BirdNote: Birds Are Evolving Rapidly - Today
House Finches are evolving rapidly and visibly. In 1941, some captive House Finches from California escaped near NYC. They spread rapidly and are now found across most of the US.
We know the finches have evolved, because those that survive differ from their parents. Size is one example.
Male House Finches in recently established populations are larger than the males that escaped. Females have become smaller and survive better than larger females as nestlings. Evolutionary changes are occurring visibly all around us.