How Does an Owl Rotate Its Neck Almost Full Circle?

Hoo wants to know? Owl tell ya!

A study published in the Science journal found that blood vessels at the base of owls' heads are able to balloon outwards when blood flow increases.

This enables them to create "reservoirs" of blood which are needed to supply the animals' out-of-proportion heads and eyes while their heads are turned, researchers explained.

In contrast, humans' arteries tend to decrease in size and do not swell to accommodate greater blood flow, creating the risk of clotting after sudden neck movements such as whiplash or botched chiropractic therapy.

Owls were also found to have especially large cavities in their neck vertebrae through which arteries pass, leaving extra space for movement when the neck is twisted, and to have small connections between the carotid and vertebral arteries which allowed blood to pass from one to the other in the case of one becoming blocked during extreme neck rotation.

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