Old German Owl (left) and Racing Homer (right) domestic pigeon breeds that the researchers bred for the study. Credit must be given to the creator. Only noncommercial uses of the work are permitted.

Charles Darwin bred pigeons, and used them to learn more about the inheritance of different characteristics. For pigeons, beak size is one of those characteristics. There are 350 pigeon breeds or more ...

image: This shows striking variation between breeds of domestic pigeons. Left: Old German owl breed with a head crest and short beak. Right: Scandaroon breed with large beak and no crest. Background: ...