If you’ve ever hopped on a bike or geared up for football practice, you know it’s critical to wear a helmet during any activity that puts your brain at risk.
But what if you were a woodpecker? For a long time, biologists thought these “jackhammers of the forest” had protection built in. Many helmet designs have been inspired by the spongy bone in woodpeckers’ skulls! But a new study suggests that it’s actually the relatively small size of their brains that protects them from concussions.
After watching high-speed footage of the birds pecking, researchers saw no evidence of shock absorption. The birds’ brains were traveling at full speed at impact. “They just don’t have the neck muscle power to reach the potentially dangerous speeds,” says Sam Van Wassenbergh, a professor of biomechanics at the University of Antwerp in Belgium. That’s because the more momentum (which measures the mass times the speed) of an impact, the more brain damage will occur. Because their brains are so small, woodpeckers would need to peck twice as fast—or find trees four times as hard—to be in any real danger.