Developmental Flexibility in Spotted Hyenas: The Role of Maternal and Anthropogenic Effects
Spotted hyenas make an excellent model system in which to study mammalian responses to environmental change due to their remarkable flexibility. Dr. Kay Holekamp and the MSU Hyena Project have documented behavioral and physiological changes in adult hyenas that are associated with increased human disturbance. We can study these changes by conducting: 1) longitudinal analyses of how our study populations have changed since our project began in 1988, and 2) cross-sectional analyses of hyenas living in areas with different degrees of human disturbance.
In my dissertation research, I am exploring how the spotted hyena's unusually protracted developmental period helps to shape this flexibility. Specifically, I am testing the hypothesis that spotted hyena females transmit information to offspring about environmental disturbance through maternal effects. I predict that the temperaments and life history trajectories of young spotted hyenas are shaped, in part, by maternal behavior and stress physiology. I also hope to shed light on whether such maternal effects may serve an adaptive function and be one of the mechanisms underlying hyenas' ability to exist in a variety of habitats and adjust to changes in their environments.
To test this hypothesis, I am integrating several approaches described below.
Behavioral Observation of Mothers & Cubs
Experimental Tests of Cub Temperament
Stress Physiology and Maternal Hormones
In the field, we collect hyena feces, plasma, and milk for hormone analysis. Back in the US, I collaborate with Dr. Jacinta Beehner and Dr. Jeff French to assay these samples for corticosterone and progesterone.
In the field, I conduct experiments that allow me to assess dimensions of cub temperament, such as boldness, neophobia, and reactivity. Video coding of these trials allows me to explore how cub development and personality may be shaped by disturbance and social contexts.
In the field, I conduct focal follows on mothers and cubs. I combine this fine-grained behavioral data with space use information from GPS-collared mothers to gain an understanding of how ecological, anthropogenic, and social factors shape maternal styles and mother-offspring interactions.