Evolution Is Amazing: Oilbirds

Okay, a fruit-eating, nocturnal, cave-dwelling, echo-locating bird whose calls sound like a man being tortured. Nothing to see here; move along.

Evolution has some ‘splainin to do.

Oilbirds – the species’ hatchlings are heavier and fattier than a full-grown adult, and were rendered for oil on occasion; hence the common name – are distant cousins of Nightjars, the crepuscular/nocturnal insect eating birds like the Common Nighthawk. But the Oilbirds split off from the Nightjars a long time ago. A really long time ago, in the early Eocene. More than 50 million years ago. A fossil Oilbird was found in the Green River Formation in Wyoming. That also suggests that Oilbirds were widely dispersed in earlier days; today they are confined to the northern half of South America.

Oilbirds are so unique they are the only living member of the family Steatornihidae…