"Wild chimps “recruited” by poachers for entertainment watch as their mothers are gunned down — the only way a chimp mother would ever relinquish a child. Chimps born in captivity are spared that experience, but they suffer the same premature separation from their mothers, isolation from their normal social groups and often mistreatment from trainers and keepers, all traumatic events that have been shown to cause deep psychological scarring and, as in human beings, can lead an animal to overreact to the slightest stimuli: the look in someone’s eye, the color of someone’s hair or, as with Ms. Herold’s friend that day, hair done up in an unaccustomed style. These are, in short, deeply conflicted beings, evolutionary anomalies that only we could have created: chimps with names and yet no recollection of trees."