Degree of terrestrial activity of the elusive sun-tailed monkey (Cercopithecus solatus) in Gabon: Comparative study of behavior and postcranial morphometric data

We carried out a multidisciplinary study linking behavioral and morphological data from a little-known guenon species, Cercopithecus solatus, endemic to Gabon. Over a period of 9 months, we documented the pattern of stratum use associated with postural and locomotor behavior by direct observation (650 hrs) of a semi-free-ranging breeding colony. We also conducted a morphometric analysis of the humerus and limb proportions of 90 adult specimens from 16 guenon species, including C. solatus. Field observations indicated that C. solatus monkeys spent a third of their time on the ground, similar to semi-terrestrial guenon species. We detected two patterns of stratum use: at ground level, and in …