Why Don't Woodpeckers Get Brain Damage?

Have you ever seen a woodpecker hammering away at a tree? The constant sound can be awe-inducing or annoying, depending on what you are doing at the time. These repeated motions may seem weird to you, but for these birds it’s a way of life.

A red-bellied woodpecker. (Photo courtesy of Daniel Peterson)

Woodpeckers hammer on structures for several reasons. Repetitive pecking called drumming can be used to mark their territory or find a mate. They also peck as a way to build a cavity in a tree or wooden structure for a nest or roosting spot. And sometimes they're pecking at wood to get at insects, seeds and other foods, or to make a place to store their food.


So how are they able to do it without suffering brain damage or at least a bad headache? Because woodpeckers are built to withstand the physical stress of all that pecking.

To start with, woodpeckers have very small brains. They only weigh 0.07 ounces, which is less than a penny! Bigger brains have more mass, which increases the risk of brain damage. Having such small brains protects them.


The design of their skulls is also helpful. The frontal bones of their skulls work together with a pair of muscles at the base of their bills to act as a shock absorber. The outside of their skulls is made up of dense bone, and the inside is more porous. When woodpeckers are pecking, the force is spread all around the skull, which helps keep pressure off the brain.


Their brains are a tight fit inside their skulls, so they don't move around very much. They also sit at an angle, which creates more surface area to absorb the force of all the pecking. One final part of their bone structure that helps protect their brains is a bone called the hyoid. This bone wraps around their skulls, kind of like a seat belt that protects their brains.


The design of their bills also helps, because the upper bill is longer than the lower bill, and the lower bill is made of stronger bone that is better at absorbing impact.


Even knowing about all the features that allow woodpeckers to hammer away, the sheer nature of their behavior is impressive. The force of each peck can be more than 20 times greater than what can cause a concussion in a human. And they peck an average of 12,000 times a day, moving their heads at speeds of 13 mph to 15 mph.


Woodpeckers’ ability to peck away without harming themselves has even inspired designs to help humans. Several athletic gear companies have created helmets and neck collars based on woodpeckers’ special features.


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