Doctoral Dissertation Research: Early-life adversity: Maternal effects in a wild primate

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

In early life, organisms receive cues about their environment from their mother, specifically her hormones. But how offspring respond to these signals is not fully understood. This doctoral dissertation project will examine how the early-life environment and maternal “stress” hormones impact development in a long-lived, wild primate. In humans, high maternal stress can result in low offspring birth weight, which in turn predicts poor physiological status later in life. By studying a wild primate, this research will help identify why these connections exist and could inform interventions designed to help prevent negative outcomes. Additionally, this project will contribute to conservation and education at the research site and surrounding areas, through frequent presentations to local community members, tourists, and park management officials. The co-PI will also continue to mentor undergraduate women in the laboratory throughout her dissertation. When faced with adversity, mammalian mothers have fewer resources to invest in their offspring. These mothers also experience higher levels of “stress” hormones. These hormones, through the placenta and breastmilk, can reach the offspring and indicate the mother’s divestment, potentially leading to adjusted offspring development in response to these signals. There are two possible adjustments that can occur in offspring: 1) a delay in all aspects of development, or 2) trade-offs in development, for example favoring growth over investment in the immune system. Using non-invasive fecal hormone samples, this project will first identify the social and ecological factors of the environment that result in higher maternal stress hormones. Next, using behavioral observations, the researchers will examine if maternal stress levels impact maternal behavior towards their offspring. Lastly, the researchers will non-invasively assess four aspects of offspring development (growth rate, motor skill acquisition, time to independence, and immune function) to determine if offspring respond to maternal stress hormones by delaying all developmental markers or by making trade-offs. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.