If it’s literally true that anger is “necessary” for human survival then how do you explain people who don’t exhibit anger and yet flourish — life seems to offer us many examples. I asked my daughter if she’d ever seen me get angry and she said only once. But I think I get on pretty well on life, indeed, much better than if I was prone to anger. So how can it be necessary? It hasn’t proven to be in my life. And like I said in the article, anger often actually makes people weaker and less effective at fighting — see the George Foreman example where he got knocked on his ass by Ali due to his anger.