Owls!

Owls are the most flexible creature including humans due to the fact that owls head is connected with single socket pivot. Hence, owls can rotate 270 degrees whereas people are limited because of the presence of double socket pivot thus limit them to twist as per the research. Though the presence of multiple vertebrae the connector between the brain and the spin give them a wide motion range. With such a soft body, it is difficult for a bird to withstand such tremendous pressure of movement, humans life may come to end due to an extreme level of internal bleeding because of breakage of nerves.

For further reference go through the article attached below:

Research behind Owls twisting it head 270 degrees

Hope you find it amazing to know it!

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