This is important also for our initially skeptical reaction to it. The fact that humans assumed that apes would never war shows the prevalence of the "noble savage" myth even among scientists.

The noble savage myth in turn is a modern (post-Renaissance) secularized version of "the fall" described in Genesis and other ancient religious myths. The idea is that God -- being good -- would never have intended nature to be full of violence and deception. In theology this is known as the problem of evil. Most Western religions solved the problem of evil by blaming ourselves -- we did it, and we inherited this sin, etc. Modern secular nature-worshippers (what I call "religious greens") have simply substituted nature for God and civilization or some other development for the fall-- it's a direct remapping of Judeo-Christian mythology.

"Uncorrupted" nature and pre-fall humans (if any exist, e.g. isolated tribes) must not have these characteristics according to the myth. If they are observed they must be a result of our "fallen" interference.

In reality nature is full of deception and warfare at all levels, and not just in predator-prey or parasite-host interactions but among members of the same species. This supports either an atheistic/naturalistic universe or a God whose nature is rather more complex than "God is good." If you want to keep theism, a polytheistic cosmology is also possible. Cultures who have a dualistic view of God or a polytheistic cosmos don't have monotheism's same sort of problem of evil.

This is also why I think suspension of value judgement is very important when studying nature, even human nature. Sometimes I gain the deepest insights into human behavior and culture when I try to look at things without making any value judgement.