Ancient Bees May Have Been Wiped Out with the Dinosaurs

Carpenter bee

The ancestors of modern carpenter bees may have vanished from Earth roughly 65 million years ago, around the same time the dinosaurs were wiped out, a new study finds. Researchers examined the DNA of four types of carpenter bees — belonging to the group Xylocopinae — from every continent, except Antarctica, to search for clues about their evolutionary relationships. Peering back into the lineages of the bees, the scientists noticed something unusual with all four groups, beginning roughly 65 million years ago, at the boundary between the Cretaceous and Paleogene periods. "We can track periods of diversification and stasis," lead study author Sandra Rehan, an assistant professor of biological sciences at the University of New Hampshire,told LiveScience. "There was a period where there was no genetic diversification happening for millions of years — a real dearth of speciation. This is an indication of a mass extinction event." The end of the Cretaceous Period, corresponding to the beginning of the Paleogene Period, was already known to be a dynamic time in history. It is commonly thought that a massive asteroid or comet slammed into Earth 65 million years ago, wiping out the dinosaurs and killing up to 80 percent of all species. "We found this mass extinction event signature in the DNA that just happened to correspond to the extinction of dinosaurs, which was a major change in the global diversity at the time," Rehan said...more