Evolution and what have the apes ever done for us?
When it comes down to it I do believe that the evolving human/primate having dexterous fingers and a largely meat diet had a lot to do with our evolution.
The developing brain and those fingers and eventually the opposable thumb enabled early Man the hunter to put his thoughts to better use. I mean. There were and are PLENTY of animals that rely on their hunting skills and who have OODLES of thinking-time on their hands but who will never invent the flint tool or dig a pit and put sharpened sticks at the bottom with which to easier catch their prey, simply because they cannot grip.
I can just imagine a pride of lions or a pack of wolves thinking along similar lines in their down-time.
"Hey, Leo! Wouldn't it be great if we could make some sort of trap to catch Gnu instead of having to chase them for miles in the heat of the day?"
"F**k off back to sleep, you silly ass. How in Dog's name are we going to dig with these silly paws??"
"Maybe we could employ a few of those apes?"
"Hahahahahahahahaheeheehee!"
"See! Even that sodding Hyena thinks you're crazy!!"
"Just a thought."