IIRC this theory was debunked some time ago by a study. If you think about it, any dampening within the skull would lessen the force of the pecking and the bird would have to hammer away harder.
Edit: Link to a study
Not trying to contradict the study, but integrated force and impulse are different. You can apply the same force over a longer period of time and lower the impulse. This is why a boxer wearing a glove can actually deliver more total energy without breaking their own hand - the energy transfer is more complete because the greater surface area and longer impulse and more elastic collision. This means that you are more likely to experience a concussion, whereas with a bare fist, broken bones and torn ligaments are more likely to absorb a significant amount of that total energy.
Impulse is the integral of force over time, but I get what you're after.
When pecking at a tree, the maximum force exerted is what pushes the wood beyond its breaking point. That maximum force can be increased by increasing the impact energy as a whole (wasteful and costly) or shortening the impulse. A woodpecker isn't trying to do soft blows to shake some branches, it's trying to shatter a small portion of the trunk, much like someone looking to shatter their opponents nose would choose bare fists over boxing gloves.
He’s an instigator!
Reminds me of a joke I'm going to attempt to translate:
That made me chuckle, thanks for posting it. Kinda reminds me of a joke-phrase in American English that goes "If a frog had wings it wouldn't bump its ass when it hopped."
If my grandmother had wheels she would have been a bike
That's got to feel weird as fuck
Woodpeckers would probably think it feels weird for us to have a tongue that just goes down your throat
Perspective
ayyyy boo, what that tongue do?
Subhanallah.
I mean… tongue bones?
All woodpeckers are just really good at functioning with chronic brain damage.
Nice hair, dude!
And we're all jealous of woody the woodpecker on this glorious summer day.
Oh I thought they'd experience more than 1000 grams of force whilst pecking 😜
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