LOL,...every animal knows how to fight. Apes are better fighters than humans barehand. Considering we're really not that far down the evolutionary chain, any assumption that codified systems of fighting were nation-specific with a single root and method of training---that's about the most ridiculous thing I've ever heard.
How do apes fight? They hit, they run, they wrestle, they ground and pound. Not MMA...LOL. Just fighting. All greater apes know how to do it. Some just do it a little better than others.