20 May 2015

Last month brought news of the best-preserved skeleton ever found of a South American Terror Bird.  When Audubon’s Science News compared the fossil to modern birds I made the connection to peregrine falcons.  Can you guess why?

Terror Birds were a genus of large, flightless, predatory birds that thrived in South America from 60 million to 2.5 million years ago.  Found at a coastal cliff in Argentina, the skeleton of Llallawavis scagliai shows he was four feet tall, had a face like a hatchet (literally!) and a low voice like an ostrich. Though he couldn’t fly he could run 60 miles an hour and capture anything he wanted to eat.

He hatcheted his prey with his enormous beak! Click here for an artist’s rendition of what he looked like.

The Terror Birds’ nearest living relative is the seriema, also native to South America.

At three feet tall, seriemas can fly but they prefer to walk and can run at 40 miles an hour when they need to.  They forage on the ground for plants, lizards, frogs, rats and smaller birds and kill large prey by slamming it against the ground and ripping it with their sharp claws.  That snake (above) doesn’t stand a chance.

Seriemas are related to Terror Birds and recent DNA tests have shown that peregrine falcons are closely related to seriemas.  (Click here for their family tree. They’re at the bottom.)

So I wonder … are peregrine falcons descended from the Terror Birds?

If not in body, certainly in spirit!

(photo credits:
Peregrine falcon photo by Chad+Chris Saladin
Skeleton of Llallawavis scagliai linked from the Science Daily; click on the image to read the article
Seriema photo from Wikimedia Commons; click on the image to see the original)