Research

Our research integrates genetic analyses with behavioral, morphological, and environmental data to address questions about primate evolution.

Although our research spans several topics, from behavioral genetics to the evolution of hair color, all of these projects ultimately address larger over-arching questions: Ÿ

 

  • Do convergent primate phenotypes come about via convergent proximate mechanisms? That is, when distantly related species independently develop similar traits (e.g. red hair, color vision, flat faces) is this usually due to similar changes at the molecular level (same mutation, same gene, same pathway)? 

 

  • Does the proximate provide a clue to the ultimate? Understanding which genes, polymorphisms, and pathways underlie specific phenotypic variation can inform our hypotheses about the evolutionary forces acting on those traits. For example, if we find that sexually dichromatic traits (e.g. differences in coat color) are often due to differences in the expression of genes regulated by hormones or elements in the diet, we can understand how sexual selection shapes this aspect of primate phenotypic diversity. Ÿ

 

  • How do the forces of micro-evolution shape the social structure of primate communities? Biologists quantify evolution at the population level. Yet, the major factors that drive evolution - selection, drift, migration - are difficult to observe and document in wild primate populations. In collaboration with field primatologists, we utilize an indirect approach to studying these factors through genetic analyses of wild primates.

 

To these ends, research in the lab falls under two themes: 1)  identifying the genetic bases of primate adaptations and diversity; and 2) examining the genetic structure of wild primate populations.

 

Genetics of Primate Adaptation and Diversity

 

Despite the general acceptance that natural selection has shaped animal morphology and behaviour via alterations in the genotype, there are surprisingly few cases where specific genetic changes are known to modify phenotypes in a way that demonstrably increases fitness. We are examining genetic polymorphisms that might underlie interesting aspects of primate diversity and adaption This has included research on genes associated with facial morphology, eye color, meat-eating, sensory ecology, and behavioral tendencies. Current research in the lab largely focuses on genes involved in primate pelage pigmentation, morphology and growth.

 

Much of this work is done in collaboration with Nick Mundy at the University of Cambridge, Rich Lawler at James Madison University, and  Jason Kamilar at Midwestern University.

 
Genetic Structure of Wild Primate Populations

 

We also use neutral genetic markers to examine aspects of sociality and ecology in wild primate populations. By analysing DNA from noninvasive samples (e.g. hair and feces) we measure reproductive success and identify kinship networks within and among wild primate social groups. This includes, for example, studies of wild gorilla social structure and research on kinship and cooperation in wild lemurs.   

 

A newer project in the lab examines the population genetics of humans (ancient DNA) at Machu Picchu, in collaboration with Lars Fehren-Schmitz,  Richard Burger and Lucy Salazar. 

 

 

Illustrations copyright Stephen D. Nash/CI. Used with permission.