Body size and fatness of free‐living baboons reflect food availability and activity levels

Abstract

We used morphometric techniques and isotope-labeled water to investigate the influence of abundant, accessible food and resultant low activity levels on body size and fatness in free-living adolescent and adult baboons as compared to animals in the same population that experienced more typical, wild-feeding conditions. Females that had access to abundant food from a nearby garbage dump averaged 16.7 kg body mass, 50% more than their wild-feeding counterparts in adjacent home ranges. Little of the difference was due to lean mass: the animals with an accessible abundance of food averaged 23.2% body fat in contrast to 1.9% for the wild-feeding animals. Significant differences between feeding conditions were found for all measured skinfolds and for upper arm circumference but not for linear measurements. Differences between feeding conditions were less for males than for females, perhaps reflecting persistent effects of nutritional conditions during the first eight years of life before dispersal from the group of birth. The difference in fatness between feeding conditions was similar to the difference between humans with frank obesity and those that are considered lean, but in both cases the percentages of body fat in the baboons were considerably less than those observed in humans. In levels of fatness, the relatively sedentary animals resembled their counterparts in group-housed captive conditions. o 1993 WiIey-Liss, Inc.

The nature of nutrition: a unifying framework

“…While this is most common in captive primates (e.g. in zoos), significant levels of obesity have also been observed in free-ranging populations of baboons (Altmann et al 1993) and macaque monkeys on the island of Cayo Santiago off the coast of Puerto Rico (Schwartz et al 1993). In both cases this was associated not with natural foods, but with access to garbage dumps (baboons) and the management practice of supplementing the natural diet with primate chow (macaques).…”

Seasonal variation in the body fat of Japanese macaques Macaca fuscata.

“…Until the development of DXA, the only means to precisely measure total body fat mass in non-human primates were the isotope method (Altmann et al 1993), and dissection to extract as much fat as possible (McFarland and Zihlman 1997;Hayama et al 1998). The development of DXA has allowed total body fat mass to be accurately measured in 10 minutes or less.…”

“…Altmann et al (1993) reported that baboons in troops relying on garbage for food have 23.2% fat mass whereas, wild baboons, which do not depend on garbage, have as low as 1.9%. They also showed that females tend to carry more fat than males.…”

“…Although there have been numerous experimental studies of fat mass or obesity from the biomedical perspective (e.g. Colman et al 1999b), there have been few studies of wild or free-ranging populations (Altmann et al 1993). In the present study, fat mass data for Japanese macaques were obtained by DXA.…”

Feeding behavior, obesity, and neuroeconomics

“…An example more directly relevant to foraging is a study is of three troops of baboons in the Amboseli Naional Park, Kenya [77]. One troop had for many years incorporated the use of menu items from a dumpster at a tourist lodge, while the other two troops were exclusively wild-feeding.…”