By Alec Jennings
University News Service
September 13, 2010
A three-year, $350,000 National Science Foundation grant was awarded to three Texas State University-San Marcos Department of Biology faculty members to study the evolutionary paradox inherent in unisexual species' reproduction.
The project: "The maintenance of unisexuality: behavior, hormones, and genetic diversity in a unisexual-bisexual mating complex," will be conducted by Caitlin Gabor, associate professor, Department of Biology, Andrea Aspbury, senior lecturer, Department of Biology and Chris Nice, associate professor, Department of Biology.
Gabor said the study will look at a special kind of unisexual species—all female, gynogenetic—of hybrid origin that require mating from their parental species to start the development of their eggs but do not fertilize their eggs. This presents an evolutionary paradox because the species do not benefit from the increase in genetic variation that occurs in species that reproduce sexually.
"The project will provide information about how complex interactions between species influence the evolution of reproductive strategies," Gabor said. "This research addresses hypotheses about maintenance of unisexuals, in a mating system consisting of the live-bearing gynogenetic fish, the Amazon molly, and its parental species (hosts), the sailfin molly and the Atlantic molly."
The researchers will investigate how hormone levels in male host species and the abundance of Amazons affect the propensity of males to mis-mate. They will also examine the number of times the clonal Amazon molly originated and test if extinction and colonization of inter-connected populations explains the maintenance of Amazons.
"The interesting nature of this system makes it appealing for K-12 and college students," Gabor said. "This work will include participation by students at all levels, including underrepresented groups in evolutionary biology. Students and the principle investigators will give talks and provide activities about these studies."
The National Science Foundation (NSF) is an independent federal agency created by Congress in 1950 "to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense." With an annual budget of about $6.9 billion, they are the funding source for approximately 20 percent of all federally supported basic research conducted by America's colleges and universities. In many fields such as mathematics, computer science and the social sciences, NSF is the major source of federal backing.