Studying the wild population of yellow baboons (Papio cynocephalus) in the Amboseli National Park of southern Kenya, the Alberts Lab focuses on how animals respond behaviorally to their social environment. As a matrilocal species, female baboons stay within the group they are born into while males will disperse to another group. Male baboons compete with each other for access to resources, such as food and reproductive opportunities, therefore leading to a dominance social hierarchy.
With on-site, documented interactions between baboons and the ability to analyze hormone concentrations from collected fecal samples, my mentor explored the relationship between dominance rank and stress in male baboons. Gesquiere et al. (2011) found that the concentration of the stress hormone glucocorticoid in fecal samples was high in alpha and low-ranking males. However, beta males had significantly lower levels of glucocorticoid compared to alpha males, with the concentration of glucocorticoid increasing the lower in rank an individual is.
This summer, I am continuing Dr. Laurence Gesquiere’s research. In order to determine potential differences in stress experienced by alpha and low-ranking male baboons, I will determine the thyroid hormone concentration in fecal samples. Thyroid hormone is being analyzed because the thyroid gland secretes more or less of the hormone based on changes in metabolism, therefore allowing the hormone to be used as a measurement of energetic stress. Energetic stress caused by agonistic interactions and mating activities is believed to be the major source of stress for alpha males. In contrast, it is hypothesized that low-ranking males experience energetic stress from limited access to food and psychosocial stress from harassment from higher-ranking males.
Therefore, by looking at the thyroid concentration present in fecal samples from male baboons, I will help elucidate different sources of stress between low-ranking male baboons and the alpha males.
And as promised last week, here’s a picture of me working in the lab:
Me aspirating samples before they go into the gamma counter. Picture courtesy of my mentor!
