Abstract
Primatologists use the term fallback foods to denote resources of relatively low preference that are used seasonally when preferred foods are unavailable. We examine the assumption that fallback foods play an important role in shaping morphological adaptations, behavior, and socioecology in primates. We discuss operational definitions of preferred and fallback foods and suggest that the evolutionary importance of fallback foods applies more to adaptations for processing than for harvesting foods. Equally, we propose that preferred resources tend to drive adaptations for harvesting foods. We distinguish 2 classes of fallback foods according to their roles in the diet and their evolutionary effects. Staple fallback foods are available year-round, tend to be eaten throughout the year, and seasonally can constitute up to 100% of the diet. Filler fallback foods never constitute 100% of the diet, and may be completely avoided for weeks at a time. We suggest that the availability of the 2 classes of fallback foods have different effects on the socioecology of primate species.
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Acknowledgments
Our thinking about the issues discussed here benefited substantially from numerous productive discussions with Mark Leighton, and we thank him for his input. We also thank Herman Pontzer, David Pilbeam, and 3 anonymous reviewers for helpful comments and discussion. A. J. Marshall gratefully acknowledges Conservation International and The Arnold Arboretum of Harvard University for postdoctoral support. Some of the concepts considered in this article are cogently discussed in a new book by Brockman and van Schaik (2005) that was published as this article was in its final stages of revision. Readers are encouraged to consult this volume (especially Hemingway and Bynum 2005; Knott 2005).
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Marshall, A.J., Wrangham, R.W. Evolutionary Consequences of Fallback Foods. Int J Primatol 28, 1219–1235 (2007). https://doi.org/10.1007/s10764-007-9218-5
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DOI: https://doi.org/10.1007/s10764-007-9218-5