Estrogen receptor α polymorphism in a species with alternative behavioral phenotypes

• Authors: Brent M. Horton, Emory University; William H. Hudson, Emory University; Eric Ortlund, Emory University; Sandra Shirk, Emory University; James W. Thomas, National Institutes of Health; Emily R. Young, Georgia Institute of Technology; Wendy M. Zinzow-Kramer, Emory University; Donna Maney, Emory University
• Journal Title: Proceedings of the National Academy of Sciences
• Volume: Volume 111, Number 4
• Publisher: National Academy of Sciences | 2014-01-28, Pages 1443-1448
• Type of Work: Article | Post-print: After Peer Review
• Publisher DOI: http://doi.org/10.1073/pnas.1317165111
• Keywords: estradiol; testosterone; morph; reproductive tactics

Abstract

Significance In this series of studies, we provide a rare illustration of how a chromosomal polymorphism has affected overt social behavior in a vertebrate. White-throated sparrows occur in two alternative phenotypes, or morphs, distinguished by a chromosomal rearrangement. That the morphs differ in territorial and parental behavior has been known for decades, but how the rearrangement affects behavior is not understood. Here we show that genetic differentiation between the morphs affects the transcription of a gene well known to be involved in social behavior. We then show that in a free-living population, the neural expression of this gene predicts both territorial and parental behavior. We hypothesize that this mechanism has played a causal role in the evolution of alternative life-history strategies.