I am dubious re the mushroom "experiment". I seriously doubt that one could avoid all poisonous foods just by taste.
There are conditions, of course. One must be careful and only mushrooms with an appetizing smell should be put in the mouth, a small piece first. It takes some seconds for the taste to be evaluated, say 10 – 12 s to be on the safe side. If a bad taste appears, then the stuff must be spat. The problem is that we have been taught ever since childhood to never spit food, to always swallow what is in the mouth; this tends to become an automatism, and a dangerous one from which we’ve got to get disaccustomed.
Other conditions are that the mushroom (like any other potential food) must be raw, un-spiced and un-mixed.
I don’t know of a single case of an “instincto” having been intoxicated by a wild stuff, mushrooms included. Obviously, animals avoid poisonous things, otherwise there wouldn’t be any wild fauna and we wouldn’t be here. The ones who poisoned themselves died and the ones who could best avoid poisoning had more chances to survive and have offspring. Those would have inherited the genes of their parents and thus could avoid toxic stuffs as well. Isn’t it logical?
Natural selection as given us the ability to instinctively select the most suitable foods and to avoid poisoning by things naturally present in the environment. As regards the other stuff, I already pointed out that not only are those foods high in antinutrients, but even if one reduces the levels of antinutrients a bit by soaking in water etc., these foods are still not meant to be eaten by humans so we are not adapted to them well.
Yes, you already pointed it out and I already replied that anti-nutrients are sometimes beneficial (Wikipedia dixit – you may want to correct Wikipedia if that’s wrong) and thus would be incorrectly labeled in some cases. Biochemistry and metabolism are so complex that our theoretical models can’t take account of all the variables: they are only very basic and often lead to wrong assumptions.
Wild grains are present in nature and some are palatable, so our ancestors would certainly have eaten those sometimes, especially since they were unlikely to know about anti-nutrients.
We can’t know by theoretical assumptions, our knowledge is ways too limited. The only way to know is by experimenting, on animals and on ourselves. That’s what GCB and friends have done, back in the 60’s and AFAIK
they were the firsts to discover the harmful effects of cultivated grains and dairy. Their experiments showed that wheat was the most harmful grain, others being also detrimental but when consumed in large amounts only. No noxious effects could be demonstrated with small amounts.
Dairy is another story: small amounts of the best raw milk, even from their own goat, triggered troubles.
Besides, you are using the same crooked, lame argument that cooked-foodists often use against rawpalaeos, namely that as long as one only cooks a food a little bit, it does not really matter.
That’s different. We know for sure that heating organic molecules produces an incredible array of new compounds, some of them undoubtedly toxic. Meticulous and long experiments also showed that slightly overheated food (55 – 60° C) was troublesome, often even more than thoroughly cooked food.
Cheers
François