Mechanisms of Long-Term Monogamous Relationships in Zebra Finches

Cornell University, Ithaca NY

Investigators

Abstract

PI: Elizabeth Adkins-Regan This project will explore the mechanisms of the lifetime pair bond that forms between male and female zebra finches. Biology seeks to explain not only general features of most organisms (fundamental processes of life) but also the diversity in organismal forms and lifestyles. There is great diversity in animal mating systems. This diversity includes interesting variation in whether males and females form long-term close social relationships in order to reproduce. Long-term monogamous relationships, including pairing for the life of the animals, are scattered throughout the animal world (including some human populations) but are most common in birds. This kind of mating system is poorly understood. The objective of this research is to explain the function (how such relationships lead to better reproduction) and the physiology responsible for the formation and maintenance of these relationships using a species, the zebra finch, that pairs for life. The research will answer questions such as: are the birds more reproductively successful if they continue with the same partner rather than choose a new partner? Are sex hormone actions required for birds to pair and to remain paired? Do pubertal sex hormones have any long-term effect on pairing? Are they responsible for the transition from attachment to the parents to attachment to the pairing partner? What is the role of the physiological stress response following separation of the pair in re-pairing following loss of the partner? Are physiological changes following separation part of the costs that normally prevent separation? The methods will include hormonal and social manipulations during juvenile development and adulthood, behavioral testing designed to measure pairing preference and status, and determination of reproductive success and hormone levels. By discovering what is responsible for pairing and remaining together, this research will answer important questions and will offer and test new hypotheses about the physiology of ecologically relevant behavior applicable to a broad array of socially monogamous animals. The research will also provide valuable training and an important start to a scientific career for a large number of undergraduate and graduate students of both genders and of diverse backgrounds and origins.