> "If we could get more of them doing it, it would be great," he joked. Karisoke's Vecellio, though, said actively instructing the apes would be against the center's ethos. "No we can't teach them," she said. "We try as much as we can to not interfere with the gorillas. We don't want to affect their natural behavior."

I would think that the main danger is in habituating the gorillas to humans, teaching them that we're safe when we're not. It may be better if any human interaction with them is aversive but not damaging, like pepper spray.