Saturday, April 5, 2014

Pied-billed Grebe

This Pied-billed Grebe kept a close eye on the alligator at The Aransas National Wildlife Refuge on 19 February 2014. I have made several previous posts on this species, which can be accessed through this link.

Grebes are among the most ancient living birds. The oldest fossils are from Chile and are about 80 million years old (Cretaceous). Now grebes are found around the world, but the family is most diverse in South America. Half of the world’s 22 grebes are found in the neotropics.

Grebes were recently thought to be closely related to loons. DNA studies, however, conclude that the two families, due to convergent evolution, are only superficially similar. Today grebes are thought to belong to the same lineage that led to storks, shearwaters, pelicans, and penguins. The origins of loons, however, are more puzzling to ornithologists. Loons may be more closely related to gulls or auks (Handbook of the Birds of the World—Alive).

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