We tend to view sexual selection as secondary to natural selection, but nothing is second to the imperative to reproduce. Sometimes that means that even precisely engineered traits like echolocation have room to be a little sexier. Could falsetto calls really be a signal of male quality in the Mehelyi's horseshoe bat?
The orb-weaving spiders build webs so spectacular and bizarre that it seemed they must also be one-of-a-kind. As Tauana Junqueira Cunha explains, modern phylogenetic techniques have now unraveled a tangled web of data to reveal the true story.
You might have thought eusociality, an extreme form of cooperation that makes a colony of individuals verge on a superorganism, was just for ants and bees. As we learn more natural history, though, we see more and more examples. Here, Jack Boyle explains how scientists created artificial nests so they could observe the social habits of X. saxesenii, an ambrosia beetle normally concealed in tree trunks, to determine whether they meet the three eusociality criteria.