Marmoset Social Spacing

"Classical" (mating, nesting, breeding, feeding) territories are utilized by marmosets almost exclusively. The reason why this species evolved the classical territory is due to predation pressures. Marmosets sleep and hide in tree holes of old trees in the rainforest. When they retire, they huddle in a ball inside these holes. There is a high demand for these holes, from both other marmosets and other species, such as birds (Ferrari 1990). They need for this habitat is due to the large predation pressures from aerial raptors. Patroling of the large territorial area occurs daily, and most aggression occurs between marmosets of the same sex (Michels, 1998).

Of the three purposes of scent-marking: defense of home range, social status, and reproductive uses, the marmoset almost exclusively uses it for defending its home range (Lazaro-Perea, 1999). For this animal, reproductively dominant females do not scent mark more that subordinate females and, in fact, found that subordinate females scent marked more than the breeding female. Also, scent marking do not take place near the edges of the marmoset territories. Scent marking is not directly tied to reproduction (Lazaro-Perea, 1999). In marmosets, scent marking is used as a common method of olfactory communication that is directly related to the social spacing of this species (Thiessen, 1976). Specifically, for the marmoset, the official classification of the scent marking is "sebaceous glands on sternal and gular areas" and it was found that "marking in dominant male increases after fighting encounters but not in female; objects marked by other marmosets stimulate marking" (Thiessen, 1976). New perches available to the marmosets are marked immediately by the dominant male (Thiessen, 1976)..

Much of the marmosets' time during the day is spent watching for predators. They only use alarm calls when predators approach their sleeping site. Marmosets also relate directly to falconiforms that appear overhead. The use of "sentinels" is also a common practice of the marmoset (Ferrari, 1990).

The dominant female gives birth to two nonidentical twins at a time, and these twins show particular interest in playing with each other in manner that is unique when compared to other play interactions (Stevenson, 1982). Marmoset play behavior itself does not change with age, though it's frequency does significantly. Play is related directly to social activity, and does not seem related to aggression, as the behavioral characteristics between the two activities are very different (Stevenson, 1982).