Planet Earth

Study: Breathing Like a Bird Helped Dino Ancestors Rise to Power

80beatsBy Andrew MosemanJan 14, 2010 11:25 PM
alligator-lungs.jpg

Newsletter

Sign up for our email newsletter for the latest science news
 

Alligators breathe like birds, with a one-way tube that flows all the way through their respiratory systems. While that might not seem earth-shattering at first, alligators and birds diverged 246 million years ago. And according to a new study in Science, that means this breathing technique goes way, way back, and could even explain how the ancestors of dinosaurs survived the great Permian-Triassic extinction.

Unlike a mammal’s breath, which exits the lungs from the same dead-end chambers it enters, a bird’s breath takes a loopy one-way street through its lungs [Science News]

. This breathing technique allows birds to explore high altitudes where oxygen levels drop off significantly. If the archosaurs—ancestors to birds and alligators—breathed this way, it could have given them an advantage when oxygen level tanked 250 million years ago and lots of species died off.

Before the extinction, synapsids, the ancestors to modern mammals, were the dominant group. But after the extinction, the archosaurs dwarfed the synapsids, Farmer said. Prestosuchids, for example, could reach 23 feet in length, while mammals’ ancestors maxed out at just a few feet [Wired.com]

. One burning question remains, though: How the heck did we miss this for so long?

“People incorrectly believe that you must have avian-style air sacs in order to have unidirectional flow,” says C.G. Farmer of the University of Utah, a coauthor of the new study. “Alligators don’t have air sacs, so no one ever looked” [Science News]

. But there it was, hiding in plain sight—presuming you have the stomach to study alligator lungs. Related Links: 80beats: New Fossil Suggests Dinosaur World Domination Started in South America 80beats: Found: Dino-Munching Crocodiles Who Swam in the Sahara 80beats: Extinct Goat Tried Out Reptilian, Cold-Blooded Living (It Didn't Work) 80beats: Dinosaurs Ruled the World Because They "Got Lucky," Say Scientists

Image: C.G. Farmer, Science/AAAS

1 free article left
Want More? Get unlimited access for as low as $1.99/month

Already a subscriber?

Register or Log In

1 free articleSubscribe
Magazine Examples
Want more?

Keep reading for as low as $1.99!

Subscribe

Already a subscriber?

Register or Log In

More From Discover
Recommendations From Our Store
Shop Now
Stay Curious
Join
Our List

Sign up for our weekly science updates.

 
Subscribe
To The Magazine

Save up to 70% off the cover price when you subscribe to Discover magazine.

Copyright © 2021 Kalmbach Media Co.