Med students have to learn about a vast amount of drugs in medical school and are expected to know about them. You might be surprised how many medicines were actually derived from nature. Many know that aspirin is derived from willow bark, but few realize just how many other medications are derived from plants.

A number of very common and useful medications employed today have extremely interesting histories and were taken from nature. I am a medical student myself, and I hope you find the origins of these medications to be as fascinating as I do.

10 Cannabis Sativa And Dronabinol

The Cannabis sativa plant has been part of the recent controversy regarding the legality of marijuana. While marijuana is most commonly associated with the cannabis plant, there is another extremely useful pharmaceutical that has come from it.

Many know the symptoms of marijuana intoxication, including red eyes, dilated pupils, dry mouth, increased appetite, slowed reaction time, euphoria, dizziness, shallow breathing, and increased heart rate. While some of these symptoms seem unappealing, the medical community has found others to be useful in treating certain populations of patients.

The drug dronabinol has been created as a synthetic form of THC to utilize some of marijuana’s side effects. There are various uses for the drug, but most commonly, it is used as an appetite stimulant for patients with AIDS and as an antiemetic in patients receiving chemotherapy.^[1]

While there has been some controversy regarding the use of dronabinol, it has been shown to be minimally harmful with a low potential for abuse. Who knew that giving someone the munchies could be so beneficial?

9 Podophyllum Peltatum And Etoposide

The Native Americans have recorded using the plant Podophyllum peltatum as a purgative, antiparasitic, and cathartic hundreds of years before its usefulness was officially recognized. Interestingly, the Penobscot people of Maine even appeared to be using it to treat “cancer.” The Iroquois additionally used it to treat snakebites and as a suicide agent. Despite this, the medical use for P. peltatum was not official in the United States until 1820 and not until 1861 in Europe.

Hartmann Stahelin was a Swiss pharmacologist who had made large contributions to the cancer therapy field. He had a particular proclivity for biomedical sciences and was recruited to lead the pharmacology department in Basel in hopes of researching cancer and immunology in 1955.^[2]

Once in Basel, he lead the discovery of various antitumor agents from P. peltatum, also known as mayapple. Initially considered by chemists to be “dirt,” Stahelin noticed that a particular extract from the Podophyllum plant had interesting properties. After purifying this compound, it was found to be a new class of antitumor medication.

Named etoposide, the medication works by stopping the tumor cells’ ability to divide. It blocks a specific enzyme that cells need in order to replicate. Therefore, rapidly dividing cells such as cancer cells are heavily affected. Currently, etoposide is used to treat various cancers, especially that of the lung, and can be thanked for saving many lives.

8 The Calabar Bean And Physostigmine

The Efik people from the Akwa Iborn State, or modern-day Southeast Nigeria, were the first to be in contact with physostigmine from the calabar bean (Physostigma venenosum). Use of the calabar bean was very common in Efik culture as an ordeal poison for those accused of witchcraft. The milky extract of the bean was given to the accused, and if they died, the accusation of witchcraft was confirmed. If they lived, usually due to vomiting the poison out, they were declared innocent and set free.

Missionaries wrote about the Efik’s use of the calabar bean, and some of the beans found their way back to Scotland.^[3] In 1855, a toxicologist named Robert Christison decided to test the poison’s toxicity by consuming a bean and surviving to document what he experienced.

It was studied throughout the 1860s, most notably by Douglas Argyll Robertson, who was the first to use the calabar bean extracts medically and recorded its effects on the pupil. The most potent component from the calabar bean was finally isolated and named physostigmine by Thomas Fraser. In 1867, Ludwig Laqueur tested the extract on himself and used it to successfully treat his glaucoma. By the 1920s, Otto Loewi discovered the neurotransmitter acetylcholine and found that the calabar bean extract worked by increasing that neurotransmitter, having profound effects on the parasympathetic nervous system.

Medically, physostigmine does increase the amount of the neurotransmitter acetylcholine by blocking the enzyme acetylcholinesterase, which breaks it down. It is especially useful in treating the disease myasthenia gravis and has been more recently used to treat Alzheimer’s, as it has the ability to cross the blood-brain barrier.

7 Meadow Saffron And Colchicine

The use of the plant Colchicum autumnale, or meadow saffron, for medical problems has been recorded as far back as 1500 BC on the ancient Egyptian Ebers Papyrus for rheumatism and swelling. Since then, C. autumnale has been a treatment for other maladies such as gout, familial Mediterranean fever, Behcet’s disease, and pericarditis. It works in a similar way to Taxol, as it blocks microtubules.

As early as the first century AD, C. autumnale was being described as a treatment for gout by Pedanius Dioscorides. Gout is a type of arthritis characterized by needle-shaped crystals building up in the joints, causing sudden pain attacks, swelling, and redness. Others, such as Alexander of Tralles, Persian physician Avicenna, and Ambroise Pare have also recommended C. autumnale as a treatment for gout. Colchicine itself was isolated from C. autumnale in 1820 by French chemists P.S. Pelletier and J.B. Caventou. It was later purified by P.L. Geiger in 1833.^[4]

Despite its long history of being effective, colchicine actually had no FDA-approved prescribing information, dosage, recommendation, or drug interaction warnings until as recently as 2009.

6 Indian Snakeroot And Reserpine

Rauwolfia serpentina (Indian snakeroot or sarpagandha) is a plant that was known in India for its medicinal purposes long before its discovery by the Western world. Georg Rumpf, a botanist with the Dutch East India Trading Company, first noticed the plant in 1755 during his travels. He recorded it as being used as a treatment for insanity in South Asia. Extracts from the roots of the Indian snakeroot were sold cheaply in markets all over India as pagalon ki dawa, or “drugs for the mad.” In addition, it was also used by mothers in Eastern India to put their crying babies to sleep as well as a treatment for labor, snakebites, fever, and intestinal problems. Mahatma Gandhi reportedly used extracts from the roots as a tranquilizer as well.

By the early 20th century, India undertook efforts to standardize and research the pharmacologic properties of sarpagandha. Professor Salimuzzaman Siddiqu began systematic research on the active constituents of the roots and root bark in 1927. Dr. Kartick Chandra Bose and Gananath Sen, two leading physicians from Calcutta (now called Kolkata), also independently noted the use of the extract to treat high blood pressure and insanity. Dr. Rustom Vakil, known as the father of modern cardiology in India, popularized the use of the plant to treat high blood pressure.

Isolated in 1952 from the dried root of R. serpentina, reserpine quickly became popular in Western medicine. It became the first drug ever to successfully show antidepressant properties in a randomized placebo-controlled trial.^[5] Though it is rarely used today due to its immense side effect profile, it was critical in furthering our understanding of the role of neurotransmitters in depression and blood pressure.

5 Indian Hemp And Pilocarpine

As settlers began coming to the New World in the early 1600s, they noticed that the indigenous tribes of Brazil had a vast knowledge of the medicinal uses of local plants. One plant in particular, Pilocarpus jaborandi (Indian hemp), was used to treat a variety of maladies but most commonly for fever. It was found that the leaves could trigger profuse sweating, salivation, and urination as a way to rid the body of toxins. The name jaborandi even comes from the Tupi translation for “what causes slobbering.”^[6]

In the 1870s, P. jaborandi was incorporated into Western medicine and became a popular treatment for intestinal problems, lung problems, fever, skin issues, kidney disease, and edema in Europe. Surprisingly, the plant was also found to be an effective antidote to deadly nightshade poisoning. By 1875, pilocarpine was isolated from the plant and found to be the main culprit behind its effects. This was discovered almost simultaneously by two different researchers, one in France and one in England.

Pilocarpine was soon found to be an extremely effective treatment for glaucoma by decreasing the pressure in the eye. Even today, it remains a very popular and widely used treatment for glaucoma as well as a means to induce perspiration when trying to diagnose cystic fibrosis. Laboratories still haven’t been able to fully replicate and synthesize the pilocarpine found in P. jaborandi. This plant remains one of Brazil’s largest and most important exports.

4 The Pacific Yew Tree And Paclitaxel

Researchers are continuously searching for new and innovative ways to fight cancer. Sometimes, the treatments that they are searching for may be much closer to home than they realize. In 1955, the National Cancer Institute created the Cancer Chemotherapy National Service Center (CCNSC) in hopes of finding new cancer treatments. In the 1960s, the CCNSC looked to partner with the US Department of Agriculture to search for these cures within nature. Over the course of about 20 years, 30,000 natural plant and animal products were tested.

Out of the 30,000 samples, one was found to be pivotal in the treatment of cancer. Two researchers, Dr. Monroe Wall and Mansukh Wani, discovered that the extracts from the bark of the Pacific yew tree (Taxus brevifolia), indigenous to the Pacific Northwest, were toxic to tumor cells.^[7] Later, it was found that the toxic compound is actually synthesized by a fungus within the bark. Thus, the new chemotherapy drug known as paclitaxel was born.

Paclitaxel (brand name Taxol) is commonly to treat breast and ovarian cancer. Medically, it works by blocking microtubules, which basically stops the cancer cells from being able to divide and grow. Since its discovery, paclitaxel has become a big part of cancer treatment and saved millions of lives.

3 Deadly Nightshade And Atropine

Atropa belladonna, commonly known as belladonna or deadly nightshade, is an herb that has been used for many centuries by many people to treat a wide variety of maladies. The plant is native to Europe, North Africa, and West Asia but has been more recently introduced to Canada and the United States. Prior to the Middle Ages, the herb was used as an anesthetic for surgery. Its deadly toxicity enabled its use as a poison for political enemies or on the tip of an arrow by the military in ancient Rome.

During the Middle Ages, the deadly nightshade plant became very popular for cosmetic purposes. Venetian women would use it to redden the pigment of their skin as a type of blush. Another common use for the herb was for dilating the pupils of women in order to make them more seductive and attractive. The herb obtained the name belladonna, meaning “beautiful lady,” exactly because of this use. Despite these more benign functions, many quickly became aware of the herb’s more deadly abilities. It was later utilized by assassins and criminals as well as witches to make poison.

Despite years of its use as a poison and cosmetic, it was soon realized that A. belladonna had more of an ability to help than previously realized. It could be used as a pain reliever, muscle relaxant, anti-inflammatory, whooping cough treatment, and hay fever treatment. In the 1930s, the therapeutic component of belladonna, known as atropine, was isolated.^[8] Belladonna, by itself, does not have approved medical uses, but atropine has since become an extremely useful medication in the medical community.

Atropine is known as an anticholinergic, meaning it blocks the effects of the neurotransmitter acetylcholine. Its mechanism of action is basically opposite to that of physostigmine. Because of this, atropine can cause pupil dilation, increased heart rate, and decreased secretions. In addition to its uses of raising heart rate and decreasing saliva prior to surgery, it can also be used to reverse certain overdoses. Various derivatives of atropine have also been developed for other medical uses. For example, tiotropium and ipratropium bromide are used in various lung disorders.

2 The Cinchona Tree And Quinine

Found in the bark of the cinchona tree in South America, quinine was initially used by the Quechua as a muscle relaxant.^[9] It was then brought to Europe by the Jesuits, and by 1570, the Spanish had become aware of the cinchona bark’s medicinal properties. Nicolas Monardes and Juan Fragoso recorded that it could be used as a treatment for diarrhea. Despite the varied ancient uses for quinine, the big discovery for its use came in the early 17th century.

The marshes and swamps surrounding Rome in the early 17th century were teeming with malaria-ridden mosquitoes. Malaria is a mosquito-borne infection caused by parasitic protozoans. Symptoms include fever, fatigue, vomiting, headache, jaundice, seizures, and eventually death. Malaria lead to the deaths of many popes, cardinals, and citizens at the time. Agostino Salumbrino, a Jesuit apothecary, had seen the cinchona bark being used for the shivering phase of malaria. At the time, Salumbrino did not know that the bark’s effect on malaria was unrelated to its effect on rigors, but regardless, he brought it to Rome.

Over the years, cinchona bark became one of the most valuable exports from Peru, even curing King Charles II. In 1737, Charles Marie de La Condamine discovered the most potent component of cinchona bark, and it was later isolated by Pierre Joseph Pelletier and Joseph Caventou in 1820. The extract was was named quinine, based on the Incan word quina, meaning “bark” or “holy bark.”

Large-scale malaria prophylaxis with quinine began around 1850. The drug actually played a very significant role in African colonization by Europeans. In the early 19th century, Peru tried to outlaw the export of cinchona bark, seeds, and saplings to maintain their monopoly. Fortunately for the world, the Dutch were successful at growing the tree in their Indonesian plantations and soon became the main supplier.

During World War II, the Allies were cut off from quinine when Germany conquered the Netherlands and Japan controlled Indonesia and the Philippines. The United States was eventually able to obtain four million seeds from the Philippines, but not before thousands of Allied troops died from malaria in Africa and the South Pacific. Thousands of Japanese troops also died despite their control, due to ineffective manufacturing of quinine.

Since its discovery, quinine has played a role in saving millions of lives as well as having major effects on wars, colonization, and history in general. It has since been replaced as the first-line treatment for malaria by newer drugs in 2006 by the World Health Organization. Quinine can also be used for other diseases, such as babesiosis, restless leg syndrome, lupus, and arthritis.

1 Foxglove And Digoxin

Digoxin was once a mainstay treatment for heart failure and arrhythmia. It works by slowing the patient’s heart rate but increasing the heart’s contraction intensity. Unfortunately, the drug has a very narrow therapeutic index, meaning that it can be extremely easy to overdose, with disastrous effects.

Digoxin’s discovery by Scottish doctor William Withering occurred in 1775 . He was working as a physician when a patient came to him suffering from a bad heart condition. Withering had nothing to offer the man, as there was no acceptable treatment for heart failure at the time. Thinking he was going to die, the patient went to a town gypsy and miraculously improved after being given an herbal remedy.

After seeing this, Dr. Withering searched for the gypsy, eventually finding her and demanding to know what was in her remedy. After Dr. Withering bargained with the gypsy, she finally revealed many things within the remedy, but Digitalis purpurea, or foxglove, was the main ingredient. The potency of foxglove was already well-known, as it had been used as a poison in medieval trials by ordeal as well as externally applied to heal wounds.

Withering immediately went to work testing variations of the foxglove extract on 163 patients. He eventually found that dried, powdered leaves gave him the most successful results, and it was first officially used in 1785.^[10] Even though it is not as commonly used now, digoxin was revolutionary in its ability to help those with heart failure.

+ Chondrodendron Tomentosum Vine And Tubocurarine

For centuries, South American natives used poison from the Chondrodendron tomentosum vine to hunt animals. When Spanish conquistadors returned from the New World, they spoke of a mysterious “flying death.” In 1516, Peter Martyr d’Anghera, a chronicler, wrote of these tales in his book De Orbe Novo for King Ferdinand and Queen Isabella. Sir Walter Raleigh visited Venezuela in 1594 and also recorded the use of the poisoned arrows in his book Discovery of the Large, Rich and Beautiful Empire of Guiana. One of Sir Raleigh’s lieutenants referred to the poison as ourari, which later became various European renderings, one of which was “curare.”

Further exploration of South America was put on hold until the 18th century due to wars. A physician named Edward Bancroft traveled to South America for five years and was able to bring back some samples of curare. Sir Benjamin Brodie then used his samples on small animals. He was able to keep them alive after inflating their lungs with bellows. Charles Waterton moved to South America in 1804 and obtained some ourari from a local tribe. In 1814, he demonstrated its effects on three donkeys to an audience that included Sir Benjamin Brodie. The first donkey had its shoulder injected with the extract and died immediately. The second had it injected under a tourniquet on its leg and lived until the tourniquet was removed. The third died after its injection but was revived with bellows and went on to survive.

Curare was found to work at the nerve-muscle junction after Claude Bernard’s experiments on frogs. Further research on curare discovered that it had potential as a muscle relaxant for patients under anesthesia. Curare-like compounds were created, mirroring the original isolated curare. Today, these compounds are vital to almost all procedures involving anesthesia. The drugs work by causing complete skeletal muscle relaxation during surgery or mechanical ventilation as a part of the general anesthesia protocol.^[11]

Shelby is currently a third-year medical student. While she doesn’t have much free time anymore, she still loves writing top 10 lists when inspiration strikes.

Advances in bio-engineering have made it theoretically possible to do just about anything to plants. In fact, many of the plants we have today have already been modified beyond all recognition from what they used to be. Carrots were originally white, scrawny roots; peaches were salty and cherry-sized; watermelons were small and bitter; and eggplants looked like eggs.

Our world — or at least our supermarkets and gardens — would look different without genetic modification. However, GM crops also carry significant drawbacks, and for all their promise to help us out of our messes, it’s clear how they land us in more.

Still, here are some of the most inventive and audacious ways humans won’t leave well enough alone.

10. Super air-purifying pothos

Typical of humans, our fuel-guzzling approach to purifying air with electrical air purifiers only compounds the problem. To provide an alternative, French company Neoplants has genetically modified a pothos (Devil’s ivy) plant right down to its roots to recycle airborne pollutants. They call it Neo P1 and, apparently, it is “capable of doing the air-purifying work of up to 30 plants.”

Plants are naturally better at absorbing and metabolizing volatile organic compounds (VOCs), but Neo P1 has been tweaked to excel — specifically targeting indoor VOCs like benzene, ethylene glycol, formaldehyde, and toluene. Nothing is wasted; the compounds are broken down and recycled into the water, sugars, and amino acids Neo P1 needs to grow, along with oxygen to release into the air. To boost its efficacy, the roots of the plant also have genes from extremophile bacteria (bacteria that have evolved to survive inhospitable environments by feeding on toxins). 

As the name of their first plant implies, Neoplants hope to create more air-purifying plants in the future. They also see their work as helpful in the “fight” against climate change.

9. Nitrogen-fixing crops

Rightly or wrongly, we’re obsessed with dietary protein. And legumes (beans, pulses, peanuts) are among the best plant sources of all — owing not only to how much protein they have but also to how they produce it.

Protein requires nitrogen, the bioavailability of which (i.e. the supply for use by organisms) is limited — hence its addition to fertilizer. Unlike most plants, however, legumes pluck it straight from the air. This is called ‘nitrogen-fixing’. Genetically modifying other staple crops to do the same would revolutionize agriculture around the world, especially in poor countries, by eliminating the need for expensive, climate-worsening fertilizers.

Critics say it’ll take a long time, though, and point out the existing problems of GM crops — such as herbicide-tolerant weeds. And obviously there are other, more direct ways to alleviate global poverty.

8. Cocaine tobacco

This one’s a game-changer in an indirect way. Don’t expect to see your local dealer offering a special new type of shiny white tobacco. Researchers were interested in genetically modifying plants to produce cocaine to study its evolution as a pesticide and its potential applications in medicine. 

Cocaine production in coca plants has long been veiled in mystery, in part because of how labor-intensive it is to grow coca in a lab. The answer scientists in China came up with was to genetically reconstruct, in a tobacco plant’s genome, the biochemical pathway by which cocaine is produced. Some parts of the chain they left the tobacco plant to come up with itself, and the result was tobacco leaves containing cocaine. The implications for finding new medicines are significant.

According to the researchers, the amount of cocaine produced wasn’t enough to make it a viable black market enterprise and, in any case, the process is too technical for the average clandestine drugs lab. However, the researchers themselves are working on it, hoping to ramp up the tobacco plant’s output.

7. Scorpion venom cabbage

Genetic modification and pesticides are two of our most toxic contributions as a species. So why not combine them into one? In a bid to consolidate the damage we’ve done, scientists took the venom gene from deadly scorpion tails, engineered it to only kill insects, and put it in a cabbage. What could go wrong? 

Although early tests confirmed no toxicity to humans, the concept is riddled with problems. For one thing, the study tested human breast cancer cells in vitro, not healthy human cells in vivo. Furthermore, the cabbage itself could be harmed. The genetic modification could escape and infect non-GM specimens. And, as with existing pesticides, it could destabilize whole ecosystems. 

The FDA has a long track record of ignoring such issues when approving GMOs, though — even when they contribute nothing. In this case, since the pesticide effect of venomous cabbage depends on insects actually eating it, it’s likely that farmers would also use pesticide sprays just to keep insects at bay. In other words, consumers would get double the toxins.

6. Endospore oak

Oak trees are, to the scientific mind, intolerably inefficient. Not only do they produce far more acorns than ever take root, but they waste millions of cells by shedding their leaves every autumn. What if, instead of rotting away on the ground, those cells transformed into millions of spores, spread by the wind, each capable of cloning their source. This would be a superior evolutionary strategy, and there is, apparently, “no biological principle … forbidding … [reproduction] by both spores and seeds.” And, unlike acorns, endospores can remain viable for millions of years.

Again, though, there are serious problems. Endospore oak trees are one thing, but what about endospore knotweed? Unless this particular genetic modification is strictly limited to “beneficial plants” (and even then), “superweeds may overrun the Earth.”

As usual, just because we see a gap in the market, so to speak, doesn’t mean we ought to exploit it. After all, trees would also be more efficient if they evolved to “walk” faster than they already do, and if they learned to hunt with poison gasses or spikes. It’s just not the kind of world most of us want.

5. Supernutritious fruit and veg

Genetically modifying plants to provide more nutritional value is nothing new. We already have protein-boosted potatoes, corn, and rice; linseed with higher levels of omega-3 and -6; tomatoes with snapdragon antioxidants; and lettuce with more digestible iron. There are also carrots that increase our calcium absorption, and the so-called “golden banana,” an Australian frankenfruit splicing the common banana with an orange Papua New Guinean variety high in provitamin A. Typically, however, human interference is the reason for low nutrition in the first place. So we’re skeptical.

Scientists hoping to revolutionize our crops by 2028 put their faith in super-accurate CRISPR-Cas9 gene editing. The possibilities are many (and stupid): beans that taste like chicken nuggets; carrots that taste like potato chips; potatoes with hamburgers in the middle; and sunflower seeds the size of small eggs to be eaten like apples. 

Some of the less childish ideas include hypoallergenic peanuts and lentils with as much protein as meat. But they all raise questions of how much control humans should have over nature, especially considering the mess we’ve made as it is.

4. Pollution-eating poplars

Phytoremediation is the process by which some plants clean up pollution — drawing contaminants up through their roots, breaking them down into harmless byproducts, and either using them or releasing them in the air. It’s another way plants have been pressed into service undoing the damage we’ve done. But, scientists say, they don’t do it well enough. They’re too slow.

The solution has been to genetically modify poplars to break down trichloroethylene (TCE) more efficiently. TCE is the most common groundwater contaminant found at the most polluted sites in America. Once promoted by the pharmaceutical industry as an anesthetic, it’s now a known carcinogen that lingers for a long time in the air, water, and soil wherever it’s used. And, given its continuing use in many household cleaning products, it’s a problem that’s only getting worse. 

The research into genetically modified phytoremediation is promising, though. Whereas unmodified poplars removed just three percent of TCE from a solution, poplars boosted with additional enzymes from rabbit livers removed as much as 91 percent. They also fared better, not withering as usual but actually growing more robustly. And it’s not just TCE they can deal with but a suite of other chemicals, including vinyl chloride (used to make plastics) and benzene (an airborne pollutant from petroleum).

3. Vaccine banana

The (artificially inflated) cost of vaccines means the Third World often doesn’t get them, and kids keep dying from easily preventable diseases — like diarrhoea. One solution scientists have come up with is to genetically modify crops to include the vaccines in their genome. 

An early proof of concept successfully delivered hepatitis B antigens to rats from specially engineered potatoes. However, since potatoes aren’t eaten raw, the research switched to bananas. Not only are they cheap, they’re also a well established crop in “developing” countries. And just 10 hectares of vaccine banana plantation would, they say, be enough to vaccinate all children in Mexico under the age of five.

Properly administering a vaccine banana isn’t as simple as peeling the skin and eating it, though. The plan is to purée the fruit and bottle it up (10 doses per bottle) to ensure each patient gets the right dose. Other crops scientists have experimented with include lettuce, carrots, and tobacco.

 2. DARPA’s intelligent trees

In 2017, the Defense Advanced Research Projects Agency (DARPA) put out a call for proposals to its Advanced Plant Technologies (APT) program. They’re specifically interested in genetically modifying plants to “gather intelligence” about, for example, environmental pathogens and radiation. Detecting the presence of whatever they’re designed to, the “sentinel plants” would “report” via “discreet response mechanisms” such as subtle changes in leaf color. 

Unlike sophisticated hardware, plants offer stealth, easy distribution, and energy independence. And the concept has already been proven. In 2011, researchers successfully engineered a TNT-detecting plant, the leaves of which would de-green in the presence (in soil or air) of TNT molecules. And all plants naturally respond to their environment through an input/output dynamic comparable to that of computers. Like bomb-sniffing dogs, it’s really just a case of training natural mechanisms to better serve the military.

However, DARPA wants to take things further, beyond simple on/off bio-computing to more nuanced detection and reliable, detailed reporting. They even expressed an interest in engineering plants to pick up on electromagnetic signals.

1. Dyson tree

You’ve probably heard of the Dyson sphere. Proposed by physicist Freeman Dyson, it’s a hypothetical structure built to enclose a star and capture its energy. Less well known is the Dyson tree. Genetically engineered for space, with thick glass bark to allow sunlight in and stop heat escaping, this hypothetical plant would be seeded on a comet and create its own atmosphere. In theory, it could support a whole ecosystem — at least for a time — with the inside of the comet hollowed out for inhabitants and the comet’s ice and carbon providing everything the “leafy spaceship” needs.

If it seems like science fiction, that’s because it is. But it’s not beyond the realm of possibility. Plants like the voodoo lily and carrion flower do generate their own heat; in fact, the skunk cabbage generates up to 60 degrees Fahrenheit, which is enough to melt frozen ground around it. 

There’s also no shortage of comets. The Kuiper belt past Neptune, which has trillions of comets, could potentially be seeded with enough Dyson trees to become a cosmic “archipelago of city states”. A Dyson tree comet the size of Manhattan could support millions of humans alone. And, with little gravity, not only would it be easy to hop between comets, but structures on each could be taller than on Earth.

They say the truth is stranger than fiction and while that may not always be true, sometimes the real world is more than willing to throw a few curveballs our way. As an example, look no further than nature. Even something as simple as plantlife can become exceedingly bizarre and downright creepy when you start looking into it. 

10. The Vampire Tree

Have you ever been taking a walk through the woods and noticed a decrepit old tree stump just sitting there looking old and rotten? It happens all the time. But what you may not be aware of is that there’s a chance that dead tree isn’t dead at all. 

Researchers in New Zealand found the stump of a kauri tree in a forest and while the top looked dead, underground life was still stirring. The tree had long ago grafted its roots into a massive network of other roots that likely belonged to dozens, if not hundreds, of other plants and trees. Effectively creating a subterranean superorganism, this root network shared nutrients among all parts. Even though the tree had been destroyed and no longer had leaves by which to survive thanks to photosynthesis, the other trees in the network were able to share nutrients and keep that stump alive.

Though in an ideal situation, every member organism would contribute resources, the almost dead kauri tree had become a parasite, like a vampire, living beyond death by draining life from its companions. But it may also be contributing, allowing the flow of nutrients between all members to the benefit of the whole. 

9. Kudzu Smothers Everything

Most of us would never look twice at kudzu. It’s a leafy green vine that looks like any other plant you might expect to find in the background. But it doesn’t stay in the background for long. Kudzu is an invasive species that grows at an incredible rate. It came to the US in the late 1800s as an ornamental plant and has also been used for erosion control. It’s well suited for that jib because kudzu can grow up to a foot per day. Vines can reach 100 feet in length. 

When kudzu spreads, it covers everything. Soil, cement, walls, telephone polls, other plants. It covers everything as it takes over. And with any given vine growing one foot per day, it doesn’t take long. But it gets worse. Kudzu produces isoprene and nitric oxide. When those come into contact with nitrogen, which makes up most of our atmosphere, it makes ozone. 

Ozone is a dangerous chemical at ground level, and it can kill off other plants, not to mention animals. Kudzu causes a 50% increase in the number of days each year when ozone levels are considered unsafe by EPA standards. 

8. Acacia Trees Communicate Danger

Most of us know acacia wood from furniture or decorative wood items. It’s even used as a food additive sometimes. But there’s more going on inside acacia trees than you might think at first glance. 

German forester Peter Wohlleben has proposed a controversial idea in 2015: trees can talk. As we mentioned with the vampire tree, there is evidence that trees actually do function in groups, not as lone organisms. They share resources and are able to support each other. Tree roots connect with fungus underground and share signals between organisms. It’s theorized this includes things like warnings about insect attacks, for instance. Chemical signals from one tree to another can alert members of the greater colony. Nutrients are shared, which is how saplings, too small to reach the sunlight under the canopy of larger trees, are able to survive. But there’s much more.

If a giraffe starts eating the leaves of an acacia tree, the plant produces ethylene gas. This gas, when it reaches other acacia trees, causes them to start producing tannins in their leaves. Large quantities of tannins will make the giraffe sick. It could even kill it, so the giraffe is forced to stop eating. All because one tree was able to signal other trees. Even more bizarre is that giraffes know this. They graze with the wind, and walk ahead of the gas clouds because they have evolved to be aware that acacia trees do this. 

7. Fire Coral Fungus

There are thousands of species of mushrooms in the world and while some are edible and delicious, many are incredibly toxic. The symptoms can vary from mushroom to mushroom and often include things like vomiting, stomach pain, and diarrhea. Severely toxic mushrooms will cause organ failure and death. In that regard, fire coral fungus is like many of its mushroom cousins. But fire coral fungus can get much, much worse.

Most mushrooms need to be ingested to cause damage. Not so with fire coral. The mycotoxins it produces can be absorbed through the skin. And the damage it causes when eaten goes to a level far beyond most other mushrooms. Sure, there’s the unbearable pain and vomiting, but then there’s also hair loss, peeling of the flesh and even shrinking of the cerebellum. This can cause impaired movement, speech, and perception. If enough has been consumed, the victim can also expect to potentially suffer from necrosis and finally death as a result. 

Progression of symptoms is also a mixed bag. Some people showed no symptoms at all for weeks after eating the mushrooms before it hit them. 

6.  Shiinotomoshibitake Mushrooms Glow

Don’t feel out of the loop if you’ve never heard of Shiinotomoshibitake mushrooms, because almost no one has. If you head to Mt. Yokogura in Japan between May and July, you may get a chance to see them for yourself, though. They’re hard to spot during the day because they only grow a few centimeters in length. So if you really want to experience them, try hunting them down at night.

It turns out that the elusive Shiinotomoshibitake mushrooms emit light. At night they can glow a vibrant green color. They live on decaying tree trunks and will only glow during that certain time of year, so tracking them down isn’t all that easy, but it’s clearly worth the effort if you’re a fan of otherworldly vegetation.

5. Little White Mushrooms

It seems like something called a Little White mushroom has no business being dangerous and yet it’s been blamed for a massive number of deaths in China. If you include mold and yeast, there are over 50,000 kinds of mushrooms in the world and science has just not been able to study them all. That’s why the Little White mushroom is relatively unknown.

In the Yunnan province of China, there had been an ongoing mystery for 30 years. Every rainy season, people would die of cardiac arrest in numbers beyond what should be expected. The deaths were incredibly sudden, sometimes occurring right in the middle of a conversation. The government investigated for five years before they stumbled on an answer. 

Researchers looking into what they dubbed Yunnan Sudden Death Syndrome noted that many of the victims had the same mushrooms in their homes. After determining the mushroom was the likely cause, locals were warned to stop eating it. The number of mysterious deaths then dropped to none. 

Oddly enough, studies showed that, while the mushrooms were toxic, they were not toxic enough to kill. It’s believed something else, perhaps barium in the water, worked in conjunction with the mushrooms to kill. 

4. Toxic Black Walnut

Walnuts may not have the cache of an almond or a cashew, but they’re still fairly popular. And this despite the fact that walnuts want you and everything around you to die miserably.

If you’ve ever seen a walnut in the wild, you know that the nut itself comes off the tree encased in a green husk. The moment you begin to peel that husk to get the nut inside, an unpleasant smelling fluid emerges that turns brown fairly quickly. This is called juglone.

Inside the walnut, and the tree, juglone is called prejuglone. It’s clear and perfectly safe. But the moment it hits the air, it oxidizes and becomes toxic. The toxic juglone can kill both plants and animals. Very few animals can ingest it safely, and even plants that grew near a walnut tree will die as the roots of the tree leak the fluid, not to mention any leaves or nuts that fall from its branches.

Sensitivity to juglone varies, but it can be quite bad for some victims. Even contacting dust from walnut wood being cut near you can cause rashes and welts on the skin. Breathing it in can cause respiratory issues and eating it can cause symptoms similar to cyanide. 

3. Chernobyl Mushrooms

By now, everyone knows the basics of what happened at the Chernobyl nuclear power plant. There was an explosion in 1986 and it proved to be one of the worst disasters in human history. There remains a 1,000 square mile exclusion zone around the site. Many animals and plants returned to the area with no humans around, but their radiation levels remain high as a result. Among the wide variety of wildlife found in the area are a unique species of fungus.

What’s been called dark fungi has been known to grow in radioactive areas for some time. This mushroom, colored by melanin, doesn’t need the sun to provide energy. Instead, it seems to feed on the radiation, absorbing it and feeding on it in much the same way a green leafed plant would turn energy from the sun into energy to grow through photosynthesis. 

The melanin seems to shield the mushroom from the harmful effects of radiation and convert it to usable energy To test whether this was true, researchers bombarded fungus with gamma rays at 500 times the level they’d normally be exposed to. The fungus grew three times faster than normal as a result. 

2. Japanese Knotweed

If you’ve ever seen a plant growing out of a crack in the pavement, you may have paused to wonder how it accomplished that task. You might assume that the pavement cracked due to weather or shifting earth and the plant took advantage of the opening. But that isn’t how Japanese Knotweed works. This plant can grow almost anywhere and will break through cement and stone along the way.

Knotweed can live for up to 20 years in places with no light. It can sprout under paved roads and burst through and even grow in stone walls. It’s already causing about $212 million per year in damages and will probably only get worse in the future. 

The plant is native to volcanic areas in Japan. It evolved to survive being smothered by volcanic rock, able to continue to grow in the dark and trapped by stone. When you try to remove it, the plant actually becomes more aggressive, growing even faster as a result. The roots can grow up to 10 meters from the stem, making it nearly impossible to kill. 

1. The Piranha Plant

There aren’t a lot of famous plants in the world. Audrey II from Little Shop of Horrors qualifies. And maybe The Giving Tree. And if you’re a gamer, you surely know about the Piranha Plant from the Super Mario series of games. Turns out we have one of those in the real world, too. Or at least a visually similar cousin.

The plant reproduces by luring in insects that eat dung. They are attracted to the smell, go inside and get trapped. The flower then releases pollen and sets the bugs free, covered in pollen, to spread its spore around town.

Known as hydronora africana, this parasitic plant can look like the piranha plant or just an alien mouth if you catch it at the right phase of its life. According to scientific sources, the plant has an unpleasant odor. According to less scientific sources, it smells like poop. It also produces edible fruit, which is said to taste like a potato. 

The once routine act of dining out has presented a conundrum for hungry customers living in the Covid age. Has my server been vaccinated? What about the cooks? Did the busboy just sneeze?! 

Alternatively, we can eliminate human contact altogether by foraging fresh produce in the wild. However, one must be extremely careful — eating the wrong plants could result in a trip to the emergency room or even a date with the grim reaper. 

7. Belladonna

Its name means “beautiful woman” in Italian. However, don’t be fooled. This lady is a killer in disguise and commonly known by a more apt nickname: Deadly Nightshade. 

Belladonna is a highly toxic perennial herbaceous plant in the Solanaceae family, featuring bell-shaped purple flowers and shiny blackberries. The shrub is native to Europe, North Africa, and Western Asia and can be found in woodland areas and along paths and river banks.

The plant’s root is generally the most toxic part and contains tropane alkaloids, which cause paralysis in the body’s involuntary muscles, including the heart. Belladonna also has a celebrated history of usage as a medicine, cosmetic, and poison. 

For example, during the Renaissance, women used the juice of the berries in eye drops to dilate the pupils for the intended purpose of making the eyes appear more seductive. In ancient Rome, the extract was widely used as a poisonous elixir — and allegedly used by Roman empress Livia Drusilla to murder her husband, Augustus.

6. Elderberries

This seemingly innocuous tart fruit is loaded with vitamins and antioxidants and can be found in various products, including jams, wines, and health remedies. Hippocrates, “The Father of Medicine,” called the Elder tree his “medicine chest.” Nonetheless, consuming uncooked or unripe berries may leave you feeling much worse, causing severe diarrhea, seizures, and even death. 

The most common type of this deciduous shrub is the Black Elder (Sambucus nigra). Reaching up to 30 feet tall, the tree is native to Europe but is also widely grown in other regions of the world. 

In addition to producing the dark berries, the Elder yields clusters of small white or cream-colored flowers known as elderflowers. Unfortunately, the seeds, stems, leaves, and roots of the Black Elder contain potentially fatal levels of a cyanide-producing glycoside. In extreme cases, the poison prevents the cells in the body from using oxygen, causing the major organs of the victim to shut down. 

5. Giant Hogweed

History Channel’s hit reality TV show, Alone, features contestants surviving on their own in the wilderness for a shot at winning $500,000. Ostensibly, it’s a challenge of out-starving the competition while trying to avoid being eaten by even hungrier bears. During the filming of season eight, one of the cast members contracted food poisoning after ingesting cow parsnip, an edible but toxic plant if not properly cooked. The foliage is also easily mistaken for a much more dangerous plant: Giant hogweed.

Merely touching this weed (Heracleum mantegazzianum) can lead to phytophotodermatitis, a severe skin inflammation. The sap covering this herbaceous flowering plant contains toxic chemicals known as photosensitizing furanocoumarins, which react with light when in contact with human skin. Painful blistering typically occurs within 48 hours, and if sap gets into a person’s eye, the reaction can lead to blindness. 

The invasive species has become a serious concern throughout North America as it continues to spread in rural and urban areas. Contact with the plant’s watery sap should be avoided unless equipped with protective outerwear, goggles, and rubber gloves. 

4. Hemlock

Famously (though dubiously) chosen by Socrates as the means of his own execution, hemlock is common worldwide — often growing by the side of the road. Other names include devil’s flower, scabby hands, and break-your-mother’s-heart. Its taxonomic name derives from the Greek word konas, meaning “vertigo” or “whirl,” representing hemlock poisoning symptoms.

The compound that kills is coniine, which blocks the neuromuscular junction to cause suffocation. Survival requires a ventilator. According to legend, this innocuous-looking shrub—a member of the carrot family—only became toxic at Christ’s crucifixion, cursed via contact with his blood. Its appearance, however, was unchanged, and it’s often mistaken for lookalikes, such as wild carrot, parsley, and caraway.

The key to IDing is to crush and smell the leaves. If they smell like “mouse urine and off parsnips” (and you still feel like eating them), desist! Incidentally, the similar-smelling leaves of the hemlock tree, otherwise unrelated, are how it gets its name.

Another hemlock to watch out for is Conium maculatum, or hemlock water-dropwort. Common around streams, it has the carrot family leaves, an “acrid celery” smell, and bulbous, toxic roots known as dead man’s fingers. Uprooted by storms, it’s the latter that often kills dogs.

Both were used for execution — particularly in Sardinia. Its tightening effect on the muscles of the face, drawing them into a sinister grimace, is the origin of the phrase “sardonic (from Sardinian) smile.”

3. Yew

The yew tree has long been a symbol of death. The ancient Greeks associated it with Hades, the Furies, and Hecate, goddess of necromancy, witchcraft, and ghosts. For the ancient Druids, it symbolized immortality —which may be why it’s so common in English churchyards, many of which were built on pagan sites. An old legend has it that the tree imbibed gases (or will o’ the-wisps) from corpses underground to make poison.

As a symbol of everlasting life and numinous power, yew is the wood of choice for magic wands and royal staffs — like the rod of office in the Highlands. Ironically, though, even just handling it can be deadly… eventually. Medieval longbow-makers were allegedly poisoned this way.

Symptoms of yew poisoning include convulsions, difficulty breathing, and especially heart failure strong enough to kill a moose. When consumed, the poison takes effect so rapidly that animals so-killed are often found with the leaves half-chewed in their mouths. That it can wipe out whole herds may be another reason it’s common in graveyards: to keep it from hungry livestock (though usually, they know to avoid it).

So why do people still eat it? Yew berry tart is, says its maker, the plant-based equivalent of fugu. While the leaves, bark, wood, and seeds are toxic, the berries, surprisingly, are not. Actually, they’re pretty tasty—but they’re risky to use in the kitchen. Only the flesh or aril is edible; the seed inside has the highest concentration of the tree’s deadly taxine B.

(By the way, if you do ever find yourself feeling sick while grazing an English churchyard, atropine might take the edge off. Follow the yew with some deadly nightshade, and you might just feel well enough to dig your own grave.)

2. Wolf’s bane

Despite the name, wolf’s bane kills indiscriminately. It was supposedly used to poison arrows to kill wolves (hence the taxonomic name Aconitum, derived from the Greek word for “dart”). But the Anglo-Saxons just knew it as thung, like any other highly poisonous plant.

Eating wolf’s bane causes numbness in the mouth, nausea, vomiting, a weak pulse, difficulty breathing, and a sense of things crawling on the skin. The poison at work is aconitine. Made by Hecate from the hell-foam of Cerberus, it’s best kept out of the kitchen.

Even though easily mistaken for horseradish, it hardly needs the disguise. Asian communities wolf down the roots for their purported medical benefits. The president of Kyrgyzstan even recommended wolf’s bane as a cure for COVID-19—hospitalizing four of his voters.

Historically,  it was among the poisons most feared by the death-fearing Pope Clement VII. In 1524, he was approached by a surgeon with a general antidote to poison, which he tested with aconitine. After feeding two prisoners wolf’s bane-laced marzipan cakes, he gave one prisoner the remedy and it worked; the other he let die in agony. Deservedly, the paranoid pontiff was later killed off with death caps.

1. Death caps

Death cap mushrooms in Catalan oil was, said Voltaire, the dish that changed the future of Europe. In 1740, Emperor Charles IV—besieged by political intrigue, financial crisis, and (on this fateful day) the common cold—called for his comfort food of choice. Usually, it lacked the poison mushrooms, which had found their way in “accidentally.” He fell sick within hours and couldn’t be helped. The following month he was dead.

But the emperor was apparently special, since death caps tend to work faster. Symptoms like dizziness, chills, and nausea only appear once the liver is critically weakened, 8-12 hours after intake. By this point, it’s often too late. Although later symptoms like vomiting and diarrhea abate and people may start to feel better, the liver and kidneys both shut down within days. 

The toxin to blame is aminitin, of which there’s enough in half a cap to kill a human. Unfortunately, there’s also no known antidote. With its delayed but near-certain prognosis of death, it’s been used in assassinations for millennia. This was the fate of Emperor Claudius in 54 AD at the hands of his wife Agrippina, clearing the way for her son Nero to replace him.

There’s another reason it’s such a good weapon. According to many death cap victims, the mushroom itself is delicious. So not only would an emperor’s taster not die right away, they’d heartily recommend the dish.