headyfunkup said:

from the book Food Of The Gods by Terrence Mckenna

A NEW VIEW OF HUMAN EVOLUTION
The first encounters between hominids and psilocybin-containing mushrooms may have predated the domestication of cattle in Africa by a million years or more. And during this million-year period, the mushrooms were not only gathered and eaten but probably also achieved the status of a cult. But domestication of wild cattle, a great step in human cultural evolution, by bringing humans into greater proximity to cattle, also entailed increased contact with the mushrooms, because these mushrooms grow only in the dung of cattle. As a result, the human-mushroom interspecies codependency was enhanced and deepened. It was at this time that religious ritual, calendar making, and natural magic came into their own.
Shortly after humans encountered the visionary fungi of the African grasslands, and like the leafcutter ants, we too became the dominant species of our area, and we too learned ways of "keeping the bulk of our populations safe in subterranean retreats." In our case these retreats were walled cities.
In pondering the course of human evolution, some thoughtful observers have questioned the scenario that physical anthropologists present us. Evolution in higher animals takes a long time to occur, operating in time spans of rarely less than a million years and more often in tens of millions of years. But the emergence of modern humans from the higher primates-with the enormous changes effected in brain size and behavior-transpired in fewer than three million years. Physically, in the last 100,000 years, we have apparently changed very little. But the amazing proliferation of cultures, social institutions, and linguistic systems has come so
quickly that modern evolutionary biologists can scarcely account for it. Most do not even attempt an explanation.

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So, this theory tries to account for human evolution by hypothesizing that psilocybin-human coevolution and codependency created, or paved the way for, our multifarious conceptions of modern humanity?



Sure, psychoactive mushrooms might have played some sort of role in our evolution, but Terrence McKenna is going a bit too far with this particular theory. It's neither empirical, nor logical.