Good point but how can it be evil if they think it is good for them to survive. They would then think they are doing good for just themselves. But now as we have deeper thought we can analyze many things and separate good from bad so maybe ever since 5,000 b.c.e. people began deeper thought of organization and the separation between good and bad.
If there is a society of jut single people who survive with no rules no guidelines then maybe in our eyes they are commiting evil but in theres it is good because they dont know any better. just a thought