Determination of Genealogical Relationships from Genetic Data : A Review of Methods and Applications

The concept of kinship has been central to investigating the remarkably varied social structures of primates . Genealogical relationships between individuals are predicted, from the first principles of evolutionary theory, to be critical influences on the nature of social relationships . Sociobiological/socioecological theory in particular predicts that kinship should have primary importance for the cohesion of groups, dominance, inbreeding avoidance, and coalitional behavior (Hamilton 1964, Wrangham 1980, Trivers 1985, Silk 1987) . Determining kinship is therefore a major focus of many studies of primate sociality . Kinship information has proven indispensable to addressing questions relevant to the evolution of sociality, mate choice, breeding systems, social dominance, and kin selection (Ross 2001). Consequently, investigators have used many direct and indirect methods to try to determine kinship relationships in primate groups . Among these, the most powerful, and currently the most widely used, are the molecular genetic methods . Molecular genetic methods for determining kinship vary in their accuracy and in the amount of effort, expertise, money, and error involved . This chapter reviews molecular genetic methods that are commonly used or potentially useful in studies of primate kinship . Methods are reviewed with respect to their relative costs and benefits in terms of effort, financial cost, expertise, or specialized equipment, as well as with respect to the limitations of the inferences that can be drawn from them . A short review of the published applications of molecular methods for determining genealogical relationships follows to put the use of these methods into historical as well as methodological perspective . The following sections describe potential sources of genetic material and the various classes of genetic markers commonly used in studies of primate kinship . Because of the current popularity and accessibility of DNA-based methods, we will not consider genetic methods that make use of other molecules (RNA, proteins) . The goal is to provide informa-