Owls are known for their ability to turn their heads “All the way around”, but have you ever wondered why?
Owl perching by Peter Trimming
Well first off, contrary to popular belief, owls are not able to turn their heads the full 360 degrees. Most owl species, but not all, can turn their heads up to 270 degrees. The reason why they have adapted this ability is thought to be linked to the fact that unlike humans, with movable oval eyes, owls have tube like eyes that do not have the ability to swivel much.
If a human snapped their neck at the speed and angle that owls are able to do, there would be severe trauma to the neck and arteries, or completely stopping the blood flow to the brain. To test how this works, researchers, led by Fabian de Kok-Mercado, injected dye into the blood stream of dozens of owls, and used a CT scan to track the flow of dye throughout the bloodstreams of the owls.
After the CT scans were completed, they then injected a plastic like substance into the blood stream, let it harden, then dissected the owls to find out how the arteries were oriented.
Northern spotted owl by user USFS Region 5
Via Flickr
It was found that the owls neck bones, or vertebrae, contain holes that are much larger than those found in humans. In humans, the holes are just about as big as the arteries, whereas in owls they are about 10 times larger. These likely contain air sacks meant to cushion the twisting motion of the neck. This may explain why the blood vessels do not break during the rapid head turning motions of the owls.
The researchers also noticed that the artery slightly enlarges as it gets closer to the head. This is thought to allow blood to pool so that the brain has extra blood to work with as the head swivles.
Above is a video explaining the details of how owls are able to turn their heads up to 270 degrees. [By user SciFri via Youtube]
And there you have it, the science behind how owls can turn their head at great angles. Wouldn’t that be cool if humans can do that to?
…
Okay, maybe not. Lets leave this to the owls.
-Christina Bell
