"Jumping genes" helped ants evolve after the extinction of the dinosaurs

Researchers propose that mobile DNA, known as transposable elements or “jumping genes,” helped ants diversify after the asteroid impact 66 million years ago ended the age of dinosaurs. These DNA sequences can move and multiply within genomes; once viewed mainly as harmful genomic parasites, they are now understood as potential sources of evolutionary change. Comparing genomes from 163 species across 12 ant subfamilies, the team reconstructed transposable-element activity over roughly 100 million years. Ant lineages with more of these elements are generally richer in species today, and the ancestors of the largest ant groups experienced separate bursts of activity in the early Palaeogene, shortly before those groups expanded into thousands of species.

The researchers connect this genomic activity to changes in genes for chemical communication, especially odorant receptors. Ants rely heavily on smell to navigate, identify nestmates and coordinate colony life, so an expanded capacity to detect chemical signals could have helped them adapt and diversify. The findings offer a proposed link between the ecological upheaval following the dinosaur extinction and ants’ later evolutionary success: transposable elements may have contributed both to genetic innovation and to the expansion of traits important for social living. Similar bursts of jumping-gene activity have been associated with periods of diversification in other animal groups, including primates and bats.