A research team from the University of Washington and the Complutense University of Madrid has identified a new fossil species, Galanthis baskini, which pushes back the known evolutionary history of the weasel family by millions of years. The fossilized jawbones were found in the Teruel area of Aragón, Spain, and date to the late Miocene, approximately 6.5 million years ago.
Previously, the oldest known members of the Mustelinae subfamily dated to the Pliocene epoch, about 3.5 million years ago. This discovery effectively doubles the lineage's history. G. baskini was roughly the size of the modern least weasel, and micro-CT scans of its teeth confirm its role as a specialized carnivore, marking the earliest known origin of the modern weasel lineage.