In many animal species males and females differ in appearance and behavior and these differences usually arise about the time of puberty, when extensive hormone changes occur. However, there is no theoretical reason why differences cannot develop earlier in life as long as the advantages of the differences are expressed later, as adults, in gaining reproductive mates. Nevertheless, this early expression of differences (and the later advantages) has not been the subject of much study. In one excellent case, hatchling male collared lizards that are setting up their territories develop a bright color signal and treat other hatchling males aggressively and hatchling females non-aggressively. These young males begin to pair bond with young females as future mates and repel young males as future mate rivals. This study uses biochemical, genetic, molecular, and field approaches to document the hormones responsible for the development of the early sexual differences in this species, and the genetic advantages expressed later in life. This species is a model for the study of this phenomenon, and results should apply broadly, even to humans. The research should spur more investigation of early male-female differentiation and plant a paradigm shift in evolutionary ecology.
Both graduate and undergraduate students will take part in this research and especially Native Americans will be recruited to learn how science is done and communicated. Undergraduates will be individually mentored through all stages of the research, including presentation of results at public conferences. Results will be published in scientific and lay outlets, including magazines, newspapers, television, and the internet. Data will be available at the Oklahoma PetaStore (http://oscer.ou.edu/petastore.php), free to all academic users, and readable results and significance on a webpage accessed from the main public webpage of the Department of Zoology at Oklahoma State University (http://zoology.okstate.edu/).
