The owl's head can rotate greatly. How is this done? Do you know why?

Speaking of owls, many people think that they have big heads and round eyes, but you may not know that they also have a special function, that is, they can rotate their heads 270 degrees. ...

If this is a human, there will only be a "click" on the neck. Today, I will talk about the amazing body structure of owls.

Owls originally belong to birds, ranging in size from 90 cm to less than 20 cm in length, such as carved owls.

Because of its panel and ear feathers, this bird's head is very similar to that of a cat, so this bird is commonly known as an owl.

One of the greatest characteristics of owl is its unique turning skills. Sometimes it looks like a turn of 360, but it is actually a turn of 270.

In fact, the owl had to turn around. To be exact, it was hurt by its eyes.

Owl's eyes are really big, and the weight of a single eye can account for 1% to 5% of their weight, but its eyes are not round, but the exposed cornea looks round, and the eyes are actually tubular.

If you don't believe me, you can open the owl's ears, and you can see the tubular sclera around your eyes.

If you look closely, you will find that the owl's eyeball can't move freely like humans, because of this structure in the orbit-scleral ring.

The role of scleral ring is to prevent the eye injury caused by high-speed airflow when an owl swoops down on its prey, but it also limits the eye movement.

Therefore, if an owl wants to judge its surroundings better, it needs flexible neck movements.

When the head rotates 270, the internal structure of the owl's neck bone is of course very special.

Our human cervical vertebra is seven bones, and the owl can reach 14 joints, which can accommodate a little more rotation of each joint, so that it can rotate at a larger angle.

In addition, a study by Johns Hopkins University also found that there is a blood bank in the owl's head, and the closer it is to the top of the neck, the larger the vertebral artery.

This allows owls to temporarily replenish blood to their brains even when their necks are extremely twisted.

The transverse foramen of human cervical vertebra, the carotid artery will pass through the transverse foramen. Because the diameter of transverse foramen is very small, blood vessels almost fill the whole cavity. If the head rotates at a large angle, human blood vessels will rupture.

Like humans, the carotid artery of owls passes through the spinal canal.

But the difference is that the diameter of the transverse process hole of the owl's cervical vertebra is about ten times larger than that of human beings, which makes the owl's blood vessels swing greatly.

Even if you turn your head sharply, you can protect blood vessels from the oppression of bones. The general rule of human arteries is that the farther away from the heart, the smaller it will be.

This is why the owl's head can rotate 270 degrees, while our head can only rotate about 90 degrees.