Opposing behavioral roles for a single gene in a species with a supergene polymorphism

expression in a pro-aggression cell population in the anterior hypothalamus positively predicted territorial singing, whereas expression in a pro-parental cell population in the infundibular nucleus positively predicted parental provisioning. Expression in these two regions was negatively correlated, consistent with opposing behavioral roles. Allele-specific analyses revealed stronger expression bias toward the supergene-associated allele in the anterior hypothalamus than in the infundibular nucleus. These findings suggest that chromosomal inversions can support opposing behavioral phenotypes not only by linking multiple genes, but also by driving regulatory divergence of individual genes that organize behavioral trade-offs.