Happy Thought for 28 March 2024

Have a Happy Thought:

 You know when you feel the need to bang your head against a wall, or a desk? But you’re afraid of giving yourself a concussion?

 Well, maybe (?) we have things to learn from woodpeckers.

 Great Spotted Woodpecker (Dendrocopos major) in Scotland.

Image: Gary Zambonini https://creativecommons.org/licenses/by-sa/2.0

 

Side comment: the Latin name for the Great Spotted Woodpecker, Dendrocopos major, effectively translates to “big wood-pain”. Which is a mood.

Side-side comment: despite “wood-pain” being the obvious name for all woodpeckers, only 12 species of woodpecker are in the “wood-pain” genus, out of a total of 240 species.

Side-side-side comment: There’s another genus called Xiphidiopicus which as far as I can tell translates roughly to “divine sword woodpecker” or something like that. Which is an entirely different, and totally badass, mood!

 

Back to the main point: if you’re like me-from-a-few-weeks-ago, you’ve probably heard that the reason that woodpeckers don’t get brain damage, even has they bang their heads seriously hard against seriously-hard wood, a serious number of times and seriously fast …

 Is that the woodpeckers have some sort of cushioning within their head. Like a football or bicycle helmet.

 Right?

 So it turns out that common sense, as well as some recent scientific investigation, tells us that this is wrong!

 Common Sense: “If the beak absorbed much of its own impact, the unfortunate bird would have to pound even harder.” (ok, not only is this common sense, it’s from an article in medical journal The Lancet, from 1976).

 Recent science: Sam Van Wassenbergh, Maja Mielke; Why woodpeckers don’t get concussions. Physics Today 1 January 2024; 77 (1): 54–55. https://doi.org/10.1063/PT.3.5385

 

They took high-speed video of woodpeckers doing their thing, and then basically ran the same calculations used on crash-test dummies to figure out how deadly a car crash would be on a human. This showed that the whole head of the woodpecker went through the same deceleration – there is no internal shock absorption!

 

Image: Tracking impact acceleration on the beak and near the braincase of a pileated woodpecker. (b) This representative example shows the deceleration of those landmarks. Source: https://doi.org/10.1063/PT.3.5385

 

Oookaaaaayyyyy, you say, so how is it that woodpeckers avoid concussions, when their brains are hitting 400g with all of that back-and-forth, and a piddly 135g of acceleration will give a human a concussion?

 Basically, it’s because they’re bird-brained. As in, woodpeckers have really small brains. And because of the much lower mass, their brains can withstand greater acceleration before the force becomes great enough to cause damage. (Remember F=ma from highschool physics?)

 Unfortunately, this physics-applied-to-brains means two things:

1. We are no closer to a miracle concussion-preventing helmet
2. Giant woodpeckers can’t exist