Newts defend themselves from predators such as snakes by secreting a potent nerve poison, tetrodotoxin (TTX), but some populations and species of garter snakes have evolved resistance to TTX. The molecular mechanism for this resistance is known, as is one of the genes involved, providing an excellent opportunity to investigate the evolutionary genetics of a trait that has a clear adaptive value. The studies will include a survey of the genetic differences underlying the variation in resistance to TTX in different populations and species of garter snakes and a molecular genetic evaluation of the role of natural selection in the evolution of resistance. Several factors could underlie the presence of resistance in multiple populations. These are multiple episodes of independent evolution, spread across populations, or shared ancestry; these alternatives will be tested with molecular genetic analyses. The research will result in disentangling the role of novel mutations, recombination, and gene flow in explaining the geographic patterns of phenotypic diversity.
This project will help to support graduate and undergraduate education in behavioral and molecular genetics. The PIs will promote the participation of minorities and women in science careers through the Utash State University NSF ADVANCE program, the USU Multicultural Research Fellowship Program, and the Mountain Lake Biological Station REU program. The snake-newt system will continue to be developed as a model to illustrate the evolutionary process to the general public through outreach education (similar to the recent PBS-TV material and articles in popular media) and exhibits in museums.
