In the mid-80’s, a military helicopter touched down in the Peruvian Amazon, in a tribal Jívaro village. 40 men— on edge due to recent forced conscription into the Peruvian national army— came out to defend their village from more western incursion, with blowguns pointed at the sky, their darts laced with a paralytic poison.

In that helicopter were two researchers from Washington University, Memory Elvin-Lewis and her husband Walter Lewis. The two knew these men, so Walter waved his hand from their helicopter and the blowguns went down. After they landed and greeted the tribe, their work began. They would spend weeks among the Jívaro, who brought them medicines— made from the plants of the Amazon— that often proved as effective as western medicine. Even the poison on their darts, an alkaloid plant extract called curare, is now used as a muscle relaxant.

Courtesy of Memory Elvin-Lewis

Dr. Memory Elvin-Lewis and her husband, Dr Walter Lewis. “I couldn’t have done any of this without my life partner,” Elvin-Lewis said.

Many years later, having dedicated her life to the study of medicinal plants both in the Amazon and across the world, Memory Elvin-Lewis looks back on her time there with fondness. “It was a wonderful adventure, just a totally excellent and super adventure, and I miss it every day.” She recalled the beauty of these people’s spirituality, their connection with nature saying, “To me the most beautiful thing is that these people had three souls…the last soul is the most beautiful, the last place your soul resided is in a Blue Morpho butterfly.”

Rooted in St. Louis is a series about why you should care about plants; about why us living in urban jungles should care about the forests we left behind––perhaps the best way to do this is to learn from those who never left. For the Jívaro, plants are your food, your medicine, everything that keeps you alive.

Professor Emerita of Biology Memory Elvin-Lewis, with her collaborator and late husband Walter, studied these botanical cures, categorizing and cataloguing thousands of specimens in their seminal book, “Medical Botany: Plants Affecting Human Health.” Their “ethnobotanical” studies of traditional medicines have proved their continued relevance in the modern world.

Professor Elvin-Lewis began her career of ethnobotanical interest with dentistry, initially traveling to Peru to study the indigenous dental practice of teeth blackening––part of her National Geographic grant to study methods of dental hygiene around the world. “This was what we call a backburner project, a ‘Let’s have fun and see what happens’ thing,” she said. At that point, she was working in virology, and incidentally had identified what turned out later to be an early case of HIV. Experiments in microbiology sparked her further interest in medical botany. “I used those plants and found out how very bioreactive they were.”

And so she began to study traditional dental practices, teeth blackening among them. This practice exists both in East Asia and Latin America, and it is exactly what it sounds like. The practice is often culturally motivated, yet also correlates with improved dental health by preventing tooth decay.

In 1989, National Geographic documented one of the Lewises’ expeditions among the Jívaro people of the Peruvian Amazon in “Secrets of the Rainforest.” These tribes had a plethora of cures; they used more than 500 distinct medicinal plants, many of which proved effective in laboratory settings. The Peruvian Amazon had long before been proven to be pharmaceutically rich––the elemental anti-malarial drug quinine, familiar to many from the hydroxychloroquine controversy, originates in Cinchona tree bark. Yet quinine is a newcomer, a treatment for an old-world disease found by Europeans––the Lewises were interested in cures that had been preserved orally in native societies for generations. Many Jívaro women have their own herbal gardens, equivalent to a local drugstore, each plant with a purpose passed down with it.

Among a tribe, ideas about a plant’s proper use varied; Professor Elvin-Lewis recalled how, while the men of the tribe came forward to explain use of certain plants, the women would hang behind and laugh at their ignorance, confiding in her their real uses. Among the Jívaro, the women are the keepers of their own botanical knowledge. Take Balansia cyperi, a parasitic sedge fungus used to stimulate contractions during childbirth. Once brought back it was determined to be the only close relative of Claviceps, commonly known as ergot. Claviceps was used by European midwives in the same way as the Jívaro––these two societies, separated by the Atlantic, independently discovered the same fungal medicine.

The efficacy of orally transmitted medical knowledge is oft hard to conceive of, yet through years of trial and error the Jívaro discovered a myriad of medically useful plants, many of which were previously unknown to researchers before they were documented by the Lewises. Many of them are now found in “Medical Botany,” however one specimen that you will not find is the tropical tree discovered to be efficacious in treating Hepatitis B. “It is their knowledge to keep,” Elvin-Lewis told me.

After working on this topic for many years, Elvin-Lewis became quite aware of protecting the “intellectual property rights” of the people she studied––indeed she has yet to disclose the identity of this plant in any publication. The plant was discovered over a five-year study across four river systems in communities with hepatitis outbreaks. Eventually, when visiting a sick girl, she heard that “if you take this plant [the root of a tropical palm], you don’t die.”

The medicinal power of plants is global, but attitudes towards it are not universal. Women were the keepers of Jívaro medicine, male “witch-doctors” held such knowledge in West Africa— Professor Elvin-Lewis recalled the difficulty in getting these men to reveal their medicines. Ayurvedic medicine in India and traditional Chinese medicine constitute the most trusted medical knowledge for millions of people.

According to “Medical Botany,” 80% of the world’s population primarily use traditional medicine. Though they vary somewhat, they often come to the same conclusions. Both in China and India, the oil of Azadirachta indica (the neem tree) has been used both medicinally and as pesticide for 4,000 years. Families’ and cultures’ own idiosyncratic cures and systems do not act alone, but rather in conversation with each other––even among the upper Amazonian tribes, different groups were always in communication about their plants.

Starting in the ‘90s in Peru, Memory Elvin-Lewis witnessed the “sad disappearance of medical knowledge in accultured villages.” As contact with the west deepened, tribal peoples developed more western ways and started to lose their traditional medicinal system. Missionary conversions undermined faith in traditional practice: “They were beginning to not believe in the worth of their plants…in the ‘90s a lot of their plant knowledge had since disappeared.”

Often this came with negative health consequences; as teeth blackening fell out of favor, cavities became much more common. As acculturation deepens, the clock is ticking on this knowledge, as wisdom preserved for decades starts to wither and disappear. The least we can do is meet the rest of the world halfway and preserve our own pocket of medical botany on our campus.

In my experience, learning from plants is a process that cannot be purely an intellectual pursuit––it is tactile, visual, olfactory, all of your senses contribute to understanding. And so, according to Elvin-Lewis, we should install our own slice of the ethnobotanical world with a garden, a garden including medicinal plants from across the continent. And she has developed a plan.

There are 24 plants included on Elvin-Lewis’s “Eclectic Garden” list, plants from native medical traditions across North America. Some of these, you have likely heard of: Floridians like me will be familiar with the saw palmetto, and most students will have seen the purple coneflower flanking the campus along Forsyth. Others are more obscure, though it does not take an expert to figure out what “pukeweed” is used for.

With appropriate conditions to grow plants from across the continent, we are well positioned to take advantage of some of the richest ethnobotanical traditions in the world. Surely, as the professor emphasized to me, there is room on campus, instead of “more grasses and stuff.”