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The Fremont provide an important case study to examine the resilience of ancient farmers to climatic downturns, because they lived at the far northern margin of intensive maize agriculture in the American West, where the constraints on maize production are made abundantly clear. Using a tree-ring and simulation-based reconstruction of average annual precipitation and maize growing degree days, along with cost-distance to perennial streams, we model spatial variability in Fremont site density in the eastern Great Basin. The results of our analysis have implications for defining the ecological envelope in which farming is a viable strategy across this arid region and can be used to predict where and why maize farming strategies might evolve and eventually collapse as climate changes over time. [ABSTRACT FROM AUTHOR]

In this paper, we explore and integrate different currencies that may underlie large-game hunting to guide a trans-Holocene analysis of variation in artiodactyl utilization using massive archaeofaunal data-sets from predominantly open-air sites from the Bonneville and Wyoming basins. The available empirical data continue to suggest that artiodactyls yield consistently higher return rates than lagomorphs allowing us to leverage predictions from both the prey choice and energetic risk-gain models that the relative importance of artiodactyl hunting should scale closely with climate-based change in their abundance on the landscape. We document with modeled climate data that seasonal variables correlated with the relative frequency of artiodactyl hunting, but that summer temperature had a significant overriding effect in both regions. Controlling for the negative relationship between summer temperature and artiodactyl abundances, we then document enhanced artiodactyl hunting in general and bison more specifically during the Fremont period that is consistent with a costly signaling hypothesis and the unique socio-ecological conditions of this context. Thus, climatic variation and its influence on artiodactyl abundances drives the overall trajectory of Holocene large game hunting variation but measurable and more subtle influences of costly signaling are also detected. [ABSTRACT FROM AUTHOR]

At the end of the Pleistocene as temperatures warmed, new habitats opened up to human occupation as the Fennoscandian Ice Sheet receded. Along the west coast of modern-day Norway, human populations of coastal foragers slowly transitioned from short-term settlement patterns in the Early Mesolithic (ca. 11,500–10,000 cal BP), to more lasting ones during the Late Mesolithic (8500-6000 BP) and Early Neolithic (ca. 6000–5200 BP) as climatic conditions improved and stabilized. Here, using spatially and temporally resolved archaeological observations, paleoclimate data, and a spatiotemporal species distribution model, we test whether a) improvements in climate resulted in expansion of the available human niche space allowing for human population growth, and b) whether increasing population densities and ensuing deprecation of habitat suitability pushed people into occupying successively lower ranked habitats as predicted by the Ideal Free Distribution model. We find that a) climate gradually improved and stabilized during the Holocene, with the effect of improving general habitat suitability, which in turn led to an increase in human population size, b) that immediate proximity to sheltered coastal areas was central to settlement decisions but that c) increasing populations did not drive dispersal patterns into lower ranked habitats. The latter is likely attributable to the general improvements in habitat suitability due to the warming climate and the relative abundance of coastal habitats found in Norway. [ABSTRACT FROM AUTHOR]

The spread of agriculture is a major driver of social and environmental change throughout the Holocene, yet experimental and ethnographic data indicate that farming is less profitable than foraging, so why would individuals choose to adopt agriculture leading to its expansion? Ideal distribution models offer one framework to answer this question: Individuals should adopt less profitable subsistence strategies and occupy more marginal environments when local population density increases competition to the point where the suitability of the best strategies and habitats becomes equal to what can be gained in poorer strategies and habitats. Coupling radiocarbon-dated archaeological sites with a validated measure of agricultural suitability, we evaluate the emergence of farming in the Basin-Plateau region of North America. Our results show that farming first occurs in the more suitable Colorado Plateau physiographic region, and only spreads into the less suitable Great Basin after population density on the Plateau increases. This produces an approximate 300- to 400-year lag between the onset of farming on the Plateau and in the Basin. These findings support the ideal distribution hypothesis for the spread of farming, and suggest a general socioecological process that may help explain global patterns in the timing and tempo of agricultural expansions. [ABSTRACT FROM AUTHOR]

How might subsistence strategies structure the costs and benefits of habitat selection and, therefore, drive settlement patterning? We explore this question within an Ideal Distribution framework, arguing that (i) a habitat can be decomposed into its environmental covariates, (ii) their relative contributions to suitability can vary as a function of subsistence strategy, and (iii) the resulting differences will in turn lead to different population distributions across habitats. To evaluate these claims, we apply a Poisson point-process modelling approach known as maximum entropy (MaxEnt) to Archaic hunter-gatherer and Formative maize-farmer sites within the Grand Staircase-Escalante National Monument. Our results show that environmental covariates vary in their importance for each strategy and that the strategies themselves vary in their land use and habitat distribution, with Archaic foragers being widely distributed across space, Formative farmers more densely packed into areas indicative of higher maize productivity. The approach itself also has wide application to other subsistence strategies, including horticulture and pastoralism, across a range of environmental conditions. [ABSTRACT FROM AUTHOR]