Here are 4-5 paragraphs of the book "Food of the Gods" written by Terence McKenna. Terence McKenna is a very credible ethnobotanist, philosopher, psychonaut, researcher, teacher, lecturer and writer on many subjects, such as human consciousness, language, psychedelic substances, the evolution of civilizations, the origin and end of the universe, and alchemy. This book is about how hallucinogens greatly helped hominids become much more intelligent and very possibly gave us language. I highly recommend getting the book it is very good and here is a example.
SpoilerMy contention is that mutation-causing, psychoactive chemical compounds in the early human diet directly influenced the rapid reorganization of the brain's information-processing capacities. Alkaloids in plants, specifically the hallucinogenic compounds such as psilocybin, dimethyltryptamine (DMT), and harmaline, could be the chemical factors in the protohuman diet catalyzed the emergence of human self-reflection. The action of hallucinogens present in many common plants enhanced our information processing activity, or environmental sensitivity, and thus contributed to the sudden expansion of the human brain size. At a later stage in this same process, hallucinogens acted as catalysts in the development of imagination, fueling the creation of internal straragems and hopes that may well have synergized the emergence of language and religion.
In research done in the late 1960's Roland Fischer gave small amounts of psilocybin to graduate students and then measured their ability to detect the moment when previously parallel lines became skewed. He found that performance ability on this particular task was actually improved after small doses of psilocybin.
When I discussed these findings with Fischer, he smiled after explaining his conclusions, then summed up, "You see what is conclusively proven here is that under certain circumstances one is actually better informed concerning the real world if one has taken a drug than if one has not." His facetious remark stuck with me, first as an academic anecdote, later as an effort on his part to communicate something profound. What would be the consequences for evolutionary theory of admitting that some chemical habits confer adaptive advantage and thereby become deeply scipted in the behavior and even genome of some individuals?
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Some people will think this is crazy lol.So how did the mushroom modifications get into the genome?
The short answer to this objection, one that requires no defense of Lamarck's ideas, is that the presence of psilocybin in the hominid diet changed the parameters of the process of natural selection by changing the parameters of the process of natural selection by changing the behavioral patterns upon which that selection was operating. Experimentation with many types of foods was causing a general increase in the numbers of random motivations being offered up to the process of natural selection, while the augmentation of visual acuity, language use, and ritual activity through the use of psilocybin represented new behaviors. One of these new behaviors, language use, previously only a marginally important trait, was suddenly very useful in the context of new hunting and gathering lifestyles. Hence psilocybin inclusion in the diet shifted the parameters of human behavior in favor of patterns of activity that promoted increased language, acquisition of language led to more vocabulary and an expanded memory capacity. The psilocybin-using individuals evolved epigenetic rules or cultural forms that enabled them to survive and reproduce better than other individuals. Eventually the more successful epigenetically based styles of behavior spread through the population along with the genes that reinforce them. In this fashion the population would evolve genetically and culturally.