In what researchers call a "biological annihilation," human activities are driving entire groupings of vertebrate species to extinction at a rate 35 times what it would have been without human interference.Monday, found that 73 genera—the next thickest branch from species on tree of life—had been lost since A.D. 1500.
Previous attempts to grapple with the sixth mass extinction had focused on the number of species lost or at risk. But looking at genera can provide a clear view of the "magnitude and impact" of these losses, the study authors wrote.