DISSERTATION RESEARCH: The Maintenance of Cooperative Nest Construction in Sociable Weavers (Philetairus Socius)

University Of Miami, Coral Gables FL

Investigators

Abstract

Although evolution by natural selection has often been depicted as favoring ruthless, selfish behavior, cooperation is actually widespread in nature. Consequently, the evolution of cooperative behavior has become a central problem in biology. The present research examines the evolution of a particular form of cooperation, cooperative nest building in an African bird. Communal nests represent a public goods dilemma: each individual benefits directly from the communal nest, but would benefit more if it could refrain from contributing to nest-building as long as others continued to maintain the nest. Such public goods dilemmas are common in human societies but have rarely been explored in non-human animals. This research will investigate cooperative nest construction behavior of a Namibian bird, the sociable weaver. Observations of nest construction in nature will examine relative contributions of the sexes and of individuals to test whether cooperation in this instance can be explained via kin selection. Simply, kin selection is a type of natural selection favoring aid to genetic relatives. An agent-based model will be used to further explore the possibility that cooperative nest building can be sustained through kin selection. The computer code used to implement the model will be made available to other scientists, thus facilitating future modeling efforts in social evolution. In addition, an experiment will test whether individuals that forego cooperative nest construction are punished by others; such punishment is a common explanation for contribution to public goods in human societies. Thus the research will test whether theories explaining contribution to public goods in human societies explain cooperation in this model system. The project will also contribute to the development of the next generation of scientists and engineers. The project includes undergraduate mentoring and training in genetic analyses and behavioral observation, thus providing useful research experience for the next generation of American scientists.