I study how individual differences in behavior and genetics mediate the physiological response to chronic social stress. Along with my advisor and our collaborators, I carry out this work using a non-human primate model of chronic social stress - dominance hierarchies (i.e., social status) in captive female rhesus macaques. As in humans, chronic social subordination in this species has strong effects on immune function, endocrine regulation, and genome-wide gene regulation. However, there is substantial variation in individual susceptibility and response to the same sources and levels of social stress. Developing effective interventions to address its negative consequences is therefore contingent upon our understanding of the sources of this inter-individual variability.

To carry out this work, I merge cutting-edge functional genomic analyses with behavioral observation methods to study how genetic and behavioral variation might insulate individuals from the detrimental effects of social stress on health. Interestingly this research also has implications for understanding how social stress recapitulates, or even accelerates, the changes seen during normal aging.

Funding: NIH R01GM102562, T32AG000139; NSF SMA-1306134

Collaborators: Jenny Tung, Mark Wilson, Luis Barreiro

Past Research

Sociality, song-learning and fitness in brown-headed cowbirds (Molothrus ater)

The evolution of cooperation and sociality in the multi-level society of geladas

Inter-individual variation in the response to social stress in rhesus macaques (Macaca mulatta)

Photo by DJ White

Photo by LJN Brent

Photo by N Snyder-Mackler

In collaboration with the University of Michigan Gelada Research Project (UMGRP) and Dr. Susan Alberts at Duke University, I have studied the socio-genetic structure of geladas (Theropithecus gelada). My research has incorporated both field and laboratory techniques, in which I used non-invasive genetic sampling techniques to determine relatedness between individuals and groups in the multi-level society of gelada. Using this two-pronged approach I have examined the interactions between genetics, relatedness, cooperation, and sociality in the complex society of geladas.

Funding: NSF BCS-0962118, BCS-0715179, GRFP)

Collaborators: Thore Bergman, Jacinta Beehner, Susan Alberts

For my MA thesis I studied the interaction between sociality and song development in the brown-headed cowbird. Male cowbirds produce many different song types across a variety of social contexts. This research focused on when males produced their different song types and how increased social experience affected their reproductive success. I also studied how the social environment affects the development of all aspects of song (song potency, repertoire size) in juvenile cowbirds.

Collaborators: David White

Over the past few decades, the development of methods to generate genetic data from low-quality or non-invasively collected samples has revolutionized the study of evolution and ecology in natural populations. However, these methods have changed little over the past twenty years. Typical studies focus on only a dozen or so regions of the genome - amounts of data that pale in comparison to those routinely generated using high-throughput sequencing technologies.

Non-invasively collected samples generally contain small amounts of low-quality DNA, making it inefficient and expensive to sequence using standard high-throughput techniques. In this line of research, my collaborators and I have developed the lab and computational methods necessary to bring the “genomics revolution” to species from which samples can only be obtained non-invasively. Specifically, we have developed methods to generate genome-scale genetic information from low-quality, non-invasively collected samples as well as the computational tools necessary to analyze such data.

You can find the manuscript here, the wet lab protocols here, and the paternity inference program, WHODAD, here.

Funding: NSF DEB-1405308

Collaborators: Jenny Tung, Sayan Mukherjee, Xiang Zhou

Methods for genome-scale sequencing from non-invasively collected samples

Photo by N Snyder-Mackler

Current Research

Gene regulatory effects of social integration and resilience during aging

More socially connected individuals are healthier and live longer, possibly due to an improved ability to cope with acute stress – a hypothesis known as “social buffering”. This project investigates how variation in social connectedness alters immune related gene regulation in response to an acute stressor. The results of this project will greatly advance our understanding of the role that the quality and quantity of interpersonal relationships play in healthy aging, which will help us address pressing biological and societal questions.

Funding: NIH AG5T32AG000029, R01GM102562

Collaborators: Jenny Tung, Mark Wilson, Luis Barreiro

Photo by LJN Brent