User talk:Patmgreen

Hi Patrick. I haven't been able to find your Wikipedia article. Can you tell me how to access it? --Hoopes (talk) 14:58, 6 October 2009 (UTC)

My apologies, I assumed you were to look over a word file and edit it before we posted it on wikipedia (like in the Theory class). I sent a word file the day it was due, but here it is.

Isthmo-Columbian Paleoindians

Introduction
Paleoindians are the first archaeologically identified peoples in the Americas. Pan-continental in presence, they share traits such as hunting/foraging subsistence, a predominantly lithic toolkit, and time span (~13,000-8,500 years BP) but have a degree of regional differentiation, especially more recently in time. Paleoindian-age discoveries in Isthmo-Colombian America are sparser than in North America but inform archaeologists of the lifeways, migration patterns, and environmental adaptations of the earliest New World inhabitants. This area offers a compelling research opportunity given its diverse amount of ecosystems within a small landmass and the isthmus’ funneling effect on populations.

Migration Theories
Leading theories of the peopling of the Isthmo-Colombian area are tied into those of the whole of the Americas. These include migration across a late Ice Age landbridge connecting NW America and NE Asia (Beringia) followed by rapid dispersal across the continents, a sea route following the west coast of the U.S. with stopping points along the whole of the Americas, and a European-origin sea route following the more glaciated northern Atlantic during the end of the last Ice Age (the Solutrean hypothesis).

Solutrean Hypothesis
Isthmo-Colombian Paleoindian-aged discoveries both support and question these theories. The European origin theory focuses on the similarity between the lithic technology of the predominant Paleoindian archaeological culture, Clovis, and the European Upper European Solutrean culture. Both toolkits feature large, leaf-shaped bifacially flaked projectile points that were used to hunt the favored megafauna prey of terminal Pleistocene peoples. Clovis-style points have been found throughout Central America (albeit often in poor context) but similarly aged projectile point styles such as El Jobo and fishtail points are found in similar Paleoindian contexts with the latter occasionally in the same association as Clovis. This temporal and spatial association, coupled with the unlikelihood of survival of a North Atlantic route and lithic specialist support for the dissimilarity of technique between Soultrean and Clovis implements, have made this theory questionable.

Overland via Beringia Route
The overland route with origin at Beringia model has long been the standard American peopling model, but modern discoveries in Central America and further south have questioned some of its claims. Designating northwestern-most America as the entrance point implies that it should have America’s oldest archaeological sites. However, the majority of the Paleoindian-aged sites in this region, representing the Arctic microblade tradition, come later than those much further South such as Guardiria in Costa Rica (10-12,000 years BP). Though Central America contains many Clovis-like points, it is also home to Clovis-contemporaneous (and perhaps older) El Jobo and fishtail point industries. The diversity in point styles implies the region as a homeland for American lithic industries following evolutionary principles, with Clovis as derivative of a more ancient industry. Additionally, the El Jobo points in Colombia and Venezuela are likely older (~13,000 years BP) than Clovis and have few similarities in form and production method.

Pacific Coast Route
Seacraft evidence of Paleoindian age is not abundant, but such vessels were in use due to hints from the archaeological record. The Channel Islands near California contain shell midden and chert workshop sites dating to 12-11,500 years BP and the earliest dated fish hooks at ~10.5 YBP. While no Central American correlate exists, the Channel Island findings assert Paleoindian capability to sail and desire to exploit marine resources. Sailing is the most parsimonious method of travel that supports the near and archaeologically sudden simultaneous population throughout the Americas. Unfortunately, sea level has risen considerably since the late Pleistocene, causing the loss of potential sites along the present continental shelf that were once ashore. Central America had considerable landmass lost to sea level rise, including much off the eastern coasts of Nicaragua and Honduras that nearly extended to the Antilles.

Linguistic and Genetic Contributions
In addition to archaeological sites, biological indicators and language evolutionary history of modern day natives have been used to infer initial migration and subsequent expansion. Morphological studies like Greenberg et. al’s 1986 and Turner and Scott’s 2007 studies of Native dentition evolution and some genetic-based  conclude that the lack of diversity in morphological traits of pan-Native American teeth (e.g., shovel-shaped incisors and one root in the first upper premolar) and key genetic markers (non-recombining portions of the Y chromosome, or NRY, and mitochondrial DNA, or mtDNA) signify all Native American populations are evolutionarily young and descendent of a single population. While these studies support much of the “Clovis First” thinking, studies examining similar locations on the genome have concluded the opposite: multiple waves of initial migration, signifying multiple founding Paleoindian populations of modern New World natives, and/or very ancient initial arrival(s) far predating Clovis. While different methodological approaches could explain the varying results, factors such as underestimation of the rates of genetic change or overestimation of population variance can explain the disparity of results. Central American genetic evidence contributes to the debate through association with language evolution to help infer ancient migrations. A majority of Isthmo-Colombian natives are speakers of the Chibchan language family. This family has been targeted in migration studies due to its well-defined location along the “hub” that is Central America between the two continents and the relative genetic homogeneity, or lack of admixture, of its speakers. Using mtDNA and Y-chromosome markers, the ancestors of modern-day Chibchan speakers diverged from the earliest Central American populations by 10-8,500 years ago and had subsequent isolation from other groups. This isolation was associated with large scale climate change. More recently in time, ancient Chibchan speakers spread across the isthmus coupled with the spread of agriculture, and then later maintained much of their integrity after contact with ancient Mesoamericans and European colonists. This population and its descendants have had geographic and relative genetic stability in Central America since Paleoindian times.

Isthmo-Colombian Paleoindian Archaeology
Generally, most Isthmo-Columbian Paleoindian sites are scatters of the byproducts of toolmaking with the occasional diagnostic tool in largely undatable contexts. Tools discovered share similarities to their North American correlates (largely cryptocrystalline raw material, large game adapted) but lack formalized flaking and lithic procurement strategies on the scale of Clovis. Subsistence was diverse given the location of sites within all major physiographic regions, though desire for the presumed preferred habitat of Clovis-like big game hunters (open grassland) is evident in increased charcoal and charred phytoliths near many lakes likely representative of forest burning/clearing. Evidence of culture and belief systems is exceedingly rare throughout the Americas. No correlate of mobile art such as the carved Tequixquiac camelid sacrum or use of red ochre has yet to be found in Isthmo-Colombian Paleoindian context.

Taima Taima
Taima Taima, located near the Carribean coast in the Falcón state of Venezuela, is a terminal Pleistocene megafauna kill site with associated hunting and butchering artifacts. Several El Jobo points and expediently made tools such as scrapers were found with mastodon bones that featured evidence of tool use wear. These discoveries correlated well with North American Paleoindian finds during the time of excavation in the mid-1970’s, but the site’s absolute dating did not. A radiocarbon age of 13,000 years BP, along with questions of site integrity, didn’t correlate with the then-dominant “Clovis First” model which postulated 11,000 years BP initial entry to both the Americas. The proposed antiquity of the site was largely ignored until the discovery of many other pre-Clovis sites. The site’s and El Jobo’s relation to Clovis, such as whether El Jobo was descendant or ancestor to Clovis is under current examination (Pearson 2002).

Guardiria
Guardiria, located on the river terraces of the Turrialba valley in central Costa Rica is the largest Paleoindian site in the Americas. It contains over 28,000 lithic artifacts including three styles of projectile points: fishtail, parallel sided and waisted. Lithic reduction is comparable to Clovis techniques, especially in the parallel sided and waisted points, but the site features more end product diversity than a typical Clovis site including the non-projectile tools. The finds have been dated to 10-12,000 years BP, but modern plowing has destroyed much of the stratigraphic archaeological context, with modern inclusions along ancient points. Its location along a major river system served as excellent campsites and raw lithic material sources from the river cobbles.