Will Medicine Survive the Anthropocene?

Up to ten percent of major drugs contain plant-derived ingredients, but a warming world could put those—and other medicines—at risk

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A man walks by a botanica, a store stocking medicinal plants, in Chicago. Alex Cheek/Flickr CC BY-SA

You’ll find them all over New York and other American cities: Botánicas, retail stores that are common in Latino communities with Caribbean ties. These are no mere bodegas. They’re packed with ritual-ready statues, candles, incense and amulets. But the real star of the show is the herbs. Whether they’re dispensed from an olden-timey glass jar or doled out in a plastic packet, botanicas are filled with, well, botanicals—plants that have been used as medicine by the Caribbean’s indigenous peoples for centuries. 

“These plants as medicines are important to people,” Ina Vandebroek, an ethnobotanist who heads up the Caribbean program at the Institute of Economic Botany of The New York Botanical Garden, tells Smithsonian.com. In places like the Bronx, some immigrants from the Dominican Republic and other members of the Caribbean diaspora still rely on botánicas as a first-line form of healthcare. They use ingredients like prickly pear to treat stomach ailments and cat’s claw for arthritis. It's easy to be skeptical, but in many cases, there’s something to the use of those herbs and scores of others found in traditional Caribbean remedies. In clinical studies, both prickly pear and cat's claw were found to have beneficial effects similar to the ones they were known for in indigenous settings.

Contrary to some perceptions, folk medicine is more than pseudoscience. “The traditional ethnobotanical knowledge from these indigenous cultures is responsible for many of the drugs that we have today,” Thomas Carlson, associate teaching professor at the University of Berkeley’s department of integrative biology and the curator of ethnobotany at the Berkeley Natural History Museum’s University & Jepson Herbaria, tells Smithsonian.com. Berkeley holds over 2 million botanical specimens from all over the world, many of which inspired or are used in present-day pharmaceuticals. 

There’s no knowing how quickly early humans learned to turn indigenous plants into medicines. By the time humans could record history, they already had apothecaries responsible for categorizing, compounding and dispensing herbal medicines. Like the University & Jepson Herbaria and the botánicas, apothecaries had quite the plant hoarding habit: The word “apothecary” itself derives from an ancient Greek word for storehouse. Medicine men, healers and spiritual practitioners also made use of a variety of indigenous and imported medicinal herbs, occupying various positions of renown and respect in their respective cultures. 

In the West, apothecaries practiced alongside alchemists and, eventually, early chemists. The mid-19th century teemed with technological promise. Fueled by cheaper printing presses and newfound distribution systems, it became practical for apothecaries to mass-produce and ship their secret formulas wholesale. The new ability to concentrate plant extracts led to plant-derived patent medicines like quinine (from cinchona tree bark) and morphine (from poppies). 

Then came a series of breakthroughs: German chemists figured out how to synthesize salicylic acid. What sounds like a synthetic itself is actually the component that gives willow bark extract its ability to ease pain and fever. Chemists at Bayer eventually determined a way to chemically mimic one of salicyclic acid’s relatives, acetylsalicyclic acid—more commonly known as aspirin. The synthetic age had begun, and today plant-derived synthetics can be found all over medicine shelves. Some drugs discovered in the lab have even been found in nature, where they existed all along. Case in point: Years after discovering the analgesic tramadol, scientists tracked down the drug’s active ingredient in the root bark of an African plant, too.

Despite the availability of synthetics that mimic the active ingredient of nature’s best cures, today many medicines still actually contain phytochemicals, or compounds found in plants. It’s estimated that at least ten percent of major drugs sold by major drug companies contain major compounds that are still derived from plants. Some, like the active ingredient in quinine, which is still used to treat malaria, can’t be effectively synthesized. And that’s not to mention the plants used in herbal remedies like the ones you could find in a health food store or botánica.   

Will Medicine Survive the Anthropocene?
Aspirin's active ingredient is a relative of a compound first identified in willow bark. Sage Ross/Flickr CC BY-SA

So what happens when those plants go away? “Climate change will impact species and ecosystems all around the world,” says Carlson. As the Earth warms and precipitation levels change, plants may be displaced or lost forever.

And pharmaceutical companies who rely on phytochemicals to make medicines won’t be the only victims of such changes. Carlson, who helps integrate indigenous perspectives into ethnobotanical research, tells Smithsonian.com that though local, rural populations contribute least to climate change, they run the risk of being most affected when their traditional healing methods disappear.

“They're really the least responsible, yet they’re the most vulnerable,” he says. Indigenous people can’t just pack up and leave their ancestral lands when climate change occurs—and if they did so, they’d leave behind the centuries of traditional medical knowledge they’ve acquired. “Local indigenous communities are tremendously knowledgeable in ecology and plant identification,” Carlson adds. 

Though it’s clear that Earth’s climate is changing, those changes can be hard to detect. Different shifts occur at different speeds, and shifts in plant range can take a long time to detect. For ethnobotanists, there’s no time to lose in cataloging and studying how humans use plants: It now appears that global warming is starting to speed up.

Given that up to 80 percent of the world’s population relies on herbal medicine as a primary source of healthcare, that’s of real concern to scientists. In places like India, 93 percent of traditional medicinal plants are already threatened. And though the problem is less significant in places like Europe, where a recent assessment found that “only” two percent of medicinal plants are threatened with extinction, rising temperatures could change that balance quickly.  

Will Medicine Survive the Anthropocene?
A holistic medicine center in Macau, China. Harvey Barrison/Flickr CC BY-SA

Both Carlson and Vandebroek predict that climate change will cause native species to move or go extinct. But both also point out that solutions to these issues can be found in indigenous cultures themselves. Local indigenous communities “could help academics and government agencies with strategies and solutions for ecosystem management,” says Carlson. By using fire management practices based on traditional methods developed by indigenous communities, for example, governments could reduce the frequency of devastating fires while helping preserve native habitats.

Indigenous people have something powerful in their arsenal against climate change, points out Vandebroek: creativity. When she studied the use of Antigonon leptopus, also known as coral vine or bee bush, in Jamaica, she learned that city dwellers use the invasive species to treat the common cold. In more intact mountainous areas where the species is present but not sprawling, however, things were different. “People didn’t have a name for it and they didn’t have a use for it,” says Vandebroek. Just as weeds adapt to their changing climate, it turns out, so do people.

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