Growth, development, and sexual dimorphism in vervet monkeys (Cercopithecus aethiops) at four sites in Kenya

Abstract

Body weight and ten body segment measurements were collected from 367 wild-trapped vervet monkeys (Cercopithecus aethiops) in central and southern Kenya. The animals represent between 70 and 95% of the animals in each of 30 troops at four geographical locations separated by 80 to 380 km. The capture sites differed in altitude, mean annual rainfall and temperature. Two questions are addressed: (1) what are the differences in male and female growth patterns, and (2) what is the relationship between size, climate, and availability of food? Each animal was assigned to an age class based on dental examination. Means for all variables do not diverge for males and females from birth to age class 4 (15-18 months). After this, male and female growth rates diverge. This sexual dimorphism in growth pattern may reflect timing of entry into the reproductive community. A nested analysis of variance (ANOVA) was employed to compare sites, groups within sites and individuals within groups. Statistically significant differences between sites in body weight and body segment measurements are found for adult females. Except for tail length, these differences do not follow Bergmann's or Allen's Rules correlating size differences and temperature, but rather may reflect proximity to cultivated areas or tourist lodges with greater access to human food.

Thoracic radiographic anatomy in vervet monkeys (Chlorocebus sabaeus)

“…Although positive pressure ventilation was applied during the acquisition of radiographs, mild gravity‐dependent atelectasis likely persists, particularly in lateral views. A similar radiographic finding was reported in anesthetized macaques and marmosets , in which radiographs were made without positive pressure ventilation. The mild bronchointerstitial pattern obscured consistent evaluation of the aorta, CVC, and pulmonary arteries and veins.…”

A comparison of adult body size between captive and wild vervet monkeys (Chlorocebus aethiops sabaeus) on the island of St. Kitts

“…These same kinds of differences—in mass and weight and not in length and morphological measures were also observed in a series of wild populations in Kenya where some groups of animals were exposed to human food while other populations were not (Turner et al, 1997). In this case, animals with access to human food were heavier than those without access.…”

Females are the ecological sex: Sex‐specific body mass ecogeography in wild sifaka populations (Propithecus spp.)

“…There has historically been a focus on the role of male body size in response to sexual selection in the evolution and maintenance of sexual dimorphism, which has led to body size dimorphism in the primate fossil record (and especially the hominin fossil record) being interpreted primarily in the context of male competition levels and associated social structures (e.g., Lovejoy, 1981;McHenry, 1991;Richmond and Jungers, 1995;Reno et al, 2003;Gordon et al, 2008;but see McHenry, 1996;Plavcan, 2002;Gordon, in press). Multiple studies have documented intraspecific differences in size dimorphism between primate populations where those populations fall along an ecological gradient in which body size is correlated with environmental quality in both sexes, but dimorphism variation is driven by greater differences between populations in female body mass rather than male body mass (e.g., Ravosa et al, 1993;Turner et al, 1997;Johnson et al, 2005;Gordon, 2006a). Multiple studies have documented intraspecific differences in size dimorphism between primate populations where those populations fall along an ecological gradient in which body size is correlated with environmental quality in both sexes, but dimorphism variation is driven by greater differences between populations in female body mass rather than male body mass (e.g., Ravosa et al, 1993;Turner et al, 1997;Johnson et al, 2005;Gordon, 2006a).…”