A Lifetime of Hammering Trees Might Affect Woodpecker Brains After All

A new study into the woodpecker brain shows proteins linked to CTE in football players, but it鈥檚 unclear whether birds suffer the same fate

Each time听a woodpecker听drums on a tree听to find food, build a nest, or attract a mate, it听gets hit with听up to 1,400 g鈥檚 of force鈥14 times the amount that would听trigger a concussion in humans. Thankfully, the bird听has a few ways to dampen the听blow: built-in shock absorbers, an enlarged brain case, and a specialized beak and skull that redirect pressure away from its head. As if that wasn't听enough, it can听also wrap its tongue听around the back of its head听to serve听as a cushion (when the organ isn't being deployed to trap dinner, of course).

These handy traits for concussion-heavy sports such as football and bike racing. The idea is simple: By modeling helmets and collars after a听bird that's built to headbang, outfitters can decrease the risk of chronic traumatic encephalopathy (CTE),听which is听听in NFL players, as well as听other brain diseases.

Or so the theory goes. While woodpeckers seem to fare okay in the long run, it's not known if their brains suffer from underlying damage.

鈥淭hey鈥檝e designed so much protective equipment based on the biomechanics of a woodpecker, but no one has ever looked at a woodpecker brain,鈥 says Peter Cummings, a neuropathologist at the Boston University School of Medicine. 鈥淭hat just blew my mind.鈥

And so Cummings, a football dad himself, set out to change that. He听and his听colleagues George Farah and Donald Siwek听secured 10听long-deceased woodpeckers (of different species) and five Red-winged Blackbirds听from two museum collections.听They then took up听scalpels and removed thin slices of the specimens听brains to test for deposits听of an abnormal form of听鈥渢补耻,鈥澛烬 specific protein linked to neurodegenerative conditions such as听CTE and Alzheimers.

The results, published听in the journal听last week, surprised them. 鈥淚 was thinking that there鈥檚 no way these woodpeckers would develop neurotrauma,鈥 Cummings says.听But his analysis revealed damaged,听鈥減hosphorylated鈥澨clumps of the protein听in the woodpeckers听brains. Blackbird brains, on the other hand, had no such deposits.

Tau, like most parts of the nervous system, is complicated. It听can protect听the passage of information between neurons, Farah says. But following repeated head trauma in humans, these proteins dislodge and accumulate in clumps that can slow the flow of information in the brain, resulting in cognitive and motor impairment. And that鈥檚 why finding similar buildups in the brains of woodpeckers鈥攁nimals adapted to headbanging鈥攚as so unexpected.

These are birds, not humans, so听you can鈥檛 conclude听that tau buildup听is indicative of听injury, let alone CTE.听

But that doesn't necessarily mean that听woodpeckers have brain damage. For starters, these are birds, not humans, so听you cant conclude听that tau buildup听is indicative of听injury, let alone CTE.听

And then there鈥檚 evolution. Woodpeckers have been drilling into trees for 25 million years; if that was causing symptoms like memory loss鈥攚hich presumably would reduce the birds鈥 fitness鈥攖hey听would have shifted their behavior long ago.听鈥淲hy would they still be pecking on trees if they are giving themselves neurodegenerative diseases?鈥 Cummings says.

It鈥檚 also possible that the buildups听serve听an important function in听woodpeckers鈥 brains.听鈥淚f you鈥檙e going to be jabbing your head into something at 1,200 g鈥檚, you鈥檇 want the neurons to be able to jostle,鈥 Cummings听says. 鈥淐ould it be that this [build up of tau] has a neuroprotective effect?鈥

Without further research, Cummingss听guess is as good as yours (okay, maybe a听little better).听But just听as theres a lot left to be learned about听bird brains, theres much to be done to understand how exactly CTE works. Woodpeckers, Cummings says, could help shed more light on both fronts.听