Be wary of chimps older than eight; that’s when they start to become volatile. A full-grown chimp, standing 3 to 5 feet tall and weighing up to 250 pounds, has five to ten times the strength of a same-size human being.
Male chimps seek to establish dominance over their family during adolescence, making them especially dangerous between ages 8 and 17.
Step 2: Don't underestimate them
Don’t underestimate their intelligence. The two male chimps that attacked a couple in 2005 got out of their cage by picking the lock.
Step 3: Don't show fear
If you think you’re in danger of being attacked, don’t show fear. Chimps don’t pick fights they don’t think they can win. If a chimp believes you have dominance, they’re less likely to attack.
Step 4: Protect your face
If a chimp makes a move toward you, protect your face: It’s the first thing they’ll go after. They also target fingers, hands, feet, testicles, noses, and ears. If you’re attacked, try to curl up into a ball to make those areas difficult to reach.
Step 5: Wear gear
If you’re going to be around an adult chimp, don the protective gear that animal handlers wear – face masks, goggles, rubber gloves, and boots.

Slight miscalculation.
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