Not sure if that is a list of causes in descending order, but I'd't sure as he11 hope not.
We were driving through Central America about 50 years ago and saw a big police presence up on a hillside with a big crowd. We asked someone what it was, they said it was a machete fight, probably over land, women or cattle.
Well, I would think that usually when people are fighting over land they are actually fighting over the resources of that land that will enable their families, their tribe/group/nation to thrive and produce young.