[Related: Same-sex mounting in male macaques can help them reproduce more successfully.] “This general question of evolutionary function—that behavior must aid in survival and reproduction ...

Science has treated same-sex sexual behavior as an ... tried to explain why many animals practice a behavior that produces an evolutionary dead end. This has often led to nonadaptive explanations ...

Now, new research suggests there may be an underlying architecture that orders the movements of animals as they go about their very different lives. And it's more widespread than previously imagined.