Owls have a narrow field of vision, and their eyes don't move much. This limitation is addressed with an extraordinary adaption: they can rotate their heads up to 270 degrees without damaging their blood vessels.
They can do that because their necks have 14 vertebrae (humans have seven). But it's really the way the animal manages the flow of oxygenated blood to its brain that underpins the impressive feat. Their big carotid arteries, instead of being on the side of the neck as in humans, are carried close to the center of rotation just in front of the spine. Because of this, these arteries experience much less twisting and stretching and the potential for damage is therefore greatly reduced. Read more at the source: www.bbc.com/news/science-envi...