A chimpanzee did pre-planned violence, something we believed only human beings had the intelligence for. While that’s interesting & –of course–comical behaviour, it might conceivably have been a safety hazard for visitors. So we castrated him. This solution (a) maintains the very important distinction between humans & other primates; & (b) eliminates the risk of him passing on his genetic material. What is the very important distinction between human beings & other primates, I hear you ask ? It’s that human beings can fly to Sharm el Sheikh for £29, you loser.