International Journal of Primatology 

About: International Journal of Primatology is an academic journal published by Springer Science+Business Media. The journal publishes majorly in the area(s): Animal ecology & Population. It has an ISSN identifier of 0164-0291. Over the lifetime, 2572 publications have been published receiving 106675 citations.

Evolution of primate social systems

Abstract: We review evolutionary processes and mechanisms that gave rise to the diversity of primate social systems. We define social organization, social structure and mating system as distinct components of a social system. For each component, we summarize levels and patterns of variation among primates and discuss evolutionary determinants of this variation. We conclude that conclusive explanations for a solitary life and pair-living are still lacking. We then focus on interactions among the 3 components in order to identify main targets of selection and potential constraints for social evolution. Social organization and mating system are more closely linked to each other than either one is to social structure. Further, we conclude that it is important to seek a priori measures for the effects of presumed selective factors and that the genetic contribution to social systems is still poorly examined. Finally, we examine the role of primate socio-ecology in current evolutionary biology and conclude that primates are not prominently represented because the main questions asked in behavioral ecology are often irrelevant for primate behavior. For the future, we see a rapprochement of these areas as the role of disease and life-history theory are integrated more fully into primate socio-ecology.

Evolutionary Consequences of Fallback Foods

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.

Dietary Response of Chimpanzees and Cercopithecines to Seasonal Variation in Fruit Abundance. II. Macronutrients

Abstract: In a continuation of our study of dietary differentiation among frugivorous primates with simple stomachs, we present the first comparison of differences in dietary macronutrient content between chimpanzees and cercopithecine monkeys Previously we have shown that chimpanzee and monkey diets differ markedly in plant part and species content We now examine whether this diet diversity is reflected in markedly different dietary macronutrient levels or the different feeding strategies yield the same macronutrient levels in their diets For each primate group we calculated the total weighted mean dietary content of 4 macronutrients: crude lipid (lipid), crude protein (CP), water-soluble carbohydrates (WSC), and total nonstructural carbohydrates (TNC) We also calculated 4 fiber fractions: neutral-detergent fiber (NDF), which includes the subfractions hemicellulose (HC), cellulose (Cs), and sulfuric acid lignin (Ls) The HC and Cs are potentially fermentable fibers and would contribute to the energy provided by plant food, depending on the hind gut fermenting capacity of the individual primate species The chimpanzee diet contained higher levels of WSC and TNC because during times of fruit abundance the chimpanzees took special advantage of ripe fruit, while the monkeys did not The monkey diets contained higher levels of CP because the monkeys consumed a constant amount of leaf throughout the year All four primate species consumed diets with similar NDF levels However, the chimpanzees also took advantage of periods of ripe fruit abundance to decrease their Ls levels and to increase their HC levels Conversely, the monkey diets maintained constant levels of the different fiber fractions thoughout the year Nevertheless, despite these differences, the diets of the 4 frugivores were surprisingly similar, considering the substantial differences in body size We conclude that the chimpanzee diet is of higher quality, particularly of lower fiber content, than expected on the basis of their body size

Changes in Orangutan Caloric Intake, Energy Balance, and Ketones in Response to Fluctuating Fruit Availability

Abstract: I used novel quantitative measures to assess the impact of fruit seasonality on changes in diet and energy balance during 4918 hours of observation on <60 orangutans in Gunung Palung National Park, West Kalimantan, Indonesia, from September 1994 through September 1995. During this period a mast fruiting occurred, resulting in large fluctuations in fruit availability, measured by monitoring of 558 orangutan fruit trees. Orangutan diet varied tremendously in accordance with these fluctuations. During the month of highest fruit production, 100% of the orangutan diet was composed of fruit. In contrast, during the fruit-poor period as little as 21% of the diet was fruit, while 37% was bark. Nutritional analyses of 78 of the foods most commonly eaten during this study show that mast foods were significantly higher in caloric content than were nonmast foods, which translates into substantial changes in caloric intake. During the month of highest fruit consumption (January), males consumed an estimated 8422 kcal/day and females consumed 7404 kcal/day. During the month of lowest fruit consumption (May), males consumed 3824 kcal/day and females consumed 1793 kcal/day. These differences were significantly different between the 2 months for both males and females. In May, males ate significantly more kcal/day than females did. Time spent feeding did not differ between the two periods for either males or females. I assessed the impact of these changes in diet and caloric intake on orangutan physiological functioning by measuring ketones in 257 urine samples collected from adult males and females. Ketones—products of fat metabolism—were present in urine only during the fruit-poor period. These data suggest that orangutans are highly efficient at storing fat during fruit-rich periods and utilizing the reserves during times of fruit shortfall. This response may have important implications for orangutan survivorship, reproduction, and behavior.

Responses of rain-forest primates to habitat disturbance: A review

Abstract: The survival of primates in moderately disturbed forests is determined by a complex of variables. Correlation analyses suggest that ecological features of a species may confer a basal survival ability but that details of the form of disturbance may be crucially important. Correlation analyses reveal that body size alone is a poor predictor of primate response to moderate forest disturbance. However, when the effects of diet variables are held constant, body size more strongly correlates with survival ability (smaller species surviving better). Degree of frugivory shows a significant negative correlation with survival ability at both univariate and multivariate levels of analysis. In contrast, dietetic diversity is not correlated with survival ability at either level of analysis. Together, body size and percentage frugivory explain 44% of the variation in species’ responses to moderate habitat disturbance. Idiosyncratic responses of species can usually be traced to specific features of the changing environment, such as selective elimination of important food sources and, conversely, the presence of increased densities of particular food sources arising from the disturbance.