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Poison vs. venom: What's the difference? - Rose Eveleth
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Poison vs. venom: What's the difference? - Rose Eveleth

 
Would you rather be bitten by a venomous snake or touch a poisonous frog? Wait, what's the difference between poison and venom, anyway? Let's say you have the misfortune to be bitten by a venomous rattlesnake. When it bites you, the snake will eject venom from little sacks behind its eyes, through its hollow fangs and into your flesh. That venom will then travel through your bloodstream and all over your body. In most cases, snake venom contains neurotoxins, proteins that can do all sorts of nasty stuff like make your muscles fire uncontrollably, burst your blood cells, and make you go completely numb. But you might get lucky! Snakes don't always decide you're worth wasting venom on. In fact, between 20 and 80% of snake bites are so-called "dry bites," where the snake is just trying to send a message without actually killing you. You see, venom takes energy and resources for the snake to make, and they don't want to waste it on a warning shot. When it comes to poison, on the other hand, there's no warning shot. If you pick up a poisonous dart frog to admire its beautiful colors, you've already gotten deadly poison all over your hands. As it seeps into your skin and travels through your blood, the poison starts to interfere with your nerves, preventing your muscles from contracting. If the frog's poison reaches your heart, it can cause it to stop. The distinction between venom and poison is purely in the method of delivery. Poison has to be inhaled, ingested, or absorbed. Venom has to be injected into a wound. Chemically, venoms and poisons are both considered toxins, so a snake bite is venomous. A poison dart frog is poisonous. Brown recluse spiders are venomous. Lionfish and pufferfish are poisonous. And some compounds can be poisons in one animal and venoms in another. Tetrodotoxin, a chemical 10,000 times more toxic than cyanide, is found in pufferfish, where it makes them poisonous. It's also found in the deadly blue-ringed octopus, where it's a venom delivered by bite. Some animals can even be both poisonous and venomous. Take the Asian tiger snake, for example. Not only does it have venom in its fangs but it also absorbs the toxins from the poisonous toads it eats, and then secretes those toxins from special glands on its neck, rendering it poisonous, too. Scientists are constantly finding new animals that employ toxins in weird, interesting ways. Recently, researchers discovered the very first venomous crustacean. Out of 70,000 species of crustaceans, only this one little remipede is venomous. Speleonectes tulumensis has figured out how to create a cocktail of toxins that it delivers through its tiny fangs. Scientists aren't totally sure how this venom works yet, but they think that it causes the unwitting victims' neurons to fire over and over and over again until it becomes paralyzed. Then, the little remipede closes in, dissolving away the exoskeleton of its prey and sucking out the juices. But poisons and venoms aren't always all bad. For thousands of years, humans have looked for ways to harness the power of these toxic compounds for good. Today, we have all sorts of medicines that come from toxins. The poison from cone snails is used as a painkiller. Many poisonous plants have been used to treat everything from malaria to irregular heartbeats. And scorpion venom might one day be used to treat heart disease. So, what should you do if something bites or poisons you? Don't try any of the things you've seen on the internet or in movies! Don't try to capture and kill the animal that bit you, and don't use a tourniquet or knife on your wound. Most importantly, don't panic! Stay calm, and seek medical attention. Treatment will mostly depend on what species you encountered. But if you forget the distinction between poison and venom, and tell the parademics that you were poisoned by a viper, they'll probably forgive you and treat you anyway.

Rose Eveleth, TED-Ed, TED, TEDEducation, TED Ed, poison, vernom, poisonous, venomous, toxins, snake, rattlesnack, treat poison, Franz Palomares

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