50 of the Deadliest Plants and Animals on Earth

The world can be a dangerous place sometimes. Although humans don’t have any natural predators, there are still plenty of animals that can and will kill humans when given the chance. And for anyone that finds themselves lost in the wilderness, foraging for food, there are a lot of plants that can be far more deadly than any animal that person may stumble across. So today we’ll be looking at 50 of the plants and animals that are deadliest to humans.

White Baneberry

White baneberry is also sometimes referred to as doll’s eyes, because the white berries bare an uncanny resemblance to eyeballs. The plant is native to eastern North America, found in both Canada and the United States, and it can even be found as far inland as the American Midwest.

While many plants only contain toxins in either the berries, leaves, or stems, the entire baneberry plant is poisonous to humans. The berries and roots are the most toxic, as they contain an as of yet unidentified cardiogenic toxin. Ingestion of this toxin causes the immediate sedation of the heart, which can result in cardiac arrest and death. It only takes a few berries for a person to become seriously ill.

There is a similar plant, the red baneberry, which is equally poisonous to humans. Red baneberry is potentially even more dangerous, as the red berries are more appealing, whereas the doll’s eyes are a bit creepy and off putting.

Box Jellyfish

Box jellyfish are often referred to as the most venomous species of marine animal in the world, but they actually make up a class of about 50 different species. All box jellyfish are dangerous, though stings from some of these species will only result in multiple days of ceaseless pain rather than death.

The most venomous species live in the Indian and Pacific Oceans, and the deadliest species is the Australian box jellyfish of the northern coast of Australia. These jellyfish have 80 tentacles that can grow to up to 3 meters in length each, and each tentacle is covered in millions of tiny hooks that deliver a myriad of toxins when they come into contact with the jellyfish’s prey, or an unfortunate human.

Each Australian box jellyfish contains enough venom to kill 60 adults, and it acts extremely quickly, able to kill a person within minutes of the venom taking effect. While many people have been told that urinating on a jellyfish sting can relieve the pain, this is not true; it likely stems from the equally false belief that ammonia is effective at treating the stings. The only effective form of first aid is to douse the wound with vinegar for 30 seconds, and Australian beaches are stocked with bottles of vinegar if such a need arises.

In 2019, an antivenom was developed to combat the box jellyfish stings. Although it was shown to be effective in labs, in the real world the results have been mixed. While an antivenom can neutralize the venom and prevent it from causing any more harm to a person, any damage it’s already done cannot be reversed.

Because the venom attacks the heart and works extremely quickly, victims of the Australian box jellyfish may suffer fatal damage to their hearts before there is a chance to administer the antivenom.

Castor Bean

Castor beans have been an important crop for thousands of years. Believed to be native to eastern Africa, the castor oil plant now appears in many tropical and subtropical areas throughout the world, often as a weed.

What are often referred to as beans are actually seeds, and these seeds contain 40-60% oil. Use of this oil in medicine, cosmetics, and as fuel for lamps dates back to at least 4000 BC in Egypt and 2000 BC in India, the latter of which is now the world’s largest producer of castor beans. In modern times it is used in animal feed, as an antimicrobial agent, for biodiesel, in plastics, and more.

The oil is extracted from the seeds by pressing them, leaving only the pulp behind. But as anyone who watched Breaking Bad may remember, the pulp of the castor bean contains the deadly toxin ricin. As little as one milligram of ricin is enough to kill an adult, and there is no antidote available. Both the US and UK militaries claim to have created antidotes, but neither has undergone significant human testing.

Ricin works by preventing cells from producing new proteins. When ingested, this affects the gastrointestinal tract, causing symptoms similar to food poisoning. These symptoms increase in severity with internal bleeding and bloody bowel movements, resulting in dehydration and low blood pressure. If untreated, this can lead to organ failure of the kidney, liver, and pancreas, and the victim will die within 3-5 days.

Although there is no available antidote, treating the symptoms caused by ricin usually can prevent ingestion from being fatal.

Black Mamba

Africa is home to over 150 different venomous snakes, and there are over 20,000 reported deaths from snakebites in Africa each year. It’s believed that the number of actual deaths is over 30,000, but that many bite victims don’t seek medical attention and thus aren’t reported. Of all the snakes in Africa, however, there is none more feared than the black mamba.

The black mamba is regarded as the deadliest snake in Africa. Not only is it highly venomous, it’s big and aggressive as well. An average adult black mamba is over 2 meters long, often reaching 3 meters in length. Some have even been reported to be as long as 4.5 meters, all of which makes it the second longest venomous snake in the world, only losing out to the king cobra.

Though they are considered to be highly aggressive, black mambas only attack humans when they feel threatened or cornered. When this happens it will display the inside of its mouth, which is where its name comes from. The snakes themselves are either grey or brown, but the inside of their mouths are black.

Black mambas will often bite their prey multiple times, injecting more venom with each bite. The venom contains a fast acting neurotoxin, and victims will begin showing symptoms within 10 minutes of being bit. It can start with a sensation that their skin is tingling, blurred vision, and slurred speech. It quickly progresses to twitching muscles, loss of voluntary movement, and difficulty breathing.

Within 45 minutes of being bitten, a person will usually collapse. In just 7 to 15 hours from the initial bite, it results in respiratory failure and death. Black mamba bites have a near 100% mortality rate when left untreated, but an effective antivenom was developed in the 1950s and 60s. So long as a person receives treatment quickly, most are able to recover from a mamba bite.

Lily of the Valley

While ricin played a larger role in the plot, fans of Breaking Bad may remember another poisonous plant from the show, Lily of the Valley. It is native to Europe and Asia, though a subspecies, American Lily of the Valley, is native to North America.

The flower has also been popular in bridal bouquets and as an inspiration for perfumes. However, because the flowers have no aromatic extracts that can be used in perfumes, the scent of the flowers must instead be simulated.

Lily of the Valley produces bright red berries, which can look highly appealing to children and animals that don’t know better. Unfortunately, all parts of the plant are highly poisonous, containing 38 different toxins. The symptoms of ingesting Lily of the Valley are similar to the symptoms of ricin, though generally not as severe.

Fortunately, cases of people dying from ingesting Lily of the Valley are exceptionally rare. Plants produce different toxins as a defense mechanism to protect them from predators, but the Lily of the Valley has a second defense mechanism that is likely the reason fatalities caused by the plant are so rare: it tastes horrible.

Oh sure, the berries may taste sweet at first, but that sweetness quickly dissipates, instead being replaced by an intensely bitter taste. It’s likely because of the plant’s bitterness that people usually stop eating before consuming a lethal dose of poison.

Brown Recluse

Of the thousands of types of spiders that are native to North America, only about a dozen are considered medically relevant. And of those, the brown recluse is considered to be one of the two deadliest spiders, along with the black widow. Neither of these are actually that deadly to humans, but it only seemed fair to include one of the United States’ deadliest spiders.

As the name might suggest, the brown recluse is both brown and reclusive. They are so timid and reclusive that a house could be infested with thousands of brown recluses without the residents ever being bitten a single time, something that there is multiple documented cases of.

These spiders are usually only active at night, and they flee from humans whenever possible. The only time a person is likely to be bit by a recluse is when the spider is pressed against a person’s skin, like when putting on shoes or a shirt that a recluse has hidden inside. The spider would have to be trapped directly against the skin in order to bite though, as their fangs aren’t long enough to make it through most fabric. In the majority of cases, these bites are harmless and cause no symptoms.

But when there are symptoms, it can get pretty bad. About 37% of brown recluse bites will become painful and itchy in the hours immediately following the bite. Anywhere from 12 to 36 hours after the initial bite the pain will intensify as necrosis sets in. Over the next few days, the area of necrotic skin can spread until it reaches 25 cm (10 inches) in diameter. Eventually it will heal, but it leaves large, deep scars.

In 14% of cases, the venom results in systemic illness rather than just localized necrosis. Though severe, these cases are still rarely fatal except in the case of young children, the elderly, or those with compromised immune systems.

Hemlock

Hemlock has long been known to be one of the most deadly plants in the world to humans. It’s native to Europe and northern Africa, though it has spread all across the world, often as an invasive weed.

One of the most famous cases of hemlock poisoning was that of Socrates in 399 BC. Socrates was tried and found guilty of heresy and corrupting the young minds of Athens. As was customary in ancient Athens, Socrates was given the opportunity to propose his own penalty. He proposed that he be given free food and housing by the government as payment for his services to the city. The jurors respectfully declined this punishment and instead sentenced him to death by drinking poison hemlock.

It takes six or eight fresh leaves to kill an adult human, though the seeds and roots are far more potent. The key chemical in the toxicity of hemlock is coniine. The initial effects appear similar to those of narcotics, and within 30 minutes of ingesting hemlock a person will fall into a deep sleep. A few hours later they will be dead of asphyxiation caused by failure of the respiratory muscles.

There is no known cure for hemlock poisoning, and the only treatment is to put somebody on a ventilator until the poison leaves their system and the symptoms subside.

Mosquitoes

Mosquitoes are horrible, vile creatures that the world would be better off without. Most ecologists would disagree with the last part of that statement, as mosquitoes pollinate plants and act as a food source for a number of other animals. Still, most people find mosquitoes to be annoying pests that are the cause of a lot of itchy discomfort.

But while most of us tend to just think of mosquitoes as pests, they are much more than that. Of all of the animals in the world, mosquitoes are the number one killer of humans. Conservative estimates put the number of human deaths caused by mosquitoes at 1 million per year, while other estimates believe it is 2 or 3 million each year.

Obviously mosquitoes aren’t directly killing humans, literally sucking them dry of every drop of blood in their bodies. Instead, mosquitoes kill by acting as disease vectors. The number one disease mosquitoes transmit to humans that results in death is malaria, but it’s hardly the only one. Dengue, Zika, West Nile virus, yellow fever, and chikungunya are all potentially fatal viruses spread by the bites of mosquitoes.

Even if they don’t kill humans directly through the use of venom, mosquito bites remain the most common killer of humans in the animal world. And with anywhere from 100 trillion to 1 quadrillion mosquitoes in the world, it’s not like we can just easily avoid them.

Rosary Pea

Abrus precatorius, better known as the jequirity bean or rosary pea, is a plant native to Asia and Australia. However, it is capable of growing anywhere with a temperate or tropical climate, so the plants are now found all over the world. It was deliberately spread by humans, but the plants are extremely invasive and difficult to remove. Because the plants are so aggressive and resilient, most eradication attempts fail and the area is quickly reinfested.

The most notable part of the plant, and the one from which its name derives, are the seeds. These seeds are typically red with a black spot on the end, somewhat resembling a ladybug. They also have extremely hard shells, which made them great for use in jewelry. Their use as prayer necklaces is how they became known as rosary peas.

Because the seeds tend to be uniform in size, another feature that makes them great for jewelry making, they were even used in ancient times across the Indian subcontinent as a unit of measurement for weight. The hard shells are impermeable to water, so moisture would not impact their use as a standard unit of measurement.

Unfortunately, despite their uses, rosary peas contain a toxin known as abrin. The effects of abrin are the same as ricin, except it is much deadlier. Whereas it would take three castor beans to provide a lethal dose of ricin for a child and up to eight castor beans to kill an adult, a single rosary pea is enough to kill any human.

African Elephant

The African Elephant is the largest and strongest land mammal in the world. They can be up to 4 meters tall, nearly as long, and weigh over 5,400 kg. Not only are they enormous, elephants are strong enough to push over full grown trees with minimal effort. Despite this incredible strength, African elephants are generally peaceful creatures.

And why wouldn’t they be? They’re herbivores so they have no need to kill other animals for meat, and they have no natural predators because they’re simply too big for other animals to attack. Sometimes predatory animals like lions or crocodiles may attack a baby elephant, but by the time they reach adulthood there aren’t really any non-human predators that would risk going head to head with such a gargantuan creature.

However, when elephants feel threatened, provoked, or when something is standing between them and their next meal, they will attack. For a long time this has resulted in elephants and humans coming into conflict, as the loss of their natural habitat has forced elephants into smaller areas with not enough food.

Attacks from African elephants are most common when, unable to find food in the areas humans have pushed them to, they raid local farms to eat their crops. Roughly 500 people are killed each year by African elephants, and attacks on humans from all types of elephants have been increasing as the effects of climate change damage their ecosystem, making food and water harder to find.

White Snakeroot

There are no known documented cases of humans ever eating white snakeroot, yet the plant has been responsible for thousands of deaths. White snakeroot is a member of the daisy family that is native to eastern and central North America. When European settlers moved to North America they were unfamiliar with the plant and its toxic properties, but they also didn’t consider it food.

However, it was seen as perfectly acceptable for livestock to graze on. Snakeroot contains the toxic compound tremetol, and consuming meat and milk from cows that grazed on the plant would pass the toxins on to humans. This earned the condition the name milk sickness, as settlers were able to identify that the illness was caused by milk, even if they couldn’t figure out what was causing the milk to become tainted.

The main symptom in livestock was trembling, and in humans it would cause trembling, vomiting, severe intestinal pain, and eventually death. It was so deadly that milk sickness would sometimes kill half the population of a frontier settlement, and it’s even believed that Abraham Lincoln’s mother died from milk sickness.

Although farmers were able to solve the problem by cultivating fields specifically for cattle to graze on, white snakeroot wasn’t identified as the toxic plant behind milk sickness until 1928.

Crocodiles

People in the United States are far more familiar with alligators than crocodiles, thanks to the over 1 million alligators that call Florida their home. They are well known to be dangerous, however fatal attacks from alligators, especially unprovoked ones, are extremely rare. Alligators will usually only attack humans if they feel threatened, and most attacks aren’t fatal.

The same cannot be said for their oversized cousins, the crocodile. There are 26 extant species of crocodiles around the world, and together they are responsible for over 1,000 human deaths each year. The two deadliest species are the Nile Crocodile, native to Africa, and the Saltwater Crocodile, native to India, Southeast Asia, Micronesia, and Australia. These are the two species that are most likely to see humans as prey, and over 50% of attacks from Nile and saltwater crocodiles are fatal.

Both species of crocodile can grow to be 6 meters in length, and saltwater crocodiles can weigh up to 1,500 kg, making them the largest living reptiles. Despite their massive size, they can reach speeds of up to 18 mph in the water. These crocodiles are also extremely aggressive and territorial, so any person walking into a Nile or saltwater crocodile’s territory may quickly find themselves becoming its prey.

Unfortunately, you can’t avoid saltwater crocodiles simply by avoiding saltwater. Despite their name, they can also be found in brackish waters and freshwater swamps, rather than just salt water.

Water Hemlock

Native to both North America and Europe, this cousin of hemlock is considered one of the most poisonous plants in North America. That said, water hemlock is actually the colloquial name for the genus Cicuta, which is comprised of four different species of plants. All four are extremely toxic and deadly to humans, thanks to the compound cicutoxin.

This poison is a type of alcohol that acts as a neurotoxin, causing hyperactivity in the brain that results in seizures. Symptoms can begin to manifest in just 15 minutes after coming into contact with water hemlock, with seizures often being the first noticeable symptom. Other symptoms include nausea, vomiting, abdominal pain, confusion, drowsiness, and more. Death can occur in just a few hours, usually caused by either respiratory failure or ventricular fibrillation, resulting from wild, repeated swings between low and high blood pressure.

Exactly how much water hemlock is considered a lethal dose is unknown, but it’s very little. There are reported instances in which children used the hollow stem of water hemlock as a whistle, an act that often proved fatal. There are even cases where people have died simply from their skin coming into contact with the plant rather than actually by ingesting it.

Hippopotamus

Most people think of hippos as being docile, friendly creatures. But that’s just what they want you to think. Whether it’s in cartoons, children’s books, or the board game Hungry Hungry Hippos, these creatures are generally depicted as being cute, chubby, and lethargic. Fortunately, people are finally coming around to the fact that this is all just a tactical propaganda campaign put forth by big hippo to lull humans into a false sense of security.

In reality, hippos are considered the deadliest land mammal in the world to humans, accounting for over 500 human deaths every year. Just like crocodiles, they are extremely aggressive and territorial, arguably even more so.

If the need arises to traverse crocodile infested waters, boats usually provide adequate protection, as the crocodiles are unlikely to attack a boat. But hippos do not screw around, and they absolutely can and will capsize any boats that wander into their territory. This often results in deaths, either by drowning or by being attacked by the hippo directly after they are thrown from the boat.

Hippos weigh an average of 1500 kg, more than enough to crush a human, and they have incredibly sharp teeth as well. They’re also fast, able to sprint at speeds of up to 19 mph. And unlike other amphibious creatures, hippos are faster on land than in the water because they can’t actually swim.

They are far too dense to float, so even when submerged in a river they move by walking along the ground. This all means that there is little to no escape from an enraged hippo, as they are twice as fast as humans both in the water and on land. Your best bet is to run in a zigzag pattern, as hippos are unable to turn quickly.

Deadly Nightshade

Atropa bella-donna, more commonly known as deadly nightshade, has a long history of use by humans. It was often used in various herbal remedies as well as being used in cosmetics. Its cosmetic use is where it got the name bella-donna, or “beautiful woman” in Italian. Eye drops would be made from the juice of the nightshade berries which were used to dilate the pupils, something that was seen as making a woman appear more seductive back in the day.

However, despite its extensive use, deadly nightshade is extremely deadly, as the name might suggest. It contains tropane alkaloids which disrupt the nervous system causing dilated pupils, blurred vision, loss of balance, delirium, confusion, hallucinations, convulsions, and eventually death.

All parts of the nightshade plant are toxic to humans, with the roots being the deadliest. Still, a single berry can be fatal for a child, and 10 berries or one leaf are typically fatal for adults. It’s so toxic that even honey produced by bees that drink nectar from nightshade plants can be fatal, similar to the “mad honey” from bees drinking nectar from certain hallucinogenic plants.

Because nightshade is from the same family of plants as tomatoes and has a similar taste, people have consumed lethal doses of nightshade by mistaking them for other berries. It can even still be found in some dietary supplements and medicines, even though there is no scientific evidence supporting its use as medicine.

Deadly nightshade has also seen some amount of use as a recreational drug because of its hallucinogenic effects, however this never gained widespread popularity because of the high risk of fatality and the fact that the hallucinations caused by nightshade are described as being horrifying rather than fun.

Death Adder

There are several species of death adder around the world, but one of the most venomous is the common death adder. Native to Australia, the common death adder’s venom contains a highly potent neurotoxin that disables its prey.

Once the venom is injected, it begins with pain and swelling at the site of the wound, followed by blurred vision and respiratory distress. This progresses to paralysis and respiratory failure, with about 60% of bites being fatal to humans when left untreated.

That 60% mortality rate isn’t because some people survived the venom though, it’s because the death adder only injects its venom in about 60% of bites. When venom is injected, each dose is enough to kill several adult humans.

Fortunately, despite being one of the most venomous snakes in the world, human deaths from the common death adder are increasingly rare. A big part of this is thanks to the development of antivenom that treats bites from the death adder, but even before then deaths were uncommon.

This is because death adders are ambush predators. While many other species of snakes go out actively hunting for prey, the death adder just sits and waits, often burying itself under leaves to further camouflage itself from its prey. Once something gets close enough, the adder will strike with blistering speed, faster than the human eye can properly register.

Manchineel

The manchineel tree is native to tropical areas of North and South America. Its name comes from the Spanish “manzanilla”, or “little apple”, as the fruit and leaves of the tree resemble that of an apple tree. But it quickly became known as “manzanilla de la muerte”, or the “little apple of death” because it is one of the most toxic trees in the world.

In fact, the tree is so toxic that there aren’t any records of people dying from eating it anywhere in modern literature. That may sound counterintuitive, but perhaps nowhere else in the world is there a plant so overtly dangerous that people wouldn’t dare eat it.

The tree contains a milky white sap that permeates every part of the tree, including the bark, leaves, and fruit. This sap contains numerous different toxins, many of which are skin irritants that cause an immediate reaction upon contact. Hiding under the tree for shelter in the rain is enough to cause an adverse reaction, as raindrops can pick up sap from the leaves, causing the skin to immediately blister as they land on the person beneath the tree. The same is even true of dew drops falling from the tree.

Explorers from the 1600s and 1700s discovered the dangers of the manchineel upon their first encounters with it. One explorer cut off a branch to fan mosquitoes away from his face, only for his face to swell to such a degree that he was blind for several days.

In a 2000 paper written by someone who unknowingly took a small bite of one of the apples, the taste was described as “pleasantly sweet”. That sweetness quickly morphed into a “burning, tearing sensation and tightness of the throat”. The pain eventually became so much that he could barely swallow food from the swelling.

Ingestion can also cause swelling and bleeding of the stomach, shock, infections, or suffocation from the throat swelling shut. But since merely touching the tree is enough to cause the skin to blister, nobody can say the tree didn’t warn you.

Cone Snail

Cone snails get their name from the large, conical shaped shells they inhabit. There are over 900 species of cone snails inhabiting warm, tropical seas and oceans around the world. Their shells are prized among shell collectors and jewelry makers, as they come in a variety of colours and patterns.

However, these snails are also venomous carnivores that can extend a large, harpoon-like tooth out from their head to envenomate prey. This makes collecting these shells dangerous, as shooting their harpoons is the snail’s instinctive response to its shell being disturbed.

For smaller snails that hunt worms, this isn’t too dangerous for people. The stings will be painful, but not life threatening. But stings from the larger cone snails that hunt fish can be fatal, and the harpoons are strong enough to pierce through a glove or wetsuit to strike the victim.

Symptoms of the cone snail venom begin with severe pain, swelling, numbness, and tingling at the site of the injection. Later symptoms include muscle paralysis, changes in vision, and respiratory failure. The symptoms of the venom can manifest immediately, though sometimes it may take days to do so.

One of the more dangerous species of cone snails to humans, the geography cone, is also nicknamed the “cigarette snail”. It was called this because people claimed that once a person was stung by a geography cone, they would only have enough time to smoke a cigarette before they died. While that’s an exaggeration of how quickly the venom kills someone, it does still highlight how deadly these snails can be.

Suicide Tree

Native to South and Southeast Asia, the Pacific Islands, and Australia, the tree Cerbera odollam is better known as the suicide tree. And unlike our last tree that was too toxic to kill anyone, the suicide tree is responsible for deaths on a regular basis.

The tree produces a poisonous fruit, but far more deadly are the seeds. Each fruit contains a kernel with two seeds, and one kernel has enough poison to kill an adult. The poison found within the seeds is called cerberin, a cardiac glycoside that can cause the person to die from their heart pumping too much, not enough, or not at all.

Although the fruit is also poisonous, it contains a lower dose of cerberin. Eating the fruit usually only results in symptoms similar to that of severe food poisoning, but that’s enough to keep people from eating the fruit. It’s the seeds that people eat, whether willingly or unknowingly.

The seeds of the suicide tree have a somewhat bitter taste, but it’s also extremely mild. The taste is easily masked by spices, which has made it popular as a means by which to commit suicide, as evidenced by the tree’s name. And because the taste of the seeds is so easy to mask, it’s also a favourite of people wanting to kill via poison. Death usually occurs in just 3-6 hours after consuming the seeds.

While it’s difficult to find exact worldwide numbers, it is estimated that hundreds of people in India alone die each year from eating the seeds of the suicide tree.

Blue-Ringed Octopus

There are four species of blue-ringed octopus in the Pacific Ocean stretching from Japan to Australia. As the name might suggest, they can be easily identified by the bright blue rings that cover their bodies.

These octopuses are generally considered docile and are small enough to fit in your hand, but absolutely do not try to pick one up. If they feel threatened or provoked they will attack, and their bites are extremely deadly.

Blue-ringed octopuses use the powerful neurotoxin tetrodoxin. This is the same poison found in the Fugu fish and some other aquatic animals, though the octopuses are the only known animals to use tetrodoxin as a venom to attack their prey rather than as poison to dissuade predators.

Each octopus contains enough tetrodoxin to kill 26 adult humans, and a single bite can be lethal. Even worse, their bites are often painless, meaning that a human who is bit by a blue-ringed octopus may have no idea it even happened until they’re already paralyzed and struggling to breathe.

This is especially bad because there is no antivenom for the toxin. The only treatment is to put a victim on a ventilator to help them breathe while their respiratory muscles are paralyzed. Because a victim only has minutes between being bitten and death, any delay in seeking emergency medical attention might be fatal.

Angel’s Trumpets

The genus Brugmansia, part of the nightshade family, contains seven species of plants that are commonly referred to as angel’s trumpets. They’re closely related to another genus, Datura, that are referred to as devil’s trumpets. Angel’s trumpets have large, downward facing flowers as if they were trumpets being played from the heavens, whereas devil’s trumpets have large, upward facing flowers as if they were trumpets being played from Hell.

All parts of the plant are potentially poisonous, though the seeds and leaves are the most toxic. Similar to deadly nightshade, angel’s trumpets contain several tropane alkaloids. Ingestion can result in paralysis, confusion, tremors, migraines, hallucinations, and death, among other symptoms.

Angel’s trumpets have seen significantly more use as a recreational drug than nightshade, even though the hallucinations are described as being equally unpleasant. The hallucinations from angel’s trumpets often result in psychosis and amnesia, and there is a documented account of a man cutting off his own tongue and penis after drinking a single cup of tea made from the plant’s leaves.

Golden Poison Frog

In nature, the more brightly coloured an animal is, the more likely it is that you want to stay away from it. The bright colours are meant as a warning, and the golden poison frog is warning you that it is one of the most poisonous animals on the entire planet.

These frogs are the largest species of the poison dart frog family, and they are by far the most deadly. The skin of the golden poison frog produces batrachotoxin, an extremely rare and lethal poison produced only by three frogs in Columbia and a few birds and beetles in Papua New Guinea.

Although the poison is classified as a neurotoxin, it has significant cardiac effects as well. Exposure to the toxin causes nerve cells to leave a person’s muscles permanently contracted, resulting in paralysis, but the cause of death is heart fibrillation and heart failure.

Lethal doses of various toxins found in plants and animals are usually measured in either grams or milligrams, but batrachotoxin is so deadly that the lethal dose for a human is only a few micrograms. Each adult frog is only about 6 cm long and only weighs 30 grams, yet it has enough poison in its body to kill 10 or 20 adult humans, or 2 African elephants. In fact, the frogs are so toxic that it’s believed they have no natural predators, as no animal would dare try to eat one.

Golden poison frogs were long used by indigenous people as a source of poison for the darts they used to hunt game, but the frogs are now endangered due to destruction of their rainforest habitat.

Devil’s Trumpets

It’s not just the direction of the flowers that give devil’s trumpets their name. Well, it probably is, but devil’s trumpets have a long history of far more sinister uses than angel’s trumpets. Though they have many of the same effects as angel’s trumpets, devil’s trumpets are a much more powerful deliriant.

Not only does ingestion of these flowers cause hallucinations, it can also cause hyperactivity. This causes the people who consume it to become highly confused and agitated, usually resulting in them needing to be hospitalized.

Of course, not everyone who ingests devil’s trumpets has the opportunity to be hospitalized. Because devil’s trumpets have a higher concentration of toxins than angel’s trumpets, they have been a popular form of poison both for suicide and murder for centuries. A study out of India from 1950 through 1965 revealed nearly 3,000 deaths from devil’s trumpets in India alone, many of which were murders carried out by a religious cult.

While angel’s trumpets are common in gardens around the world, many countries have placed regulations on the sale and cultivation of devil’s trumpets because of its more potent toxins.

Tsetse Fly

Tsetse flies share a lot in common with mosquitoes. These are small, bloodsucking insects, roughly the size of a house fly, that act as disease vectors. While the insect bites themselves are harmless but annoying to humans, tsetse flies infect their victims with a parasite known as trypanosomes.

These single celled parasites cause African typanosomiasis, also known as African sleeping sickness. There are two different strains of this parasite, one of which is more acute and fast acting, but the symptoms are the same in each case.

The first stage begins with a bunch of nondescript symptoms such as fever, headaches, and joint pain. In the second stage, neurological symptoms develop. These include confusion, numbness, loss of coordination, and trouble sleeping. As the disease progresses the patient experiences severe mental deterioration, often accompanied by delirium, hallucinations, and psychosis. Eventually the victim will fall in a coma and die from systemic organ failure.

African sleeping disease is nearly 100% fatal if left untreated. Fortunately, treatment for the infection has improved. In the 1900s tsetse flies were responsible for tens or even hundreds of thousands of deaths each year, but that number is now down to about 3,500.

Monkshood

Monkshood, also known as wolfsbane (and about 20 other names) is a genus of 250 species of plants, all highly poisonous. The entire plant, particularly the roots, is filled with a toxin called aconitine. As little as 2 mg of aconitine can be fatal, and a person would only need to consume 1 gram of monkshood to ingest that amount of poison.

Aconitine is a powerful neurotoxin and cardiotoxin, and symptoms appear almost immediately after ingesting the poison. It begins with typical gastrointestinal unpleasantness, followed by burning and tingling sensations that begin in the mouth and abdomen and may spread throughout the body. Within 1 to 6 hours, the person will usually have died either from respiratory failure, arrhythmia, or paralysis of the heart.

But that’s just for a small dose of the poison. In cases where a person ingested a large dose, death is immediate.

Despite its incredibly toxic nature, monkshood is highly sought after by gardeners and florists because of the tall, violet flowers the plant produces. They’re so in demand that people are actively cultivating new hybrid species of monkshood, some of them even winning awards. As much as the beautiful flowers are prized by gardeners, however, special care must be taken when handling them as even touching the plants can result in severe toxicity.

Ascaris Roundworms

The Ascaris roundworm is the most common parasitic worm found in humans. They can be found all over the world in tropical and subtropical climates, though infections are most common in developing nations.

Eggs are often transmitted from one person to another via human feces. This is a major problem in areas with poor hygiene and sanitation, and especially places where raw human feces are used as fertilizer for crops. Roundworm eggs that find their way into the soil this way can remain viable for up to 10 years.

Once swallowed, eggs will hatch into larva in the small intestine. The larvae will then break out of the intestine and into the bloodstream, breaking out again once they reach the lungs. It’s quite a long journey, and a seemingly pointless one at that. The larvae cause inflammation in the lungs, resulting in them being coughed up into the throat and swallowed again, returning to the intestines where they stay and mature into adult worms.

There are a few different ways that these parasites can kill a human, but the most common is intestinal blockage, especially in children. Female roundworms can lay 200,000 eggs per day, and if enough worms accumulate they may create a tangled ball that blocks any movement through the intestines. Even when not fatal, children may suffer from malnutrition and learning disabilities resulting from one of these infections.

Estimates for how many people die each year from ascaris roundworms vary wildly. The most conservative numbers put it at about 2,700 people per year, though one 2014 study estimated that 60,000 people die each year from these infections. But perhaps more concerning than the number of deaths is the number of people infected with these worms, as it’s estimated that between 800 million and 1.2 billion people are currently host to ascaris roundworms.

Infections can be treated with a number of different oral, anti-parasitic medications, but the vast majority of cases are in poorer countries that lack easy access to these medications.

Strychnine Tree

You’ve undoubtedly heard of the deadly poison strychnine before, but far less publicized than the poison itself is the fact that strychnine actually grows on the strychnine tree. These trees are native to India and Southeast Asia, and they have had no real use since their discovery other than being a deadly poison.

Strychnine is sometimes used in herbal medicine, but there is zero evidence that it is helpful in any way. Its more common use throughout history has been as an arrow poison for hunting and warfare.

The poison strychnine is found in the seeds and blossoms of the tree, though other parts of the tree contain other toxins as well. Each seed is made of approximately 1.5% strychnine, which is roughly 0.25-0.5 mg of poison per seed. The lethal dose for humans ranges from 30-120 mg depending on weight so ingesting a single seed is unlikely to be fatal, but even a nonlethal dose of strychnine has serious effects.

Probably the most well known symptom of strychnine poisoning, other than death, are the violent muscle spasms it causes. It also results in seizures, hyperthermia, organ failure, hypertension, and tachycardia, among many others. Death can occur in a number of ways, such as respiratory failure, cardiac arrest, multiple organ failure, or brain death.

While unpleasant symptoms like spasms can last for up to 24 hours after ingesting the poison, if the dose of strychnine is high enough to be lethal then the person will usually be dead in only 15-30 minutes.

Indian Red Scorpion

There’s a lot of debate over what is the deadliest scorpion in the world. The Deathstalker is thought to have the most potent and deadly mix of neurotoxins, but it envenomates its prey with far less poison than some other species, so the human mortality rate is only about 1-3%, and a healthy adult is unlikely to die from a Deathstalker’s sting.

Far more deadly to humans is the Indian Red Scorpion, which has a mortality rate of 8-40%, with children and the elderly being the most likely to die from its poison. As the name might suggest, the scorpions are most commonly found in India, though they are spread across much of South Asia.

The scorpion’s venom contains a mix of neurotoxins and cardiotoxins. Immediate symptoms of a sting include severe localized pain, sweating, and vomiting. Although, depending on how blessed the individual that was stung was, the most noticeable symptom may be priapism.

This is followed by convulsions, breathlessness, and abnormal heart rates and blood pressure. This leads to pulmonary edema, which is the usual cause of death from these stings.

No known scorpion antivenom has shown a meaningful effect at reducing the mortality rate from the Indian Red Scorpion, however treating the patient with medication for high blood pressure has been shown to reduce the mortality rate to less than 4%.

Rhubarb

There are a lot of things that might come to mind when you think of rhubarb. There’s rhubarb pie, rhubarb jam, rhubarb preserves, and the 1951 comedy movie Rhubarb about a cat that owned a baseball team. What probably doesn’t come to mind is poison.

And yet the leaves of rhubarb are highly toxic to humans, and we’re not fully sure why. It is known that rhubarb leaves contain oxalic acid, a substance that damages the kidneys. In smaller doses this results in kidney stones, while in larger doses it can cause kidney failure and death.

However, the toxic dose of oxalic acid is 15-30 grams, which would either require eating multiple kilograms of rhubarb leaves in one sitting or long term consumption of rhubarb leaves. It is believed there is another toxin in the leaves that may be responsible for the deaths attributed to rhubarb poisoning, but that toxin has yet to be identified.

This fortunately doesn’t come up often as rhubarb is typically sold without the leaves still attached. Rhubarb poisoning is most associated with World War I, when rhubarb leaves were mistakenly recommended as a food source in Britain.

Assassin Bugs

Assassin bugs make up a family of thousands of different insects. Most of these are harmless, even if their bites are exceptionally painful. However, it is a small group of assassin bugs that are also known as kissing bugs that are the most dangerous. They are referred to as kissing bugs because they bite people on the face, usually near the lips. Kissing bugs are most commonly found in tropical regions of Central and South America.

Considering we’ve already discussed mosquitoes and tsetse flies, you probably think you know where this is going. The assassin bugs bite someone, and they inject some deadly virus or parasite into the person. It’s certainly a reasonable guess, but assassin bugs don’t directly inject anything deadly into a person with their bites. Instead, the bugs bite a person, then poop on their face.

The feces of the assassin bugs contain a parasite that causes Chagas disease, and when a person scratches the bug bite or touches their face then mouth, they can introduce the parasites into their system.

Chagas disease is a chronic illness infecting over 6 million people and responsible for nearly 10,000 deaths each year. Although most cases are asymptomatic, Chagas can cause nerve damage, heart disease, and eventually heart failure.

The disease can be treated with antiparasitic drugs, especially if it is caught early. Unfortunately, many people who contract Chagas can’t afford medication, and an even larger amount don’t even realize they were infected, as the more severe symptoms may not present until 10 years or longer after the initial bug bite.

Gympie-Gympie

Dendrocnide moroides, also known as the stinging bush, stinging tree, or gympie-gympie is not directly deadly to humans. However, there are many rumours, claims, and anecdotes about people who were driven to suicide by the plant’s painful sting. Of all the alleged stories there is only one confirmed case of a person ending their life over the plant, but it is certainly something you would want to stay as far away from as possible.

Gympie-Gympie is native to the rainforest areas of Australia and the South Pacific. Although it is a fruit bearing plant, it is also venomous, with both the leaves and fruit being covered in tiny, toxic stingers. It is believed to be the most venomous plant in the entire world, even if that venom doesn’t directly cause death.

What it does cause, however, is severe, unbearable pain. When skin comes into contact with the needles, there is an immediate burning sensation. One botanist who was stung by the plant described it as “like being burned by hot acid and electrocuted at the same time”. The pain only intensifies over the next 20-30 minutes, and it will last for days. If you’re lucky, that is.

The needles are too small to be effectively removed with tweezers, so the standard treatment is to remove them with hot wax, the same way you would remove hair. However, because the needles are so small, often times the skin will close over them. When this happens, they will remain in the body and continue to release toxins, resulting in years of pain. Eventually it does finally stop when the toxins run out, so all you have to do is endure two years of something described as being ten times worse than the worst physical pain you could possibly imagine.

Saw-Scaled Viper

The Saw-Scaled Viper can be found in Northern Africa, the Middle East, and South Asia. They are very common, including in densely populated areas. While they are not the most toxic snake, with a mortality rate of about 20%, their frequent encounters with humans make them one of the most deadly snakes in the world, causing an estimated 5,000 deaths each year.

Saw-Scaled Vipers can be difficult to spot because they blend in with the dry, desert landscape. This can result in people unknowingly getting too close to one, which is a big problem. While many of the animals we’ve discussed today are only dangerous when threatened or provoked, these snakes are just looking for a fight. They are extremely aggressive, and if a person is close enough they will strike with little to no provocation.

The venom of the Saw-Scaled Viper contains a number of different toxins, but the most notable as it relates to human deaths are the hemotoxins. These toxins prevent blood from being able to clot, which can result in internal bleeding and kidney failure. Victims of the snake bites may also wind up bleeding out of every orifice in their body, with blood present in all of their bodily fluids.

Antivenom is effective at treating these bites, but left untreated a person who receives a lethal dose of venom can die in as little as 6 hours, though sometimes it takes a full day.

Rhododendron

Rhododendron is a genus comprising over 1,000 different species of plants. Most are native to Eastern Asia and the Himalayan area, though some are native to Europe, North America, Australia, and the rest of Asia.

Several species of rhododendron contain a toxin in their nectar and pollen known as grayanotoxin. This is often fatal to pets, though deaths from consuming rhododendron are rare among humans. Instead, the neurotoxins produce effects similar to that of a hallucinogen. Other symptoms include blurred vision, dizziness, confusion, general weakness, and nausea.

While deaths directly caused by ingesting rhododendron are extremely rare among humans, these plants have still been the cause of many human deaths thanks to their use as an early form of chemical warfare.

We briefly mentioned “mad honey” earlier, and it is bees that drank nectar from rhododendron that cultivated this honey. Because of its slightly hallucinogenic effects, this honey was weaponized in ancient Greece and Rome, with batches of mad honey being left behind for enemy soldiers.

Once they had become intoxicated by the mad honey, soldiers could come in and completely rout their victims.

Freshwater Snails

Freshwater snails can be found all over the world, and unlike the cone snails we discussed earlier they certainly seem harmless. However, for those living in tropical or subtropical climates, the mere presence of these snails is enough to kill a person, even if they never directly interact with the snails.

Freshwater snails are often host to parasitic flatworms called schistosomes. Snails release the flatworm larvae into the water where they can then infect humans, causing a disease known as schistosomiasis, or snail fever.

Women and children are the most likely to contract these parasites, as children will often play in tainted water and women will do water related chores like washing clothes. This is most common in poor and developing countries where there isn’t as much access to clean water, and over 230 million people worldwide are infected with schistosomiasis.

Many people don’t experience any symptoms of the infection, but when they do the symptoms can be severe and deadly. The flatworms will travel all over the body, and a lot of how severe an infection is depends on where they wind up. In cases where the parasites enter the spinal cord or brain, it can result in seizures, paralysis, and nerve damage.

More common is for the parasites to become lodged inside the kidney or liver, causing scarring and eventually leading to organ failure. Though the overall mortality rate is low, the organ damage caused by snail fever can make a person more susceptible to other diseases or infection. And even with a low mortality rate, it is estimated that freshwater snails are responsible for anywhere between 10,000 and 200,000 deaths each year.

Azalea

Azaleas are a special subgenus of rhododendron. They typically are less dangerous to humans than other rhododendron, however the mad honey produced from azaleas actually has a higher concentration of grayanotoxin.

This is being deliberately produced in parts of Turkey, where it is used as both a recreational drug and as a form of traditional medicine. However, because of the higher concentration of poison, mad honey produced from azaleas can be fatal on its own without the need for an opposing military force to finish the job.

In addition to the hallucinogenic effects of the neurotoxin, it can also cause spasms, tremors, and agitation. More severely, it can result in tachycardia and bradycardia, causing death by cardiac arrest. Because of the disruptions to muscle function, it can also cause death by respiratory failure as the respiratory muscles stop functioning properly.

Domesticated Dogs

When you think of deadly animals, domesticated dogs probably weren’t at the top of your list. Dogs can be used to help people hunt, track down criminals, and identify bombs or other contraband at airports. But sometimes, they also like to attack people.

In the United States, an average of 43 people each year die from being mauled by dogs, and the dogs in question are usually domesticated pets rather than feral dogs. But that’s not even the biggest danger when it comes to these animals. Dogs are the number one disease vector of rabies, accounting for 99% of all cases of rabies in humans.

For anyone unaware, rabies is absolutely terrifying. Although it usually lays dormant for 2-3 months after a person has been bitten, as soon as the first symptoms present it has a near 100% mortality rate. There are only a handful of documented cases of any human surviving symptomatic rabies.

There is a rabies vaccine that can be given after a person has been bitten before symptoms manifest that prevents any of this, and as a result cases of human rabies in the US and Europe are extremely rare, with only about 10 cases in the US each year. But in less developed nations in Africa and Asia, where they don’t have the same access to medical care, this is a much bigger problem.

According to the World Health Organization, nearly 60,000 people die each year from rabies, and almost all of those infections were caused by bites from man’s best friend.

Death Cap Mushrooms

If there’s one thing that everybody knows about mushrooms, or at the very least should know, it’s not to eat any wild mushrooms you find. Unless you really know what you’re doing, this can be absolutely disastrous. There are a lot of poisonous mushrooms out there, and many of them look dangerously similar to perfectly edible varieties.

And it is that last feature that makes the death cap mushroom so deadly. That, and all the deadly toxins inside it. Death caps look very similar to both the paddy straw mushroom and the white Caesar mushroom, two species of mushrooms that are popular and safe to eat. This results in death caps being misidentified and presumed safe to eat.

To make matters worse, death caps are described as tasting pleasant, and it takes 6 to 12 hours for symptoms to present. As a result, people may consume larger quantities of the mushrooms, believing them to be safe. But they are absolutely not.

On average, it takes just 30 grams of death cap to kill an adult. Early symptoms are your standard nausea, vomiting, and diarrhea, and these usually clear up after about 24 hours. This will often lead someone to believe that it was run of the mill food poisoning, preventing them from seeking medical treatment while their liver and kidneys are being destroyed by toxins.

About 72 hours after the original symptoms pass, the more serious symptoms of liver and kidney failure manifest. This includes jaundice, seizures, and coma, ultimately ending in death. In total it takes from 6 to 16 days for a person to die after eating death cap mushrooms.

Up until the mid-1900s the mortality rate for these mushrooms was over 60%, but thanks to advancements in medical treatments the mortality rate has fallen to only 10-30%. Still, multiple people die every year by mistaking death cap mushrooms for one of the safe, commonly consumed varieties.

Inland Taipan

Australia’s inland taipan can be found in the semi-arid regions near the border of Queensland and South Australia, but it’s best not to go looking for it as it is the most venomous snake in the world. The only reason it isn’t usually in the discussion for deadliest snake in the world is because humans rarely come into contact with them.

The location where the inland taipan lives is remote, so most people would never encounter them. These snakes also spend the majority of their days underground, living in burrows created by other animals. Unless a person is doing something to create excessive noise and vibrations, it’s unlikely that an inland taipan would react in any way to a human walking by.

Should a person be bitten, however, the result is almost always disastrous. The snake’s venom contains a cocktail of different poisons, one of which is believed to be the single most potent beta-neurotoxin in the world. The human mortality rate is over 80%, and it is believed that a single bite from an inland taipan is potent enough to kill 100 healthy adults.

Because there is a mix of many different kinds of poison in the snake’s bite, there are a myriad of symptoms. These include paralysis, internal bleeding, respiratory failure, organ failure, and tissue necrosis. Antivenom for the inland taipan does exist, but bites often result in death in only 30-60 minutes, so getting medical attention in time can prove quite difficult.

Destroying Angel

People sure love to give deadly mushrooms names that indicate just how dangerous they are. Unfortunately the mushrooms refuse to make themselves identifiable, as the destroying angel is often mistaken for the button mushroom, meadow mushroom, and horse mushroom.

Destroying angels are closely related to death caps, and they kill people in the same way. Though considered slightly less potent, as little as half a mushroom cap from a destroying angel can be enough to kill an adult if they don’t receive immediate medical treatment.

With both the destroying angel and the death cap, early treatment is extremely important as the toxins can cause irreversible damage once absorbed by the liver or kidneys. While the mortality rates of these mushrooms have fallen in the last 50 years or so, survivors may still suffer lifelong complications from the damage to their organs. In many cases, the damage may be so severe that while doctors were able to stave off immediate death, the person will need an organ transplant to survive.

Tapeworms

People in the developed world don’t often give a lot of thought to tapeworms. Cases are rare, with less than 1,000 infections in the US each year, and they are easily treatable with antiparasitic medications. Worldwide, however, it is estimated that there are 20 million people with tapeworms, and the parasites claim the lives of over 2,000 people every year.

Tapeworms are usually associated with the consumption of undercooked meat, though humans can ingest tapeworm eggs from tainted water as well. These eggs grow into flatworms that attach to the intestinal lining and absorb nutrients as food passes by them. Different species of tapeworms grow to different lengths, depending on whether the parasites were consumed in beef, pork, or fish, but in the most extreme cases they can grow to be 30 meters long.

There are often no symptoms of a tapeworm infestation, at least at first, though early signs may include abdominal pain, nausea, diarrhea, increased appetite, and weight loss. Though complications from intestinal blockage are possible, tapeworms are more likely to become life threatening if the eggs or larvae enter the bloodstream and travel to other organs.

If the tapeworms reach the brain, liver, or lungs, they can form large cysts that may cause organ failure. In the brain they may also cause seizures or brain damage as well. Not only can these cysts be fatal because of organ failure, but they can also rupture and cause sepsis, which is also deadly.

Poison Fire Coral

Even though mushrooms are technically fungi and not plants, there’s one more species of mushroom we had to mention, if only because of how unique it looks. Most mushrooms have a stem and a cap, but the poison fire coral only has a deep red stem. When they grow in clusters the mushrooms look like red coral, which is where their name comes from. It was thought to be exclusively native to Japan and Korea, but fire coral has recently been found on several Pacific islands and Australia.

It’s been said that simply touching the mushrooms can cause skin irritation, as is the case with some of the other poisonous plants in today’s episode, though these claims are disputed. However, what nobody is disputing is how deadly these plants are when ingested. Just one or two grams of poison fire coral is enough to kill a person.

The fungus contains the toxin Satratoxin-H, the same poison produced by black mold. When fire coral is ingested, it causes stomach pain, damage to the immune system, hair loss, peeling skin on the face, and shrinking of the cerebellum, which results in problems with speech and movement. It can also cause multi-organ failure and necrosis, with organ failure being the main cause of death. This can take anywhere from 48 hours to over a week, depending on how much of the mushroom was consumed, and even those who survive may suffer permanent organ damage.

Lions

It’s probably no surprise that lions, or at least some species of big cat, would have made this list. Lions are so fearsome that they have earned the nickname the “king of the jungle”, despite not even living in jungles.

In terms of raw physicality, humans are completely outclassed by lions. A typical male lion weighs about 190 kg, can reach speeds up to 46 mph, and is several times stronger than a human. And it is the males that are most likely to attack humans, even though females are the primary hunters of the group.

A male lion’s job is to guard the pride and protect their territory, which means that males are more likely to venture outside of their core territory to where they may encounter human settlements. As humans continue to expand their development and encroach on territory the lions believe is theirs, these conflicts have actually been increasing in frequency. Lions are also often drawn to human settlements by the scents of food and livestock, with many attacking and eating livestock.

This can result in attacks on humans as well, and a typical attack from a lion is fatal about 60-70% of the time. But those are attacks from ordinary lions that don’t view humans as food and are merely protecting their own interests. Sometimes, however, lions develop a taste for human flesh.

Or more likely other prey has become scarce, or the lion is too old or injured to hunt anything else. When a man-eating lion attacks a person, the attack is almost always fatal, with survival usually requiring other people with guns or torches to come scare the lion away. But while there was an increase in lion attacks as humans claimed more of their natural habitat, lions only account for about 200 human deaths each year.

Yew Tree

Yew trees have long been popular for landscaping. These evergreen trees can live for thousands of years, and they are tolerant of pruning which made them ideal for use as hedges or topiaries. There was once a time when you couldn’t walk through an American suburb without seeing yews in seemingly every yard, though this has fallen out of favour due to increased awareness of how toxic these trees are.

Every species of yew is highly poisonous, with every part of the tree being potentially deadly to humans except for the flesh of the bright red berries they produce. However, each berry contains a seed, which is the most poisonous part of the plant. These seeds could be broken open while chewing a berry, and they can be dangerous if swallowed as well.

Many poison seeds are able to pass through the digestive system whole without releasing their toxins, but the human stomach is able to break down the outer shell of yew seeds, thus releasing their poison. Eating the needles from the trees is extremely dangerous as well.

The yew contains alkaloids known as taxines, named after the plant’s genus. These tend to cause nondescript symptoms such as headache, nausea, cramps, and vomiting. If a lethal dose is ingested, cardiac arrest leading to death can occur in as little as two hours.

However, an interesting property of the toxin is that it stops cells from multiplying. While this would be a bad thing in general, it has actually proven effective for use in chemotherapy to stop cancer cells from multiplying.

Komodo Dragons

While komodo dragons aren’t the fire-breathing monsters of Arthurian legend, they are still formidable apex predators in their ecosystem. They are the largest extant species of lizards, and the only natural predator of a komodo dragon is a bigger komodo dragon. And yes, they do eat each other.

These giant creatures from the monitor lizard family can be found on the Indonesian islands of Rinca, Flores, Gili Dasami, Gili Motang, and their namesake island Komodo. Attacks on humans by dragons are exceedingly rare for a couple reasons.

To start, the dragons typically flee from humans. We aren’t their natural prey, so they want nothing to do with us. Komodo dragons are also endangered, with an estimated population of only about 3,000, most of which are in Komodo National Park. As such, encounters with the dragons, especially ones that would result with a dragon feeling cornered or threatened, don’t happen often.

When they do though, the bites from these lizards are extremely dangerous to humans, with as much as a 50% mortality rate. While they don’t have anywhere near the bite strength of other reptiles like the crocodile, they instead have sharp, curved, serrated teeth. After biting down, dragons will use their strong neck muscles to shake back and forth, allowing their teeth to tear apart their victim.

Being mauled and torn apart is the primary way that dragons kill, but they have a secondary weapon as well. The serrated edges of their teeth allow bits of food to get stuck in them, and that food then turns into a breeding ground for dangerous bacteria that can cause deadly infections in anything they bite.

There is also some evidence that the dragons may produce venom containing hemotoxins to prevent blood clotting and cause their victims to bleed out faster, though all claims of the venomous nature of komodo dragons are disputed.

Cuckoopint

Cuckoopint is native to Europe, and it is rather abundant as the plants are extremely difficult to remove. The plant thrives in poor growing conditions, and it can fully regenerate from fragments of tubers left behind.

The plant has two main parts: a hood-like sheath known as a spathe, and a long spike with a bulbous cluster of berries at the top. These components bare a strong resemblance to male and female genitalia, which has resulted in the plant having a myriad of nicknames such as Adam and Eve, Cows and Bulls, and Lords and Ladies.

Every part of the plant is poisonous to humans, especially the berries. While it is one of the most common causes of emergency room visits for accidental poisoning, deaths from the cuckoopint are extremely rare. This is because the berries taste absolutely horrible, and there is an immediate tingling sensation in the mouth when the berries are consumed.

This tingling is followed by burning pain of the mouth, stomach pain, and swelling of the throat making it difficult to breathe. Death can result either from asphyxiation if the throat swells shut or from cardiac arrest, but the berries are so unpleasant that consuming a fatal dose of the poison is exceedingly rare.

Polar Bears

Attacks by bears in general are rare, with only about 40 attacks on humans each year. Of those, only 1-3 of those is by a polar bear. But when bears do attack, polar bears are the most likely to prove fatal to humans.

Not only are polar bears the largest bears in the world, they’re also the most likely to see humans as prey. If a grizzly bear attacks you, it’s probably because you were being a dick, or at least were a perceived threat to her cubs. But if a polar bear attacks, it’s probably because it’s malnourished and you are the closest thing in the area that resembles food. Polar bears will even stalk humans as prey when no other food source is available, rather than simply responding to a human that got too close as is the case with most other bear attacks.

Of course, not all polar bear attacks on humans are because they’re starving. Bears are naturally curious creatures, and since a polar bear’s natural habitat is nothing but snow, ice, and delicious seals, literally anything else becomes a major point of interest to them. Typically they will investigate things like campsites or buildings along their migratory route just to see what they are, but once their curiosity has been sated they’ll go on their way.

It is during these investigations, when a person gets too close to a polar bear that was just doing bear stuff, that polar bears will attack humans not for food. This accounts for about a third of polar bear attacks, with the remainder being hungry bears that want to eat people.

Though polar bear attacks have remained rare because they are isolated to arctic regions, in recent decades there has been an increase in the frequency of these attacks as the changing climate alters their normal habitat. Whether this upward trend will continue remains to be seen.

Oleander

Oleander is another popular ornamental plant because of the beautiful flowers it produces. It also produces multiple poisons, such as oleandrin and oleandrigenin. The plants are native to Africa, Europe, and Asia, but they have been cultivated around the world.

The toxins in oleander are cardiac glycosides, which result in nausea, headache, vomiting, weakness, stomach pain, and death by cardiac arrest. All parts of the plant are deadly, and a single leaf is enough to kill a child, with 4 to 10 leaves providing a lethal dose for adults. The leaves can also be brewed into tea that is extremely deadly even in small quantities.

Fortunately, just like some of the other toxic plants we’ve discussed, oleander tastes extremely bitter and unpleasant. As a result, deaths related to oleander are extremely rare, especially in adults. Grazing animals are far more likely to die from ingesting oleander, as just 100 grams of the plant is enough to kill an adult horse.

There have long been concerns about deadly honey contaminated with oleander similar to the mad honey we discussed earlier, but these fears are likely unfounded. While the flowers do require insects to pollinate them, they don’t produce any nectar. As such, bees don’t visit oleander flowers often enough to cause concerns over toxicity of their honey.

Sharks

Sharks are probably the most feared creature in the ocean, regardless of whether or not that reputation is justified. There are over 500 species of sharks, and most of them couldn’t care less about the existence of humans. Of all shark attacks on humans, the vast majority are from three species: the great white shark, the tiger shark, and the bull shark. Of those, there are three times as many attacks from great whites than either of the other species.

However, most shark attacks aren’t fatal. Not because a shark couldn’t easily kill you if it wanted to, because they absolutely can, most of the time they just couldn’t be bothered. If a person is bit by a shark, they invariably respond by flailing their arms and legs, possibly even hitting the shark. But sharks aren’t actually used to prey that are capable of fighting back.

Arguably more important is that one bite is enough for a shark to realize we’re not the kind of meal they’re looking for. Sharks are used to fatty animals that are far more calorie dense than humans and have no way to defend themselves. They may need to take that first bite just to double check, but as a meal for sharks, humans are more trouble than we’re worth.

That said, while most shark attacks aren’t fatal, the mortality rate is still about 15%. There’s also a strong chance of serious permanent injuries, like loss of limbs. It is worth noting that if anything changes within the ocean ecosystem that makes sharks’ usual prey dangerously scarce, humans might suddenly become a lot more appetizing.

Foxglove

Foxglove is the common name for the genus Digitalis, making up about 20 different species of plants. The name Digitalis, from the Latin for “finger”, comes from the long, tubular shape of the flowers, reminiscent of fingers. As for the name foxglove, that is believed to be a corruption or misinterpretation of an older name going back to Old English, when it was believed the flowers were called “fairy glove”.

Many species of foxglove are extremely poisonous, and the toxins can be absorbed by the skin rather than needing to be ingested (though a lethal dose from skin contact is unlikely). Because the flowers have such a distinctive shape and are well known to be deadly, accidental consumption of foxglove is extremely rare. It also tastes so horrid that people typically spit it out immediately before swallowing any of the poison.

When it is ingested, however, the toxins are so potent that a single leaf is deadly to a child and only 2-4 leaves are deadly to an adult. Early symptoms of nausea, vomiting, and diarrhea begin within an hour of consuming foxglove, followed by tachycardia and bradycardia. Death by cardiac arrest usually occurs within just a few hours of consuming the plants.

Although people know to stay away from foxglove, the plants are most dangerous in their first year. Foxglove doesn’t flower until its second year, so in the first year its clusters of leaves are sometimes mistaken for the much safer plant comfrey. Most deaths from foxglove poisoning are the result of this misidentification, as people will use the leaves to brew tea.

Humans

Yes, we realize that ending this list with humans may feel a bit lame, but the numbers don’t lie. And really, since humans don’t have any natural predators and are generally smart enough not to eat things that have been identified as fatally poisonous, it only makes sense that one of the most deadly things on the planet to humans would be other humans.

Each year, there are over 450,000 murders around the world. That number only includes homicides, not people killed during armed conflicts between nations. Armed conflicts account for roughly 90,000 more deaths each year. This also only includes deaths that were ruled as homicides, not those cases where someone slipped and fell onto a knife 17 times. Admittedly though, that category of deaths is rather small.

As staggering as that number of homicides is, it pales in comparison to the over 700,000 suicides each year. With people being responsible for over a million human deaths each year, we truly are our own second worst enemy. Mosquitoes are still public enemy number one.

Key Takeaways

• The box jellyfish is the most venomous marine animal, with the Australian species capable of killing 60 adults and acting extremely quickly.,The castor bean contains ricin, a deadly toxin with no antidote, that can kill an adult with just one milligram.,The black mamba is Africa’s deadliest snake, with a near 100% mortality rate when untreated, due to its highly venomous and aggressive nature.,The death cap mushroom is deadly due to its resemblance to edible varieties and pleasant taste, with a mortality rate that has decreased to 10-30% thanks to medical advancements.,Mosquitoes are the number one killer of humans, causing up to 3 million deaths annually through diseases like malaria, dengue, and Zika.

Sources

• Original Side Projects video: 50 of the Deadliest Plants and Animals on Earth
• Hero image source by Tisha Mukherjee / openverse, by-sa.

Related Coverage