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The benefits of spatial memory for foraging animals can be assessed on two distinct spatial scales: small-scale space (travel within patches) and large-scale space (travel between patches). While the patches themselves may be distributed at low density, within patches resources are likely densely distributed. We propose, therefore, that spatial memory for recalling the particular locations of previously visited feeding sites will be more advantageous during between-patch movement, where it may reduce the distances traveled by animals that possess this ability compared to those that must rely on random search. We address this hypothesis by employing descriptive statistics and spectral analyses to characterize the daily foraging routes of a band of wild hamadryas baboons in Filoha, Ethiopia. The baboons slept on two main cliffs-the Filoha cliff and the Wasaro cliff-and daily travel began and ended on a cliff; thus four daily travel routes exist: Filoha-Filoha, Filoha-Wasaro, Wasaro-Wasaro, Wasaro-Filoha. We use newly developed partial sum methods and distribution-fitting analyses to distinguish periods of area-restricted search from more extensive movements. The results indicate a single peak in travel activity in the Filoha-Filoha and Wasaro-Filoha routes, three peaks of travel activity in the Filoha-Wasaro routes, and two peaks in the Wasaro-Wasaro routes; and are consistent with on-the-ground observations of foraging and ranging behavior of the baboons. In each of the four daily travel routes the 'tipping points' identified by the partial sum analyses indicate transitions between travel in small- versus large-scale space. The correspondence between the quantitative analyses and the field observations suggest great utility for using these types of analyses to examine primate travel patterns and especially in distinguishing between movement in small versus large-scale space. Only the distribution-fitting analyses are inconsistent with the field observations, which may be due to the scale at which these analyses were conducted. Am. J. Primatol. 76:421-435, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Group size is a fundamental aspect of the adaptation of a social animal to its environment. There have thus been numerous attempts to infer optimal group sizes based on both empirical studies of specific taxa and theoretical models that aim to establish generalities. One such generality is that larger groups experience greater within-group foraging competition because of either direct interference by other group members or the rapid exploitation of resources. The ecological constraints hypothesis proposes that increases in group size will increase intragroup feeding competition, thus forcing individuals to visit more patches and to cover greater areas than they would in smaller groups. This paper provides a simple formal model of this constraint, suggesting that two types of constraint limit group sizes in this scenario. First, a constraint on time available to reach an energetic threshold may limit groups to sizes that allow each individual forager to attain that threshold. Second, the balance of foraging costs to benefits may curtail group size even in the absence of a temporal constraint. Both these constraints can be obviated by the adoption of fission–fusion social systems in which a group divides into subgroups during foraging. This latter finding is discussed in relation to primate social systems with an emphasis on time budget approaches. [Copyright &y& Elsevier]

Abstract: Increasing carnivory is frequently cited as one of the key trajectories in the course of hominin evolution, yet the ethnographic record demonstrates that hunting is a high-variance, risky strategy necessitating a fundamental re-organisation of the foraging pattern. Hunter-gatherers rely on intra-band sharing of hunted resources as well as inter-band insurance mechanisms to mitigate against the risk of resource failure. It is suggested that logistical mobility functions to increase encounter rates with both prey and representatives of neighbouring groups, and is thus a fundamental part of the hunting adaptation. Implementation of an ideal gas model of encounter rate demonstrates that, when logistical mobility is regarded as a basic group fission pattern, it increases encounter rates for all groups relying on greater than 34% hunting. This equates to a shift in the optimal hunting percentage, as defined by encounter rates, from 24% under residential mobility to 35% under a logistical mobility strategy. These results are discussed in relation to fission–fusion social systems in primates and social carnivores, with a view to highlighting the specific aspects in which these differ from human foraging strategies. [Copyright &y& Elsevier]

The role of the environment in shaping agricultural origins is still not fully understood, despite a century of debate on this topic. Comparison of the expected prevalence of a resource in the landscape with actual archaeological presence of the same resource can provide a metric for assessing resource choice in prehistory. However, the palaeoenvironmental data that would allow resource choice to be evaluated in this way are rarely available. Species Distribution Modelling (SDM) techniques allow independent palaeoenvironmental datasets to be computed, which when compared to actual species’ presence at sites as attested by archaeological datasets, can provide data on resource choice. Following recent calls for SDM to be applied more widely in archaeological contexts, we outline a simple method for predicting the presence of plant species in prehistory using modern analogues and palaeoclimatic datasets. These modelled distributions provide an independent dataset for comparison with archaeological data, thus providing a window into human resource choice in prehistory. We outline the method with specific reference to the transition from foraging to farming in the Neolithic of Central Anatolia, but the method could be applied to any period or region. We have used exclusively open source data and provided all code in our online supplementary materials, so that our method can be utilized by researchers interested in human resource choice in any region of the world and any period. [ABSTRACT FROM AUTHOR]