Today in Nature: Why don't woodpeckers get concussions?

August 29th: So, if boxers, hockey and football players get concussions, why don't woodpeckers? Turns out that their heads have evolved to soften the blow. Their rapid pecking at trees can generate impacts 1000 times the force of gravity, but their necks absorb much of the shock, while their skulls are thickened in front to protect their brains. If only helmets on hockey players were so effective....