Population Structure of Night Monkeys (Aotus) through Genetic and Behavioral Analysis

Social structure, population demogrpahy, and patterns of radiation and dispersal can all affect patterns of diveristy and, in some instances, may be evaluated using genetic data. Highly variable DNA microsatellites provide a useful tool for analyzing population structure and may confirm kinship relationships, such as paternity.

The Aotus azarae population of Formosa, Argentina, studies by CRES Conservation Research Fellow Dr. Eduardo Fernandez-Duque, has served as a valuable model population for exploring these questions. In order to evaluate microsatellite genetic diverstiy, variable micorsatellite loci need to be identified.

In 2004, the first paper on microsatellite diversity in Aotus was published in a collaborative study involving the division of Genetics at the San Diego Zoo's CRES, as well as the Dumond Conservancy. A reference population of Aotus azarae, Aotus lemurinus, and other Aotus species was assembled from samples in CRES's Frozen Zoo and the Dumond Conservancy. Screening these populations for microsatellite diversity by PCR, using primers conserved between Old World monkeys and humans, identified 20 informative loci in the reference population. Transmission of microsatellite alleles could be verified with families of Aotus individuals that comprised the referenced populations. Screening of the small number of wild Aotus azarae suggested that the Formosa study population was more limited in genetic diversity than the individuals in the captive reference population.

Thus, while this first study of its kind identified new tools for population analysis linking behavioral ecology and population genetics, establishing paternity and kinship within the Formosa population requires identification of additional variable loci.