Collaborative Research: Phylogenetics, hybridization and speciation in Habronattus jumping spiders (Saliticidae)

San Diego State University Foundation, San Diego CA

Investigators

Abstract

One of the major goals in biological research is to understand the processes that generate different species. Recently, biologists have suggested that the sharing of genes and traits between different species (hybridization) may play an important, but overlooked role. If true, this not only calls into question our understanding of how species form, but changes how we evaluate the relationships between species. In this project, researchers from San Diego State University and UC Berkeley will link studies of phylogeny and behavior to understand the role of hybridization in the evolution of a large genus of jumping spiders (Habronattus) from North America. The team will develop genomic resources to reconstruct the evolutionary relationships between species and to statistically test for the presence of hybridization in driving biodiversity patterns. Additionally, because hybridization occurs only when individuals of different species mate with each other, the team will examine the mating behaviors that control the exchange of genes and traits between separate species thus allowing insight into the mechanisms that drive larger evolutionary patterns. This project will advance our understanding of how species and populations of animals change and how we evaluate their evolutionary relationships. Research findings and techniques will be used to develop freely available statistical tools for scientists, online biodiversity databases, and educational spider-centric computer games to teach key aspects of systematic biology, in particular sexual selection and speciation. Two postdocs, one doctoral student, and multiple undergraduate students at three separate U.S. institutions will be trained on this project. Undergraduate students will play important roles in research, with high potential for independent projects. This research will advance Habronattus research, and the field of introgressive hybridization biology, in multiple ways. At both phylogenomic and phylogeographic scales the researchers will quantify the balance between tree-like divergence and reticulate evolution, addressing whether phenotypic evolution is better explained by introgressive hybridization rather than a tree-based model. Phylogenetic comparative analyses will be conducted to ask whether courtship complexity is correlated with rates of lineage diversification, introgression, and chromosome evolution. Finding widespread introgression concentrated in groups with the most complex courtship would contradict expectations of animal communication theory. Genomic-scale data will provide a consistent, objective framework for interpreting species limits, unbiased by male ornament "conspicuousness". At the behavioral level, the researchers will address the proximate mechanisms behind introgressive hybridization, addressing whether hybridization is best explained by errors in species recognition or selection for novel phenotypes. Large empirical genomic and phenotypic datasets will promote the development of new computer program modules to map phenotypic characters impacted by introgressive hybridization or incomplete lineage sorting. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.