S. Peter Henzi

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Testosterone-dependent secondary sexual characteristics in males may signal immunological competence and are sexually selected for in several species. In humans, oestrogen-dependent characteristics of the female body correlate with health and reproductive fitness and are found attractive. Enhancing the sexual dimorphism of human faces should raise(More)
Renewed interest in fission-fusion dynamics is due to the recognition that such dynamics may create unique challenges for social interaction and distinctive selective pressures acting on underlying communicative and cognitive abilities. New frameworks for integrating current knowledge on fissionfusion dynamics emerge from a fundamental rethinking of the(More)
Savannah baboons are one of the few mammalian species that do not exhibit seasonal reproduction patterns and are therefore ideally suited to study the effect of female reproductive states (cycling, pregnant, lactating) on cortisol levels independent of seasonal factors. Fecal samples from 10 free-ranging female chacma baboons (Papio hamadryas ursinus),(More)
There is an established and very influential view that primate societies have identifiable, persistent social organizations. It assumes that association patterns reflect long-term strategic interests that are not qualitatively perturbed by short-term environmental variability. We used data from two baboon troops in markedly different habitats over three(More)
We used data from adult female chacma baboons, Papio cynocephalus ursinus, to provide the first test of hypotheses on interchange trading and the structure of a biological market (Noë & Hammerstein 1994, Behavioral Ecology and Sociobiology, 35, 1–11) within a primate group. The interchange commodities selected were grooming and handling of infants less than(More)
Understanding human cognitive evolution, and that of the other primates, means taking sociality very seriously. For humans, this requires the recognition of the sociocultural and historical means by which human minds and selves are constructed, and how this gives rise to the reflexivity and ability to respond to novelty that characterize our species. For(More)
As large-bodied savannah primates, baboons have long been of special interest to students of human evolution: many different populations have been studied and dietary comparisons among them are becoming possible. Baboons' foraging strategies can be shown to combine high degrees of flexibility and breadth with selectivity. In this paper we develop and test(More)
Populations of baboon (Papio sp.) at geographic and climatic extremes for the genus show a tendency to one-male organization, whereas most baboons live in multimale social groups; this effect has been attributed largely to limitation of food supply, but baboons' complex diet has hindered proper nutritional analyses. To test these optimal-diet explanations(More)
Annual cycles in day length are an important consideration in any analysis of seasonal behaviour patterns, since they determine the period within which obligate diurnal or nocturnal animals must conduct all of their essential activities. As a consequence, seasonal variation in day length may represent an ecological constraint on behaviour, since short(More)
Chacma baboons (Papio ursinus)were studied in a mountain habitat where the effects of high altitude and latitude combine to produce conditions as harsh as those experienced by the desert or hamadryas baboon (P. hamadryas).The population density was as low as that of hamadryas baboons. A survey of populations at altitudes between 1400 and 3000 m showed a(More)