I am broadly interested in understanding the role of hybridization in evolutionary processes. Hybridization is a common evolutionary process that can have major impacts on adaptation and speciation. Despite the fact that hybrid populations are common, we currently know little about how these populations change over time, except in the rare cases where hybrids themselves become reproductively isolated ("hybrid speciation"). One of my current focuses is understanding how selection shapes the genomes of hybrids over many generations.
I am also interested in what we can learn about reproductive isolation and speciation from studying hybrid populations. Hybrids often suffer from reduced viability or fertility due to negative interactions between mutations that have accumulated between the two parental genomes since speciation. Hybrid populations can be used to identify these incompatibilities and help us understand the architecture of genetic barriers between species.
We can also use hybrid populations to map to genetic basis of traits that are important in distinguishing species. I am particularly interested in understanding the genetic basis of sexually selected traits because these traits are important in preventing hybridization.
My empirical work focuses on the swordtail fish group Xiphophorus. This group is an excellent model system for understanding both hybridization and the evolution of sexually selected traits. Xiphophorus species have remarkable morphological and behavioral diversity, in part driven by sexual selection. Strong behavioral premating isolation prevents hybridization in many species, but we have found that hybridization is incredibly common in Xiphophorus, perhaps due to the fact that behavioral premating barriers are prone to disruption in changing environmental or ecological conditions.
© Copyright 2012- Molly Schumer