The bird that wears its tongue as a helmet

When a woodpecker hammers a tree, its head travels at 15 miles per hour, experiencing a deceleration of 1,200g. A human would suffer a fatal concussion at just 100g.

To survive, the woodpecker uses a tongue that is three times the length of its beak. Instead of sitting in the mouth, the tongue extends backward, exits the lower jaw, and loops entirely around the back of the skull.

The tongue acts like a biological seatbelt. In the milliseconds before the beak makes contact, the bird tightens these muscles, bracing the brain against the skull and distributing the shock of the impact.

The bird also possesses a sponge-like bone at the front of its skull that absorbs the remaining vibration. Its eyelids shut tight immediately before each strike to prevent its eyeballs from popping out of their sockets from the pressure.

Since the bird strikes the tree up to 20 times per second, this entire bracing system must engage and disengage at a blinding speed.

Interestingly, the tip of this massive tongue is often covered in barbs and sticky saliva, allowing the bird to reach deep into insect tunnels once its 'helmet' has finished doing its job.