[twobitshifter]

Yes if you eat grass and somehow survive to procreate you will have adapted to be able to digest it and sustain your species. Of course if you lack the genes you’ll die off and if the whole species lacks any genes and all that’s left to eat is grass, we all die. I believe from studying skeletons we know that agriculture first led to a decline in physical fitness and overall health - evidence that we weren’t well adapted at that time.