The social organizations of squirrel monkeys: Implications for ecological models of social evolution

Abstract

“Squirrel-monkeys occur in a considerable number of slightly different forms, but all are built upon a similar body plan and have a basic color scheme. One of the larger races—from inner Peru—is also the most colorful and one of the brightest colored of all mammals. It may be taken as a point of departure. The top of the head and the upper and outer parts of the body and the upper side of the basal half of the tail are a vivid green, with a pepper and salt effect of yellow and gray. The face is pure white except for black spectacles, muzzle and chin; the throat, chest, underside, insides of limbs, and the underside of the basal half of the tail are brilliant daffodil yellow. The terminal half of the tail is jet black and rather bushy. The flesh of the hands is pale pink. Other races vary in the intensity of the green and yellow, so that some may be olive brown above and white below, and in the amount and arrangement of the black areas on the face and the tip of the tail. Some have almost naked ears, others have these organs clothed in short fur, and still others bear thereupon long tufts or fringes. All these variations seem to blend into the other geographically . . . some of these pure color variations may constitute valid regional subspecies or even species. . . .” I. T. Sanderson1 (p. 77).