A Test of Ideal Free Distribution Predictions Using Targeted Survey and Excavation on California’s Northern Channel Islands

Abstract

Using targeted survey, excavation, and radiocarbon dating, we assess the extent to which human settlement patterns on California's northern Channel Islands fit predictions arising from the ideal free distribution (IFD): (1) people first established and expanded permanent settlements in the regions ranked high for environmental resource suitability; (2) as population grew, they settled in progressively lower ranked habitats; and (3) changes in the archaeological record associated with high population levels such as increases in faunal diversity and evenness in high-ranked habitats are coincident with the expansion to other areas. On Santa Rosa Island, the early permanent settlements were located in both high-and middle-ranked locations, with the most extensive settlement at the highest ranked locations and only isolated sites elsewhere. Settlement at a low-ranked habitat was confined to the late Holocene (after 3600 cal BP). Drought influenced the relative rank of different locations, which is an example of climate adding a temporal dimension to the model that episodically stimulated population movement and habitat abandonment. Because the IFD includes a wide range of cultural and environmental variables, it has the potential to be a central model for guiding archaeological analysis and targeted field research.

Geospatial modelling for predicting the ideal free settlement of Rapa

“…The application in this paper is island specific, similar to application in the Northern Channel Islands (Jazwa et al . ; Winterhalder et al . ).…”

“…Most archaeological applications of the IFD have been more broadly focused on a regional scale (Giovas & Fitzpatrick 2014;Kennett et al 2006b). The application in this paper is island specific, similar to application in the Northern Channel Islands (Jazwa et al 2015;Winterhalder et al 2010). Unlike these latter models, the IFD logic is not meant to describe initial colonisation of different parts of the island, but instead to describe a process of habitat infilling for the post-colonisation expansion of intensified irrigated agriculture.…”

“…The IFD has been used to understand island colonisation from the Caribbean (Giovas & Fitzpatrick 2014), the Northern Channel Islands (Jazwa et al 2015;Winterhalder et al 2010) and the Pacific (Kennett et al 2006b). The model describes how individuals choose which locations to settle based on comparing habitat suitability and population density in the place of origin against other potential locations ( Figure 2).…”

“…The IFD has been used to understand island colonisation from the Caribbean (Giovas & Fitzpatrick ), the Northern Channel Islands (Jazwa et al . ; Winterhalder et al . ) and the Pacific (Kennett et al .…”

Regional patterns of pastoralist migrations under the push of reduced precipitation in imperial China

“…The pastoralist minorities of China, migrating under the duress of reduced precipitation in search of better pastures, had to overcome the resistance of the residential agriculturalists who already occupied the most attractive presumably led to unequal access to resources (Jazwa, Kennett, & Winterhalder, 2016;Prufer et al, 2017). The pastoralist minorities of China, migrating under the duress of reduced precipitation in search of better pastures, had to overcome the resistance of the residential agriculturalists who already occupied the most attractive presumably led to unequal access to resources (Jazwa, Kennett, & Winterhalder, 2016;Prufer et al, 2017).…”