It has become an increasingly popular trend to attack the antiquated notion of an early Paleoindian specialized subsistence commitment to the predation of Pleistocene megafauna. In conforming to this trend, Cannon and Meltzer assert that the North American archaeofaunal record provides little support for the notion that Early hunter-gatherers practiced a continent-wide specialized subsistence pattern focused exclusively on large mammals. Instead, their 2008 article, Explaining Variability in Early Paleoindian Foraging, promotes evidence for regional variability in hunter-gatherer subsistence during the terminal Pleistocene of North America as a repercussion of geographic and environmental variability and its effect on a patch choice foraging model.
Their first swing at toppling the age-old paradigm of continent-wide uniformity in Paleoindian subsistence is armed with zooarchaeological evidence drawn from a previous study by Grayson and Meltzer (2002). This study provided a critical evaluation of the Early Paleoindian archaeofaunal record by analyzing the evidence for human predation on a variety of Pleistocene mammalian taxa. They concluded that of the approximately 35 genera of mammals that went extinct at the onset of the Holocene, a mere two (mammoth and mastodon) bore evidence for substantial human predation. In light of this, it must be recognized that not only is a megafauna specialization exaggerated, it must dually be noted that a uniform Paleoindian cross-continental foraging pattern is highly unlikely given that sites with strong evidence for predation upon proboscidians occur in the South west, the Plains and the Midwest, while bison occur at lower latitudes and caribou dominate the Northeast. Cannon and Meltzer offer this example of regional variability to substantiate their motive, but deviate to focus on more general variables pertaining to dietary diversity.
The variability in diet breadth and the degree to which Paleoindian hunters relied upon megafauna is tested in an analysis of 22 Early Paleoindian faunal assemblages with clear evidence for human predation on mammalian taxa. Regional variability in diet breadth is defined by “the number of mammalian genera per assemblage for which there is compelling evidence of subsistence use” (P.7).
This definition of variability based on the presence or absence of mammalian herbivores to the exclusion of smaller prey and plant based resources emphasizes a slanted perspective of Early Paleoindian subsistence. A focus on such a narrow portion of the dietary breadth may, understandably, be a result of sampling, site function and taphonomic or preservation biases, but fostering a constrained view without discretion hampers a truly holistic view of Early Paleoindian subsistence practices.
The 22 sites containing compelling evidence for human predation on mammalian taxa are designated to one of three physiogeographic regions dividing the continent, which are defined in reference to the central Great Plains.
As Cannon and Meltzer knowingly admit, this scale for ascertaining Early Paleoindian foraging variability, although somewhat unavoidable given the paucity for pertinent sites, neglects the microenvironments existing at much finer geographical scales within the three delineated regions. By neglecting the microenviornments of significant geographic zones, such as the Great Basin and the Rockies, the variability of the individual human economic adaptations to these environments are ignored, overshadowed by the artificially amplified patterns stemming from the chosen regional boundaries.
A comparison of the 22 site’s zooarchaeological assemblage richness defined by the number of large-bodied taxa affirmed some intra-regional variability in Paleoindian diet breadth. A general East-West trend for increasing richness was detected. In addition to these predicted regional differences, a significant dominance of megafauna was detected, especially in the Central Plains and to the West where assemblages were dominated almost exclusively by large-bodied herbivores. The Eastern samples supported a slightly higher species diversity, yet with a reduced emphasis on the presence of megafauna. Cannon and Meltzer summarize their study by stating that “once sampling and taphonomic biases are taken into account, Early Paleoindian diets across the continent were more generalized than the received wisdom would have us believe” (P.11). Their findings indicate variability in Paleoindian subsistence included not only variability in the breadth of exploited mammalian taxa, but also to the degree to which megafauna were exploited.
Having established subsistence variability to be intrinsic to Early Paleoindian populations existing in the terminal Pleistocene, Cannon and Meltzer turn to address the question, “can we explain this regional variability in subsistence?” (P.11).
Cannon Meltzer employ the “fractal patch choice” model used to “develop predictions about the proportion of resource patches within an environment that a forager should use- that is, whether a forager should be a ‘patch specialist’ or a ‘patch generalist’- based on the ‘grain size’ of the environment, or the degree of spatial heterogeneity that it exhibits” (P.11). This model can be calibrated to make predictions about landscape use based on environmental characteristics of the terminal Pleistocene. Available data suggests that North American environments varied in a manner favoring a generalist approach more so in the East than in the Plains or the West based on vegetation heterogeneity. This conclusion, derived from the patch-choice model as applied to the inferred grain size of North American environments during the terminal Pleistocene, affirms that the structure of those environments can account for the variability in prey choice evident in the 22 Early Paleoindian faunal assemblages.
The existing archaeofaunal and paleoenvironmental records are an excellent validation of the fractal patch choice model as demonstrated by Canon and Meltzer. It is consistent with the notion that Paleoindian subsistence strategies varied in response to the heterogeneity of the environment. However, should the explanatory potential of the fractal patch choice model be developed enough to extend beyond strictly the size of patches and to incorporate the content of patches, the explanatory scope would be significantly enlarged.
Cannon, Michael D. Cannon, David J. Meltzer
2008 Explaining Variability in Early Paleoindian foraging. Quaternary International 2008(191): 5-17.
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