water through pores. Archaeocyatha, which have fused skeletons, may represent sponges or a separate phylum. However, a phylogenomic study in 2008 of 150 genes in 21 genera[11] revealed that it is the Ctenophora or comb jellies which are the basal lineage of animals, at least among those 21 phyla. The authors speculate that sponges—or at least those lines of sponges they investigated—are not so primitive, but may instead be secondarily simplified.

Among the other phyla, the Ctenophora and the Cnidaria, which includes sea anemones, corals, and jellyfish, are radially symmetric and have digestive chambers with a single opening, which serves as both the mouth and the anus. Both have distinct tissues, but they are not organized into organs. There are only two main germ layers, the ectoderm and endoderm, with only scattered cells between them. As such, these animals are sometimes called diploblastic. The tiny Placozoans are similar, but they do not have a permanent digestive chamber.

The remaining animals form a monophyletic group called the Bilateria. For the most part, they are bilaterally symmetric, and often have a specialized head with feeding and sensory organs. The body is triploblastic, i.e. all three germ layers are well-developed, and tissues form distinct organs. The digestive chamber has two openings, a mouth and an anus, and there is also an internal body cavity called a coelom or pseudocoelom. There are exceptions to each of these characteristics, however - for instance adult echinoderms are radially symmetric, and certain parasitic worms have extremely simplified body structures.

Genetic studies have considerably changed our understanding of the relationships within the Bilateria. Most appear to belong to two major lineages: the Deuterostomes and Protostomes, which includes the Ecdysozoa, Platyzoa, and Lophotrochozoa. In addition, there are a few small groups of bilaterians with relatively similar structure that appear to have diverged before these major groups. These include the Acoelomorpha, Rhombozoa, and Orthonectida. The Myxozoa, single-celled parasites that were originally considered Protozoa, are now believed to have developed from the Bilateria as well.

Deuterostomes Superb Fairy-wren, Malurus cyaneusDeuterostomes differ from the other Bilateria, called protostomes, in several ways. In both cases there is a complete digestive tract. However, in protostomes the initial opening (the archenteron) develops into the mouth, and an anus forms separately. In deuterostomes this is reversed. In most protostomes, cells simply fill in the interior of the gastrula to form the mesoderm, called schizocoelous development, but in deuterostomes it forms through invagination of the endoderm, called enterocoelic pouching. Deuterostomes also have a dorsal, rather than a ventral, nerve chord and their embryos undergo different cleavage.

All this suggests the deuterostomes and protostomes are separate, monophyletic lineages. The main phyla of deuterostomes are the Echinodermata and Chordata. The former are radially symmetric and exclusively marine, such as starfish, sea urchins, and sea cucumbers. The latter are dominated by the vertebrates, animals with backbones. These include fish, amphibians, reptiles, birds, and mammals.

In addition to these, the deuterostomes also include the Hemichordata or acorn worms. Although they are not especially prominent today, the important fossil graptolites may belong to this group.

The Chaetognatha or arrow worms may also be deuterostomes, but more recent studies suggest protostome affinities.

Ecdysozoa Yellow-winged darter, Sympetrum flaveolumThe Ecdysozoa are protostomes, named after the common trait of growth by moulting or ecdysis. The largest animal phylum belongs here, the Arthropoda, including insects, spiders, crabs, and their kin. All these organisms have a body divided into repeating segments, typically with paired appendages. Two smaller phyla, the Onychophora and Tardigrada, are close relatives of the arthropods and share these traits.

The ecdysozoans also include the Nematoda or roundworms, the second largest animal phylum. Roundworms are typically microscopic, and occur in nearly every environment where there is water. A number are important parasites. Smaller phyla related to them are the Nematomorpha or horsehair worms, and the Kinorhyncha, Priapulida, and Loricifera. These groups have a reduced coelom, called a pseudocoelom.

The remaining two groups of protostomes are sometimes grouped together as the Spiralia, since in both embryos develop with spiral cleavage.

Platyzoa Bedford's flatworm, Pseudobiceros bedfordiThe Platyzoa include the phylum Platyhelminthes, the flatworms. These were originally considered some of the most primitive Bilateria, but it now appears they developed from more complex ancestors.[12]

A number of parasites are included in this group, such as the flukes and tapeworms. Flatworms are acoelomates, lacking a body cavity, as are their closest relatives, the microscopic Gastrotricha.[13]

The other platyzoan phyla are mostly microscopic and pseudocoelomate. The most prominent are the Rotifera or rotifers, which are common in aqueous environments. They also include the Acanthocephala or spiny-headed worms, the Gnathostomulida, Micrognathozoa, and possibly the Cycliophora.[14] These groups share the presence of complex jaws, from which they are called the Gnathifera.

Lophotrochozoa Roman snail, Helix pomatiaThe Lophotrochozoa include two of the most successful animal phyla, the Mollusca and Annelida.[15][16] The former, which is the second-largest animal phylum, includes animals such as snails, clams, and squids, and the latter comprises the segmented worms, such as earthworms and leeches. These two groups have long been considered close relatives because of the common presence of trochophore larvae, but the annelids were considered closer to the arthropods,[17] because they are both segmented. Now this is generally considered convergent evolution, owing to many morphological and genetic differences between the two phyla.[18]

The Lophotrochozoa also include the Nemertea or ribbon worms, the Sipuncula, and several phyla that have a fan of cilia around the mouth, called a lophophore.[19] These were traditionally grouped together as the lophophorates.[20] but it now appears they are paraphyletic,[21] some closer to the Nemertea and some to the Mollusca and Annelida.[22][23] They include the Brachiopoda or lamp shells, which are prominent in the fossil record, the Entoprocta, the Phoronida, and possibly the Bryozoa or moss animals.[24]

Model organisms Main articles: Model organism and Animal testing Because of the great diversity found in animals, it is more economical for scientists to study a small number of chosen species so that connections can be drawn from their work and conclusions extrapolated about how animals function in general. Because they are easy to keep and breed, the fruit fly Drosophila melanogaster and the nematode Caenorhabditis elegans have long been the most intensively studied metazoan model organisms, and were among the first lifeforms to be genetically sequenced. This was facilitated by the severely reduced state of their genomes, but the double-edged sword here is that with many genes, introns and linkages lost, these ecdysozoans can teach us little about the origins of animals in general. The extent of this type of evolution within the superphylum will be revealed by the crustacean, annelid, and molluscan genome projects currently in progress. Analysis of the starlet sea anemone genome has emphasised the importance of sponges, placozoans, and choanoflagellates, also being sequenced, in explaining the arrival of 1500 ancestral genes unique to the Eumetazoa.[25]

An analysis of the homoscleromorph sponge Oscarella carmela also suggests that the last common ancestor of sponges and the eumetazoan animals was more complex than previously assumed.[26]

Other model organisms belonging to the animal kingdom include the mouse (Mus musculus) and zebrafish (Danio rerio}.

Carolus Linnaeus known as the father of modern taxonomy History of classification Aristotle divided the living world between animals and plants, and this was followed by Carolus Linnaeus (Carl von Linné), in the first hierarchical classification. Since then biologists have begun emphasizing evolutionary relationships, and so these groups have been restricted somewhat. For instance, microscopic protozoa were originally considered animals because they move, but are now treated separately.

In Linnaeus's original scheme, the animals were one of three kingdoms, divided into the classes of Vermes, Insecta, Pisces, Amphibia, Aves, and Mammalia. Since then the last four have all been subsumed into a single phylum, the Chordata, whereas the various other forms have been separated out. The above lists represent our current understanding of the group, though there is some variation from source to source