Hybridization between these species is remarkable across vertebrate species, as such events typically occur between recently diverged populations, whereas the most recent common ancestor to blue (Cyanocitta cristata) and green (Cyanocorax yncas) jays is estimated to have lived at least 7 million years ago. A male hybrid of a green jay mother and a blue jay father. Image credit: Brian R. Stokes. “We think it’s the first observed vertebrate that’s...
