Image credit: jLasWilson | Pixabay
Woodpeckers would make wonderful head-banging heavy metal fans, banging their beaks against trees thousands of times a day in excess of 10 miles an hour. So how come they aren’t permanently concussed?
Impacts over 80-100 g-force tends to be the range that humans start to experience concussions and other forms of brain damage, woodpeckers experience forces 1,000 times that of gravity.
The secret to not being permanently brain damaged lies in the structure of their skull. The bone surrounding the small, smooth brain is spongy, acting as a cushion for the brain. Another bone called the hyoid bone, an attachment for the tongue, extends far back into the skull wrapping around it, sometimes as far as the nasal cavity or eye socket. It is thought that this bone extension acts as a cradle for the skull, reducing shock and rattling.
In addition to this unique cranial morphology, woodpeckers have also developed a membrane covering their eye sometimes compared to a third eyelid. A fraction of a second before impact, this membrane closes over the eye, literally stopping the eyeball from ejecting from the skull with the force of impact, and protecting the eye from any resultant debris. What could be more metal than that?