> Perhaps a particular chimp or gorilla was having a really bad day and just went out looking for a fight. This doesn't necessarily contradict the food compet

> Perhaps a particular chimp or gorilla was having a really bad day and just went out looking for a fight. This doesn't necessarily contradict the food competition or climate change hypothesis. To the individual ape it might seem that he's just having a bad day, but then you could look at weather/food data and compare it to incidence of violence and see a causal relation. It would actually be surprising if those things didn't affect ape behavior.