Sure, just don't forget that psilocybin gave us language.
Traditionally, when scientists spared a thought for our hunting and gathering forebears, they focused on the hunters and the meat they brought in. But it may be that it was our ancestors' less glamorous ability to gather, eat and digest roots, bulbs and tubers -- the wild versions of what became carrots, onions and potatoes -- that increased the size of our brains and made the hunt and the territorial expansion that came with it possible.
In a paper published in September in Nature Genetics, George Perry, a graduate student at Arizona State University, Nathaniel Dominy, an anthropology professor at the University of California, Santa Cruz, and their colleagues demonstrate something significant: unlike our fellow primates, modern humans have many copies of a gene that makes a protein in our saliva that is crucial for breaking down starch into glucose. Our brains run on glucose. DNA and saliva samples taken from populations all over the world -- from locals in Arizona and Japan to the Hadza, hunter-gatherers in Tanzania, and the Yakut, Siberian animal herders and fishermen -- showed that if you have more copies of the gene amylase 1, you have more of the protein. Groups like the Japanese, who eat diets high in starches, have on average a higher number of copies of the gene. "In human evolution, starch may have played a particularly important role," Perry says. After all, if you possessed the ability to efficiently convert starch into the glucose that fuels your brain, "you'd have a big advantage nutritionally," Dominy says. [From Starch Made Us Human]
