Before he turned thirty, a young Harvard botanist had already carried two of the world’s most powerful plants of the gods, psilocybin mushrooms and ayahuasca, from Indigenous hands into Western science. That botanist was Richard Evans Schultes, and his journey is retraced here by ethnobotanist Dr. Mark Plotkin, PhD, president of the Amazon Conservation Team, with Brian Hettler, Pascual Gonzalez and their colleagues. This article follows Schultes from the Mazatec highlands of Oaxaca to the Sibundoy Valley of Colombia, and traces how those encounters shaped the psychedelic landscape we know today.

Mexico and the Magic Mushrooms

The story begins with a mistake. The American ethnobotanist William Safford had argued that the Spanish chroniclers who described intoxicating divinatory mushrooms among the Aztecs were simply wrong: the Aztecs, he said, had misled the Catholic clergy to protect their true sacrament, peyote. While researching peyote for his undergraduate thesis at Harvard, Schultes had reason to doubt this. Peyote was a cactus confined to a narrow strip along the Texas–Mexico border, and even a layperson could tell a dried mushroom from a dried cactus. The Spanish accounts, he found, were strikingly accurate about Aztec life, describing how psychotropic mushrooms were served at imperial coronation banquets under the name teonanacatl, the “flesh of the gods.”

The breakthrough came by chance. While studying peyote specimens in the herbarium, Schultes stumbled across a letter from the physician Blas Pablo Reko, who insisted Safford was mistaken: the sacred fungus, he wrote, was still used under its old name by Indigenous peoples of the Sierra Juarez in Oaxaca. Schultes resolved to document the Mazatec peoples for his doctoral research, and in July 1938 he travelled by train, mule, and on foot to Huautla de Jiménez, the Mazatec capital. There, local informants confirmed that the Psilocybe mushrooms they called los niños santos, “the little sacred ones,” were central to both their religious and healing practices.

The Hidden Chain: From Mazatecs to Hofmann

Popular accounts usually credit the banker R. Gordon Wasson with bringing the magic mushrooms of Mexico to Western attention. But the real chain of transmission ran through people whose roles have largely been forgotten. Chief among them was Valentina “Tina” Wasson, Gordon’s wife, a Russian-born physician whose curiosity about wild mushrooms first drew the couple into a lifelong study of fungi in human history. It was Tina who, in 1949, wrote to the poet and classicist Robert Graves for help with a centuries-old puzzle about the death of the Roman emperor Claudius.

That correspondence proved pivotal. In 1952 Graves sent the Wassons a pamphlet article that cited Schultes’ 1939 and 1940 papers as the primary sources on Mexican ethnomycology. Inspired, the Wassons contacted Schultes himself for guidance and set out for Huautla. In 1955 the Mazatec shaman María Sabina invited them to a velada, a mushroom ceremony; Gordon’s 1957 Life article, “Seeking the Magic Mushroom,” became an international sensation. The mushrooms travelled on from there to the French mycologist Roger Heim and finally to the Swiss chemist Albert Hofmann, who in 1958 isolated and named the active compounds psilocybin and psilocin.

Psilocybin’s Unexpected Medical Legacy

Psilocybin is now sweeping the world: mycologist Paul Stamets has called it the “Einstein Molecule,” and the practice of microdosing has spread on claims of relief from depression, anxiety, and insomnia. Yet one consequence of the mushroom research is almost entirely unknown outside the field. In one of his final papers, “Medicinal Chemistry’s Debt to Ethnobotany,” Albert Hofmann described how he and his colleagues used the molecular nucleus of psilocybin to develop an entirely new class of cardiac drugs.

The first of these was marketed as Visken, an early member of the class now known as beta blockers, which have improved and in many cases saved the lives of tens of millions of people. In Hofmann’s own assessment, without the investigations into the hallucinogenic Mexican mushrooms, Visken and the other beta blockers would not have been developed. A sacred fungus from a remote Oaxacan mountain town, in other words, helped seed one of the cornerstones of modern cardiology.

Ayahuasca and the Northwest Amazon

The second great thread of Schultes’ work is ayahuasca: the Amazonian liana and the brew prepared from it, today consumed from Israel to Indonesia. The Kechua name means “vine of the soul,” reflecting the belief that the drink frees the soul from the body to wander, commune with ancestors, and return at will. Schultes himself wrote that ayahuasca was so deeply rooted in native mythology and philosophy that its great antiquity as part of aboriginal life could not be doubted.

Pinning down where the vine and the ceremony originated has proven difficult. The earliest written accounts, by Jesuit missionaries, naturalists, and explorers from the 1730s onward, cluster in the western Amazon, along rivers in what are now Ecuador, Peru, Colombia, and Brazil. Cumulatively they point to the northwest Amazon as a likely center of origin. Yet the picture is more complex: chemical analysis of mummy bundles has revealed ayahuasca alkaloids in a Tiwanaku grave in Bolivia dated to around 1000 AD, showing the brew was also used ceremonially in the Andean highlands in pre-Columbian times.

Sibundoy: A Crossroads of Healing Plants

The detailed scientific study of ayahuasca began when Schultes reached the Sibundoy Valley of Colombia in December 1941, funded by a grant to study Amazonian arrow poisons. Sibundoy is a bowl-shaped depression on the eastern edge of the Colombian Andes, ringed by four volcanoes and frequently shrouded in cloud. Because it sits near the narrowest, lowest pass of the northern Andes, it has been a crossroads since the first humans arrived, a place where itinerant healers traded medicinal plants from both highland and Amazonian regions. So many healing species were propagated there that Schultes concluded Sibundoy held more hallucinogenic plants than anywhere else on earth.

Two Indigenous peoples live in the valley: the Kamsá, whose language is unrelated to any other and who claim to have been the first people to enter Amazonia, and the Inga, whose tongue is related to Quechua. For both, the most essential healing plant is ayahuasca, el remedio, “the medicine.” Schultes’ mentor there was Salvador Chindoy, a renowned Kamsá taita, or paramount shaman, who said his knowledge came from the plants themselves, speaking to him in dreams and visions. Schultes’ work was greatly aided by Chindoy’s nephew Pedro Juajibioy, who became a skilled botanist and revered healer and later guided ethnobotanists such as Wade Davis and Timothy Plowman.

The Lessons and Legacy of Schultes

To his last days, Schultes predicted that other mind-altering substances awaited scientific discovery, and he was right. Since he helped organize the original ESPD Symposium in 1967, compounds such as iboga and kratom have come to light, and researchers have learned that understudied creatures like frogs and ecosystems like coral reefs can yield novel medicines. Substances Schultes helped bring forward are now being explored for conditions his Indigenous teachers never named, from PTSD to asthma.

Three lessons run through his life and remain valid today: that nature is an almost inexhaustible source of therapeutic compounds; that Indigenous peoples are both the finest teachers about these ecosystems and their best stewards; and that protecting this biocultural legacy serves everyone’s interest. The world has awakened somewhat to these truths during the so-called Psychedelic Renaissance. Yet the destruction of primary forests and Indigenous cultures continues apace, and the challenge of safeguarding this legacy, the libraries that vanish each time a healer dies, remains as urgent as ever.

Frequently Asked Questions

What is psilocybin?

Psilocybin is the psychoactive compound found in certain mushrooms of the genus Psilocybe, long used by the Mazatec and neighbouring peoples of Oaxaca, Mexico, who called the mushrooms los niños santos, “the little sacred ones.” The Aztecs knew them as teonanacatl, the “flesh of the gods.” The compound was first isolated and named by the Swiss chemist Albert Hofmann in 1958, after botanical samples reached him via the mycologist Roger Heim. Today psilocybin is widely researched for its therapeutic potential in conditions such as depression and addiction.

What does ayahuasca mean and where does it come from?

Ayahuasca comes from the Kechua term meaning “vine of the soul,” a name reflecting the belief that the brew frees the soul from the body to wander and commune with ancestors before returning. It is made from an Amazonian liana, usually Banisteriopsis caapi, combined with admixture plants. The earliest written accounts cluster in the western Amazon, suggesting a northwest Amazonian center of origin, though chemical analysis of Andean mummies shows it was also used ceremonially in the highlands by around 1000 AD.

Who was Richard Evans Schultes?

Richard Evans Schultes is widely regarded as the dominant figure in twentieth-century ethnobotany. Learning from his Indigenous teachers and guides, he helped bring peyote, psilocybin, and ayahuasca to wider scientific attention, much of it before he turned thirty. Beyond hallucinogens, he carried out important research on coca, cannabis, Hevea rubber, and orchids. He was also one of the organizers of the original 1967 ESPD Symposium in San Francisco, and his fieldwork in Mexico and the Colombian Amazon laid foundations the field still builds on.

How did Schultes document the magic mushrooms of Mexico?

Schultes suspected that earlier scholars who dismissed Aztec mushroom use were wrong. A chance discovery of a letter from physician Blas Pablo Reko, insisting the sacred fungus was still used in Oaxaca, prompted him to make it his doctoral subject. In July 1938 he travelled to Huautla de Jiménez, capital of the Mazatec peoples, where local informants confirmed the Psilocybe mushrooms were objects of veneration. He published two landmark papers on the subject in 1939 and 1940, whose importance took decades to be appreciated.

How is ayahuasca used by the peoples of the Sibundoy Valley?

In the Sibundoy Valley of Colombia, the Kamsá and Inga peoples regard ayahuasca as their most essential healing plant, calling it el remedio, “the medicine.” It is central to the practice of the taitas, the paramount shamans of the region. Schultes’ mentor there, the Kamsá taita Salvador Chindoy, described ayahuasca as the ultimate medicine and the ultimate plant teacher, and said his knowledge had been learned from the plants themselves, who spoke to him in dreams and visions.

Does psilocybin have real medical value?

Beyond its much-discussed potential for depression, anxiety, and addiction, psilocybin has already left a concrete medical legacy. Albert Hofmann described how he and his colleagues used the molecular nucleus of psilocybin to develop a new class of cardiac drugs, the first marketed as Visken. These became the beta blockers, medicines that have improved and saved the lives of tens of millions. Hofmann stated plainly that without the investigations into the Mexican mushrooms, beta blockers would not have been developed: a striking example of traditional Indigenous knowledge feeding mainstream medicine.

How old is the use of ayahuasca?

The exact antiquity of ayahuasca is impossible to determine, but the evidence points to great age. Schultes argued that its deep roots in native mythology and philosophy left no doubt about its antiquity. Hard evidence has since accumulated: chemical analysis of a roughly 1,000-year-old ritual bundle from the Tiwanaku culture in Bolivia revealed ayahuasca alkaloids, and a later Inca-period grave in Peru showed similar results. Together these findings confirm the brew was consumed ceremonially across both Amazonian and Andean cultures well before European contact.

Where can I learn about ethnobotany properly?

The McKenna Academy Living Library offers courses that teach ethnobotany the way Schultes practised it, with the culture kept firmly attached to the plant. Its ethnobotany pathway covers the relationship between people and plants in the twenty-first century, the shamanic art of healing, the chemistry of psychoactive plants, and the traditions of Amazonian and Andean medicine. Taught by recognised authorities, the courses honour Indigenous knowledge as living wisdom held by named communities, not as a historical curiosity. That is exactly the spirit of Schultes’ lifelong work.

Dr. Mark Plotkin, PhD

Ethnobotanist · President, The Amazon Conservation Team

Mark Plotkin, PhD, is an ethnobotanist who serves as president of the Amazon Conservation Team, an organization that has partnered with more than 90 Indigenous groups to map and improve the management of almost 100 million acres of ancestral rainforest. He is the host of the popular podcast “Plants of the Gods: Hallucinogens, Healing, Conservation and Culture,” and was a student of R. E. Schultes. This paper was written with co-authors Brian Hettler, Pascual Gonzalez, and colleagues at The Amazon Conservation Team.