Helpless Impulses
Another common side effect of near fainting while conscious is both disgusting and tactically brilliant. A vagal state can make an animal lose control of its bodily functions. Some animals urinate or defecate under extreme emotion or fear. Many predators find urine or feces repugnant and will leave. Dogs are known to retreat at the smell of skunk; frightened shrews produce such foul odors from their anal pockets that even ravenous badgers keep their distance. Vomiting by the would-be prey can have the same conveniently repellant effect on the predator.
This potentially embarrassing loss of bodily control in response to fear is one vestige we humans probably wish we’d evolved out of. But in fact it may occasionally serve a protective function for us as well. Rape-prevention educators sometimes instruct women to urinate or vomit if rape is imminent. In some cases, the attacker will be repulsed and withdraw. A more common phenomenon is seen in women who successfully avoid sexual assault by fainting or by entering a “near fainting while conscious” state. Psychologists have studied cases of this and compared them to immobility reactions in animals. They suggest that when fighting back isn’t an option, not struggling may defuse the situation and reduce the likelihood of rape.† While far from foolproof, fainting succeeds enough of the time to warrant a serious consideration of its evolutionary roots.
