Current Research and Scholarly Interests
How does social experience influence the brain?
Our research is focused on understanding the mechanisms through which social change is transduced into cellular and molecular change. Sex is the most potent selective force acting on animal behavior, shaping many aspects of animals’ behavior and physiology. How is vertebrate sexual maturation and behavior controlled? Ultimately, males regulate reproductive opportunity and success through their behavior and social interactions, selecting a mate from among males on offer. Males use a variety of competitive strategies, evolved to impress females, intending to become the chosen one. Amongst males, there is typically a status hierarchy in which males compete for highest rank that brings with it a higher chance of being chosen because high status leads to reproductive opportunity and competence as well as access to females and food. Lower ranking animals often have limited access to food and reproduction and are reproductively incompetent. To understand the circuitry responsible for male reproduction, we study the neural mechanisms of social ascent, assessing the changes in males as they ascend from low to high status. We use a uniquely appropriate fish model system dominance is reflected in maintaining a territory so when a vacated territory becomes available, a low-ranking male must quickly detect his absence, seize the opportunity to acquire this valuable resource, and initiate a dramatic transformation that spans from whole-organism behavior and coloration changes, to hormonal, cellular, and transcriptional-level changes throughout the body. In fact, within a matter of minutes, his appearance and physiology has changed radically as he prepares for a new lifestyle as a dominant and reproductively active territory holder. But social ascent happens over two timescales. Following the rapid changes described above that occur in minutes, the reproductive system also needs to ramp up so the male has sperm for mating. Though both of these systems are triggered by the recognition of social opportunity, we can show that they comprise distinct circuits in which different neural peptides are activated to achieve the changes needed.