Science Questions

why don't woodpeckers get brain damage when they hammer into a tree? Neil

In the late 1970s scientists tackled this by using a very fast camera capable of taking 2000 pictures every second. Analysis of these images showed that a woodpecker's head tolerates a force of about 12 thousand times the force of gravity whenever it hits something, which is a considerable force going through its head, so why shouldn't it get brain damage? Well there are various woodpecker adaptations which means they are able to cope with this trauma, and one of them is that their skull bones are quite spongy which mean they can absorb shocks very well. Another adaptation is that a woodpecker's brain is small and so has a very big surface area to weight ratio, and so the force is spread over a large area. The photography also revealed that woodpeckers line their heads up very straight with whatever they tap into, so there's no rotational injury which, at least in people involved in car accidents, is a major cause of brain injury as delicate nerve fibres are torn by the brain trying to twist on itself.

October 2004