Holocene artiodactyl population histories and large game hunting in the Wyoming Basin, USA

Abstract

Regional paleoenvironmental reconstructions and data on artiodactyl response to climate change suggest that large game densities would have expanded during the late Holocene in the Wyoming Basin. Within this context, we use the prey model of foraging theory to predict a late Holocene increase in the hunting of artiodactyls, relative to lagomorphs and rodents. This prediction is then tested against 144 dated components documenting human subsistence in the Wyoming Basin. Close fits are found between the deductively derived prediction and the empirical records: significant increases in artiodactyl hunting occurred during the late Holocene. These results have implications for the interpretation of long-term increases in large-game in Holocene archaeofaunas throughout North America.

Introduction

Archaeological investigations in the oil and gas fields of the Wyoming Basin (Fig. 1) have produced an extensive dataset documenting at least 9500 years of hunter–gatherer subsistence and settlement patterns. This region thus provides an ideal laboratory for testing hypotheses about the relationship between long-term environmental change and hunter–gatherer lifeways. Indeed, given the extent of the survey and excavation conducted in the Wyoming Basin, the area may well be one of the more extensively documented prehistoric hunter–gatherer contexts anywhere in the world. Relative to the intensity of field research however, there are few published studies incorporating the vast Wyoming Basin archaeological record into a synthetic and theoretically driven framework designed to explain patterns of human adaptation [but see [75], [76], [82], [83], [129], [130], [133], [132]. To begin filling this gap, we integrate the Wyoming Basin archaeofaunal record with data on artiodactyl ecology and regional paleoenvironmental information to document the relationship between climate, artiodactyl population histories and human hunting strategies in the region over the past 10,000 years.

The paleoenvironmental data we summarize suggest that precipitation varied substantially during the Holocene in the Wyoming Basin [18], [33], [104]. Since artiodactyl reproduction responds positively to long-term increases in precipitation [13], [30], [116], [151], the regional moisture history can be used to model large-scale variation in artiodactyl abundances. These trans-Holocene patterns in the natural abundances of artiodactyls are used to leverage predictions from the prey model [137] regarding the proportionate hunting of large and small game. We then test these predictions with a rich archaeofaunal database from the Wyoming Basin. As in other areas of western North America, the Wyoming Basin experienced a dramatic ascendance of large game hunting during the late Holocene. Like the well-documented pattern in the Great Basin [19], a climate-driven increase in artiodactyl densities appears responsible for the proportionate increase in large game hunting during the late Holocene in the Wyoming Basin.