Doctoral Dissertation Research: Guenon face patterns and the maintenance of primate reproductive isolation

New York University, New York NY

Investigators

Abstract

Reproduction and mate choice are key components of evolution because they affect how species are formed and maintained. In primates, there are several examples of closely-related primate species living in overlapping geographic ranges. How do these animals distinguish between members of their own versus other species when looking for mates? This doctoral dissertation project is an investigation of the role of face patterns and behavioral displays in maintaining reproductive isolation in the guenons, a group of forest monkey species in Africa that exhibit an extraordinary variety of colorful face patterns. Innovative methods will be used to measure and analyze the monkeys' appearance and their behavior related to members of their own species and closely-related species. Computer code and methodological details will be made freely available, and the project will support education and diversity in science through undergraduate training and K-12 science education outreach. The investigators will also be involved in scientific and biodiversity conservation outreach programs at their research site, and the project will foster international collaborations between research and conservation organizations in the USA and Nigeria. Identifying appropriate mates is potentially challenging for closely-related species with overlapping geographic ranges. One mechanism for preventing matings between different species is the evolution of signals that advertise species membership and that are used in mate choice to maintain reproductive isolation. Previous research has demonstrated that guenons can be classified by species based on images of their faces, and that facial distinctiveness increases with the degree of range overlap. However, the behavioral mechanisms by which a system of facial distinctiveness and associative mate choice might operate remain unclear. In this project, researchers will assess if and how guenons discriminate between species, and how variation in face patterns and behavioral displays influences mating decisions. To answer this question, researchers will: (1) identify regions of guenon faces critically important for species classification using computer vision algorithms; (2) assess guenon visual biases for same versus different species faces using a discrimination task with live guenons; (3) quantify behavioral displays and investigate their relationship with facial morphology using computer vision algorithms; and (4) document the ways in which guenon morphology and behavior are used in the wild using behavioral observations. This research will help to clarify the extent to which guenon face patterns function as signals of species membership, and how guenon morphologies and behaviors interact to influence their mating decisions. Ultimately, the results of this project will help us understand the relationship between phenotypic diversity and reproductive isolation.