Kinship Behavior in Social Organization

Professor of Biology Christine Maher studies the evolution of social behavior – the understanding how ecological factors shape the behavior patterns of individuals and influence their reproductive success. For the past 14 years, she has led a long term study of woodchucks at Gilsland Farm in Falmouth, Maine. The woodchuck (or groundhog) was chosen for two reasons: 1) it is the least social member of the marmots and thus represents an early stage in the development of sociality, and 2) it is behaviorally flexible, meaning that different populations exhibit different degrees of sociality. Each season, individuals are captured and marked so they can be followed through time. As a result, the genealogy of nearly every woodchuck in the population is recorded, sometimes going back four or five generations. The research has shown that kinship does play an important role in the social organization. Both males and females often postpone leaving home until their second summer, with some individuals never leaving that natal territory, which leads to the establishment of clusters of kin that share space and interact with each other. Thus, the population represents an early stage of sociality.

More recently, behavioral syndromes or consistent individual differences in behavior were examined. Individuals’ responses were recorded in an open arena, particularly their tendency to explore a new environment, as well as responses to a mirror image of themselves and flight responses to a simulated predator. Together, these responses, which fall along a continuum of shy/bold and proactive/reactive personalities, may shed light on decisions made about whether and when to disperse, where to settle, and how to interact with individuals that live nearby. In the last two years, she has discussed various aspects of her research in four articles published in the Journal of Mammalogy.