The molecular ecology of lemur societies Peter M. Kappeler1,2 1Department of Behavioral Ecology & Sociobiology, German Primate Center, 2Department of Sociobiology/Anthropology, University of Göttingen, Germany Abstract The extant primates of Madagascar (Lemuriformes) comprise more than 50 species in five families, which represent the endpoints of an adaptive radiation following a single successful colonization of the island more than 50 million years ago. During this long period of isolation, lemurs evolved a stunning diversity in life history traits and social systems that provide an opportunity to study convergent evolution with other primate radiations. My students and I have used genetic tools to describe the genetic structure of solitary, pair-living and group-living lemurs to provide data on the genetic structure of lemur societies for such comparative analyses. Previous comparative studies revealed that group-living lemurs, in particular, exhibit a number of traits that apparently deviate from basic predictions of sexual selection and kin selection theory. We therefore also collected genetic data on reproductive success, reproductive skew and patterns of relatedness to test hypotheses that attempt to explain these lemur idiosyncrasies. Our preliminary results indicate that lemur societies exhibit more diversity in genetic structure and less divergence from predictions of sexual selection and kinship theories than previously thought.