Pets do a lot of weird things, and most of them have perfectly boring explanations. The head shake is one of the more entertaining ones, and the science behind it is actually pretty interesting—so here it is. Why cats do it Cats shake their heads when the nerve endings on their heads get stimulated, according to Sarah Crowley, an anthrozoologist at the University of Exeter. “The physiological driver for it is stimulation of the very sensitive hairs and nerve endings around the top of the head, particularly around the ears,” she told Live Science . Videos by VICE Turns out your cat’s nervous system is doing exactly what it’s supposed to. Crowley says the reflex comes from the highly sensitive hairs and nerve endings around the top of the head, especially near the ears—so when you nail that scratch, the cat’s body responds whether it wants to or not.…