I think the predators evolved along side the aliens (aliens never changed) (because the preds can see an ora around them naturally), but the aliens were not there naturally maybe a jockey ship crashed on their planet like 100000000000 years ago.
The predators were such good hunters because they had to find food and the aliens had wiped most of it out before the first predator records. There were very few predators left to hunt so no members of the nomad clans (the predator could never stay I one spot because aliens would know their there) were expendable so they had to be heavily trained.
In a strange turn of events the predator species went through some incredible changes. In about 150years the predators learned and refined long distance space travel and how to harnus plasma (and much more). Which may show some kind of alien (not xeno) influence. The changes were so quick that did not have time to fully adapt their culture to the changes (keeping their tribal ways).
I just made this up and I wanted to share.
game over man, game over... o 2 more lives. im an R.P.G alien ( new pic same great tast ) - my avatar looks like a evil retard no moresuper nerds alone to gether, super nerds, nerds for ever