The slender loris is a nocturnal primate of India and Sri Lanka. Diurnal primates, such as monkeys, apes and lemurs, have served as the primary subjects for testing hypotheses about the origin and adaptiveness of gregarious living in primates. Anthropologists have hypothesized that social groups are favored when primates utilize clumped food resources, such as fruit in a large canopy tree, or that social grouping is a correlate of primates' delayed life histories (i.e., slow growth and dependent childhood). Any robust hypotheses intended to explain primate sociality must be able to account for the specific cases of the less gregarious nocturnal primates. This study addresses the following general questions about lorises: 1) What are the social correlates of foraging for dispersed fruit or insect resources? 2) What are the social correlates of feeding upon spatially clumped food items? 3) What are the social correlates of delayed life history? Study methods are designed to statistically isolate and characterize the contexts in which lorises express social interactions, which in turn will test social theory developed from the diurnal primates. An additional significance of this study is that supplemental information obtained about habitat preferences and behavior will contribute to conservation of the threatened loris.
