Its possible, though not likely that speciation can create a drastic change in diet. There are plenty of books out there that discuss the whys and hows better than I could recreate their discussions here. I found The Greatest Show on Earth a particularly clear description, but if you're offended by anti-religious speak you may not be able to get through it.
Also, we didn't "evolve" from apes. We are apes, right now.
You may find this interesting--
Clarifying the Human Species:
Humans didn't evolve from Apes, we are Apes. It’s common to think that we are something totally different or special, but we are just another Ape... But, what I think you’re trying to say is you don’t believe evolved from animals like: Chimps, Orangutans, or Guerrilla. We didn’t… but we share a common ancestor.
Ya I agree. We are all monkeys.................................. ARE YOU SERIOUS??
No, not monkeys. Apes. And yes, Humans are a type of ape.
Definitely ;) That's makes TOTAL sense!! xD
You sound sarcastic. Its just a plain fact.
Evolution was invented by a guy who hated the world and God and wanted an alternate route, and came up with a ridiculous theory that people who don't want to believe in God go for.
No one chooses to believe in evolution because they hate gad. No one chooses to believe in evolution at all for that matter. Facts also don't require belief to be true.
Heres one for those who like the alien-engineering theory.