Ideal free settlement of California’s Northern Channel Islands

Abstract

a b s t r a c tThe prehistoric establishment and expansion of permanent settlements on the Northern Channel Islands of southern California generally follows a pattern predicted by the population ecology model, the ideal free distribution (IFD). We determine this by comparing the abundant archaeological record of these Islands against a careful quantification of habitat suitability using areal photography, satellite imagery, and field studies. We assess watershed area, length of rocky intertidal zone, length of sandy beach for plank canoe pull-outs and area of off-shore kelp beds, for 46 coastal locations. A simple descriptive analysis supports key IFD predictions. A Bayesian model fitted with the Gibbs sampler allows us to reconstruct the Native assessment of habitat that appears to underlie this process. Use of the Gibbs sampler mitigates the impact of missing data, censored variables, and uncertainty in radiocarbon dates; it allows us to predict where new settlements may yet be discovered. Theoretically, our results support a behavioral ecology interpretation of settlement history, human population expansion, and economic intensification in this region. They also demonstrate Bayesian analytical methods capable of making full use of the information available in archaeological datasets.Ó 2010 Elsevier Inc. All rights reserved. Introduction and problemThe Native Americans who moved from the mainland to settle the Northern Channel Islands of southern California knew well the country they were settling. By first recorded permanent settlement ($8000-7000 cal. years BP) they had been exploring and seasonally exploiting the resources of the islands for as much as 5000 years Kennett, 2005;. Subsequent to that first settlement further Island colonization of coastal sites at the mouths of major drainages drew on local knowledge gained through even more lengthy experience. Settlers were familiar with the suitability of the habitats they were about to occupy and, we might predict, they established residential sites in an orderly process of adaptive decision-making: Settle first in the most salubrious location. When, with growing exploitation or crowding, its resources were depressed and its value declined to match the next-ranked locale, establish a new settlement there. As population grew this process repeated, adding further new settlements in locations ordered by habitat suitability. In parallel, we expect overall quality of life in all occupied locales declined due to reductions in the availability of or access to critical resources. This process is neatly captured in a behavioral ecology model: the ideal free distribution (IFD, Fretwell and Lucas, 1969). Analysis of environmental and archaeological data from the Northern Channel Islands indicates that colonization there follows IFD predictions. To demonstrate this, we first describe the prehistory of the Northern Channel Islands. We then introduce the IFD, with the goal of predicting how population growth, intensified use and declining suitability generate a predictab...

Large mammal biomass predicts the changing distribution of hunter-gatherer settlements in mid-late Holocene Alaska

“…Archaeologists routinely recognize relationships among resource distribution, adaptive strategies, and prehistoric settlement patterns (Bettinger and Baumhoff, 1982;Binford, 1980;Jochim, 1991;Winterhalder et al, 2010). Many have drawn on environmental and ecological variables to reconstruct settlement and subsistence patterns for prehistoric cultures of Alaska (Clark, 1984;Dumond, 1987a;Mason and Gerlach, 1995;Potter, 2008a;Yesner, 1981) and archaeological traditions have been linked to particular habitats (e.g., Dixon, 2013;Dumond, 1987b;Esdale, 2008).…”

“…Developed first to describe the dispersive behavior and distribution of birds (Fretwell and Lucas, 1969), the IFD has recently proved useful for explaining anthropological problems as well (Codding and Jones, 2013;Jazwa et al, 2013;Kennett et al, 2006;O'Connell and Codding, 2014;Winterhalder et al, 2010). The model posits that dispersive organisms will choose to locate first in the most suitable habitat available.…”

Ideal Free Distributions of Mobile Pastoralists in Multiple Seasonal Grazing Areas

“…The concept of the IFD has been used in behavioral ecology studies to examine habitat selection and foraging strategies of animals (Kennedy and Gray 1993;Sutherland 1996;Hamilton 2010), but recently it has also been used to study the mobility and settlement patterns of human populations (Kennett et al 2006;Winterhalder et al 2010), including mobile pastoralists (Scholte et al 2006;Behnke et al 2008Behnke et al , 2011. Pastoral systems provide an excellent case for examining IFD theory because the mobility and settlement patterns of pastoralists are primarily driven by spatiotemporal changes in the distribution of forage and water, even though the human dimension of pastoral systems means that nonforage constraints shape mobility and settlement patterns (Behnke et al 2011).…”

Environmental productivity predicts migration, demographic, and linguistic patterns in prehistoric California

“…S2). Recent anthropological applications of the IFD have proven useful for explaining patterning in prehistoric colonization and settlement (14)(15)(16)(17)(18). The basic model assumes that environments vary in their suitability and that habitats decline in suitability as a function of population density.…”