Grant: Discovery Grants Program - Individual

The proposed research explores how the features of an organism influence its ability to adapt and to diversify over evolutionary time. Using yeast, we will expose populations of cells to extreme environmental conditions and assess their ability to survive and adapt, allowing us to measure a number of key evolutionary quantities, including the strength of selection, the degree of dominance, and the genome-wide potential for advantageous mutations. Modern genomic tools will then be used to determine the exact genetic changes caused by each mutation, allowing us to determine which genes contribute most often to survival and adaptation to extreme environmental conditions. To study how the features of an organism influence its ability to diversify over longer evolutionary time scales, we are developing new bioinformatic tools that infer the influence of a trait on the rate of speciation and the risk of extinction. These methods are able to use the large number of phylogenetic trees being generated today, coupled with data on character states for the species of interest, to determine the relationship between a character and rates of speciation and extinction. Finally, we seek funding to continue the development of mathematical models that examine the interplay between different evolutionary forces that have shaped the variety of biological systems that exist today. Evolutionary models currently under development include studying interactions between different hypotheses for the evolution of sex and recombination, explaining sex ratio variation when males and females differ in their selective optima, investigating the features of an organism that facilitate the evolutionary transition from free-living to parasitic life cycles, among other on-going theory projects. Altogether, the proposed research offers a multi-pronged approach to revealing how biological systems evolve and how the features of a biological system influence short-term adaptation and long-term speciation and extinction processes. Trainees involved in this research thus develop a variety of skills, including experimental design, microbial techniques, bioinformatics, and mathematical modeling, and have been highly successful in their chosen career paths.