True to their name, woodpeckers hammer away at wood with their beaks. And when they do, they can experience forces of 1,200 to 1,400 g’s (g-force = the force of acceleration). In contrast, a force of 60-100 g’s can give a human a concussion. The astonishing fact that a woodpecker can undergo fourteen times that without getting hurt has led helmet makers to model their designs on these birds’ skulls.
But a new study using some of our bird specimens—more specifically, their brains—complicates this story.
“There have been all kinds of safety and technological advances in sports equipment based on the anatomic adaptations and biophysics of the woodpecker assuming they don’t get brain injury from pecking. The weird thing is, nobody’s ever looked at a woodpecker brain to see if there is any damage,” says Peter Cummings of the Boston University School of Medicine, one of the new study’s authors.
Since excessive tau protein in humans can be a sign of brain damage, researchers decided to check woodpecker brains for build-up of the same protein. We loaned some of our bird specimens pickled in alcohol—Downy Woodpeckers to check for tau, and Red-winged Blackbirds that likely wouldn’t have brain injuries, as a control. Researchers took incredibly thin slices of both birds’ brains—less than a fifth the thickness of a sheet of paper—then stained them with silver ions to highlight any tau proteins.
The verdict? Woodpeckers’ brains had far more tau protein accumulation than the blackbirds’ brains. But, while excessive tau buildup can be a sign of brain damage in humans, the researchers note that this might not be the case for woodpeckers—one possibility is that the tau protein is protective rather than a sign of damage in these birds. (If woodpeckers have been around for 25 million years, why wouldn’t they have evolved to avoid brain injury caused by pecking?)
So, woodpeckers show signs of what looks like brain damage in humans, but it might not be a bad thing. Either way, the researchers believe that the study’s results could help us humans—even helping to make football equipment safer for kids.
This study was published in PLOS ONE.