Structures and behaviors used in mating tend to evolve more rapidly than other features. One explanation for this pattern is that the sexes are engaged in a perpetual "arms race" in which males and females vie for control over the investment each makes toward reproduction. Collaborators Shultz and Hedin will test the sexual-conflict hypothesis in harvestmen or daddy long-legs. They will lead an international team to reconstruct the evolutionary relationships among 90 species using molecular sequence data. The resulting phylogenetic tree will be the first for these animals and will be used to determine the timing and direction of evolutionary changes in reproductive features. Statistical tests will determine whether evolutionary patterns are consistent with a sexual arms race in which antagonistic features of one sex promote the evolution of defensive or antagonistic features in the other.
The project will generate much-needed data for addressing on-going controversies about the evolutionary mechanisms underlying rapid diversification of reproductive features. In addition, the project will fund 30 children from low-income families in the Washington DC area to participate in a summer day camp at the University of Maryland. Campers are introduced to the diversity and scientific study of insects and other arthropods. The project will also train graduate students in systematics and evolutionary biology at the University of Maryland and San Diego State University.
