Meeting Abstract
The neural transcriptome is closely tied to behavior. Still, high variability of gene expression – even among members of the same population – poses a challenge for linking expression patterns with specific behavioral outputs. Phylogenetic comparative methods provide a powerful tool to identify molecular pathways repeatedly associated with similar phenotypes across species. Combined with the ever-increasing accessibility of transcriptomes obtained from diverse species, comparisons of neural transcriptomes across species can serve as natural experiment to test evolutionary hypotheses of behavioral evolution. However, phylogenetic relatedness can confound associations between expression and phenotypes and appropriate, phylogenetically-informed transcriptomic analyses are still debated. Here, we take a comparative transcriptomic approach to identify neuromolecular correlates of a fascinating example of interspecific cooperation, cleaning behavior in coral reef wrasses. Multiple species of Labridae wrasses have independently evolved cleaning behavior, where cleaners remove ectoparasites, mucus, and damaged tissue from larger, often predatory “client” fish. We combine multiple comparative approaches with standard transcriptomic analyses including differential gene expression and dimensionality reduction to compare the forebrain transcriptomes of six wrasse species. We characterize neural gene expression diversification across species and identify robust correlates of cleaning behavior and other behavioral and ecological phenotypes. Our results provide insights into the evolution of the neuromolecular basis of cooperative behavior.
