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  • Cited by 45
  • Print publication year: 2005
  • Online publication date: August 2009

6 - Seasonality and long-term change in a savanna environment

    • By Susan C. Alberts, Department of Biology Duke University Box 90338 Durham NC 27708 USA; Institute for Primate Research National Museums of Kenya Nairobi Kenya, Julie A. Hollister-Smith, Department of Biology Duke University Box 90338 Durham NC 27708 USA, Raphael S. Mututua, Amboseli Baboon Research Project Amboseli National Park Kenya; Institute for Primate Research National Museums of Kenya Nairobi Kenya, Serah N. Sayialel, Amboseli Baboon Research Project Amboseli National Park Kenya; Institute for Primate Research National Museums of Kenya Nairobi Kenya, Philip M. Muruthi, African Wildlife Foundation Box 48177 Nairobi Kenya, J. Kinyua Warutere, Amboseli Baboon Research Project Amboseli National Park Kenya; Institute for Primate Research National Museums of Kenya Nairobi Kenya, Jeanne Altmann, Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544 USA; Department of Conservation Biology Brookfield Zoo Brookfield, IL USA; Institute for Primate Research National Museums of Kenya, Nairobi, Kenya
  • Edited by Diane K. Brockman, University of North Carolina, Charlotte, Carel P. van Schaik, Universität Zürich
  • Publisher: Cambridge University Press
  • DOI:
  • pp 157-196



The emergence and spread of savannas in Africa during the past five million years is often cited as a major factor in hominid evolution. Tropical savannas are different from forests in having less rainfall, which is strongly seasonal and often very unpredictable, even within seasons (Bourliere & Hadley 1983; Solbrig 1996). Human ancestors are thought to have moved into savannas as a response to cooling and drying climates, and the exigencies of the savanna environment – including the marked seasonal changes in plant food availability – are often cited as key selective pressures shaping the hominid lineage (see reviews and references in Foley [1987, 1993], Potts [1998a, 1998b], Klein [1999], and Chapters 4, 5, and 17). This scenario invites a careful examination of responses to seasonality in extant savanna-dwelling primates.

Like most vertebrates, the large majority of primate species exhibit reproductive seasonality that reflects the seasonality of their habitats (see review in Chapter 11). Indeed, among savanna-dwelling primates, there are only two exceptions to the rule of seasonal reproduction: humans and baboons (genus Papio). This shared characteristic – the ability to reproduce throughout the year in seasonal environments – may be related to the extraordinary success of these two genera. While only humans (and their commensals) have spread across the globe, baboons have achieved a nearly continental distribution in Africa.

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