Project description:Uncovering the genomic regulation of phenotypic adaptation is a major goal in biology, but this has been hard to achieve for complex behavioral traits. Here, we leverage the repeated evolution of obligate cavity-nesting in birds to test the hypothesis that the shared pressure to compete for a limited breeding resource drives convergent behavioral evolution via convergent gene regulatory changes in the brain. Using behavioral assays in the field, hormonal measures, and transcriptome-wide analyses in 10 focal species, we examined females and males in five avian families, each including one obligate cavity-nesting species and a related species with a more flexible nesting strategy. Results support the hypothesis of behavioral convergence, with high levels of territorial aggression in obligate cavity-nesters, particularly among females. Levels of testosterone were not associated with nesting strategy for either sex, but phylogenetic analyses of individual genes and co-regulated gene networks revealed some shared patterns of gene expression, with functional enrichment related to metabolic and mitochondrial processes. Though this gene regulatory convergence may contribute to behavioral convergence, concordance in gene expression did not scale across multiple families. These observations indicate that replicated evolutionary increases in aggression arise via largely lineage-specific changes in brain gene expression.
Project description:RNA-sequencing of the orbitofrontal cortex was performed in male and female rats following exposure to the limited bedding and nesting model of early life adversity.
Project description:The microsporidia Nosema ceranae are intracellular parasites that proliferate in the midgut epithelial cells of honey bees (Apis mellifera). To analyze the pathological effects of those microsporidia, we orally infected honey bee workers 7 days after their emergence. Bees were flash frozen 15 days after the infection. Then, the effects on the gut ventriculi were analyzed and compared to non-infected (control) bees.