What? Looking at other apes is a poor indicator. What an animal eats has to do with it's environment and it's digestion mechanisms. Some apes largely ate grasses. Nutrients matters, but largely is solved by eating a varied diet.
You might have noticed that we do something other species don't. Cooking! It's a pre-digestion mechanism that saves a lot of work. Combined with our omnivorous digestive system we can probably be considered radically distinct from our ape ancestors (in a good way).
The evidence seems rather sketchy, though. From the article:
"If early humans ate grass-eating insects or large grazing animals like zebras, wildebeest and buffalo, it also would appear they ate C4 grasses.
If they ate fish that ate algae, it would give a false appearance of grass-eating because of the way algae takes up carbonate from water, Cerling says.
If they ate small antelope and rhinos that browsed on C3 leaves, it would appear they ate C3 trees-shrubs."
Seems more likely that they ate the animals, though. I mean, otherwise, shouldn't our teeth have been different by now?
Sorry for not finding a name, but there's an early hominid (divergent from us, but not an ancestor) that ate C4 grasses and had the jaw shape for it. They are now extinct. Point being that we can't extrapolate from other species (apes) even if we share an ancestor.
Early humans were probably mostly scavengers anyway until fairly close to the agricultural period. Its unlikely they ate much meat.
You might have noticed that we do something other species don't. Cooking! It's a pre-digestion mechanism that saves a lot of work. Combined with our omnivorous digestive system we can probably be considered radically distinct from our ape ancestors (in a good way).