People typically think of the city-sized Chicxulub asteroid’s devastating collision with North America 66 million years ago as simply a mass extinction event—which, of course, it was for dinosaurs. But a growing body of research is making the case that the pall of death and darkness left worldwide in Chicxulub’s wake proved to be a boon not just for tinier scurrying mammals but also for giant fungi, exotic deep-sea lifeforms, and now the sprawling colonization of Earth by ant kind.

Today, over 15,000 species of ants dot the globe, their queens ruling over a vast empire hidden underground (and also within dead trees or other suitable venues). Evolutionary biologists and genomics researchers, collaborating between Germany, China, and Denmark, have now identified several independent bursts in ant species’ diversification dating back to the early Paleogene just after Chicxulub hit. Their new study attributes ants’ biodiversity boom to retrovirus-like transposable elements of DNA, sometimes called “jumping genes.”

“The asteroid impact had dramatic consequences for the environment,” the study’s lead author, Lukas Schrader, a professor of molecular evolutionary biology at Germany’s University of Münster, said in a statement. “We have now found the genomic mechanism that connects these ecological upheavals to the subsequent rapid diversification of the ants: transposable elements.”

Scientists used to think of transposable elements (TEs) as effectively “genomic parasites,” given this DNA’s tendency to spread from host to host, seemingly as an end unto itself, without offering any clear evolutionary advantages. Some TEs, studies have shown, are even suspected of contributing to diseases themselves, including some cancers and neurological disorders.

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