6th Annual Symposium
November 14 - 16, 2008
in Kansas City
Click here for details!

Evolution and Genomics/Proteomics of Adaptive Phenotypes

In the broadest sense, research in my laboratory focuses on the evolution of adaptive phenotypes – including traits related to fertilization success, behavior, and responses to environmental cues. We utilize a range of behavioral, ecological, and genetic/genomic /proteomic techniques to investigate these phenotypes and the processes that underlie their evolution. Currently, we have research on-going in the two areas outlined below.

Speciation and the rapid evolution of barriers to fertilization in crickets
     The Allonemobius socius complex of crickets consists of three species
that have evolved from a common ancestor over the past 30,000 years.
Parental genotypes are maintained within two separate hybrid zones
(each involving different species pairs) even though the only barriers to
gene exchange appear to be traits related to fertilization (e.g., female
reproductive tract morphology and male accessory gland proteins).
Specifically, there are both competitive (conspecific sperm precedence)
and non-competitive (a male’s ability to induce a female to lay eggs) gametic
isolating barriers between these three species. These gametic isolation
phenotypes are associated with species boundaries and evolving rapidly.
Our current work is focusing on (1) identifying the molecular basis of these
phenotypes, (2) determining how the underlying genes are evolving, and
(3) studying/identifying phenotypes associated with male-female sexual conflict.

Molecular evolution and the genomics of adaptive phenotypes in aphids

     In collaboration with Jerry Reeck (Department of Biochemistry) and John Reese (Department of Entomology), we are identifying the genes that underlie survival on plants, behavior, and host-plant specificity in a diverse array of aphid species. With the availability of the pea aphid genome, large tissue-specific EST libraries, and a RNAi protocol developed here at KSU, a wide range of the functional genomics questions can be addressed – including the evolution of sex and host-race formation. Currently, we are investigating the molecular evolution of genes linked to feeding and survival on plants. This includes analyses of dN/dS ratios, RNAi experiments, and reverse-genetic experiments to identify the phenotypes of positively selected genes.