Spermatogenesis & sex chromosome evolution




Evolution of cryptic female choice


Postcopulatory sexual selection & speciation

Reproductive barriers from gametogenesis to fertilization

Reproduction is a principal element of life. It is the medium of evolution, a source of morphological diversity and a critical aspect of human health. Research in the Larson Lab provides a unique evolutionary perspective on reproduction; we combine speciation, reproductive and developmental biology and behavioral ecology to understand divergence in key traits spanning the complex stages of reproduction. We use this framework to disentangle how sperm development and postcopulatory interactions translate to reproductive barriers that prevent fertilization (postmating prezygotic barriers) or affect the fertility of hybrids (postzygotic barriers). Much of this work focuses on recently diverged species that form hybrid zones.

Hybrid zones: Windows on evolutionary process

Hybrid zones are windows on evolutionary process, but each window opens on a different landscape. Evolutionary biologists have peered through many windows, but only in a few cases have they done more than crudely sketch the scene outside.
— Richard G. Harrison, Oxford Surveys, 1990, pg. 117

As you walk across a hybrid zone you can see the transition from one specie's range to the other and evolutionary processes, such as hybridization, happen right before your eyes. Generations of  recombination shuffle genomes, allowing us to directly link genotype, phenotype and evolutionary processes driving divergence in natural populations. Our research focuses on species in the early stages of divergence that interact in natural hybrids zones. 


Harrison RG and EL Larson. 2016. Heterogenous genome divergence, differential introgression, and the origin and structure of hybrid zones. Molecular Ecology 25: 2454 - 2466.   [Special Issue: Genomics of Hybridization]   PDF

Harrison, RG and EL Larson. 2014. Hybridization, introgression and the nature of species boundaries. Journal of Heredity 105: 795-809.   PDF