Yeah I was thinking the same thing. What about the ice age that wasnt exactly one year long.
I am a welder not an anthropologist but in my imagination early humans and other hominids were opportunists and no doubt before cooking most vegetables may have seemed or may have actually been inedible without proper preparation. .
I am from the side of the debate that most early humans were carnivores. Once they mastered the spear there was not much more reason to forage for leaves or bugs.
But for sure we have evolved past that. I have heard people say that you can live on meat alone, "it has everything your body needs" Im sure you could live on meat alone.Im just not sure how long.
One of the most interesting things about early hominid history is the symbiotic relationship between our diet and our brains. I read once that our brains were able to develop by leaps and bounds due to the high fat content of the diet that our early ancestors enjoyed, and the bigger our brains got, the better we became at finding the fat.
Of course, it was our omnivorous ability and blatent opportunism that got us through the rough patches, but in general it was having the right teeth and the right brains in the right place at the right time that eventually landed a couple of naked pink monkeys on the moon.
As for how long you can survive on meat, the anthropologic answer is "long enough." Which is to say that if I were a member of a primitive tribe, I'd have one foot in the grave right now - if I was very lucky.