Christie Wilcox examining a bullet ant at the Tambopata Research Center in the Peruvian Amazon. Photo by Aaron Pomerantz
A large dose from the dreaded Australian box jelly, a.k.a. Chironex fleckeri, can kill a grown adult in a matter of minutes. Even small jellyfish can pack potent toxin, such as the matchstick-sized Irukandji box Jelly, whose venom can kill a human in as little as four hours, though its immediate effects sometimes go unnoticed. As a species, human beings have an inborn and intrinsic fear of jellyfish, spiders, snakes, and all things poisonous. From a young age, we are conditioned to avoid these creatures like the plague, but venom and poison are more than just an organic weapon found in nature, and studying toxins can reveal a lot about life and evolution.
In her new book, 'Venomous: How Earth's Deadliest Creatures Mastered Biochemistry' (out August 9 on Scientific American/Farrar, Straus, and Giroux), molecular biologist Christie Wilcox explores the culture and history of venom. Weaving together research, personal narratives, photos, and diagrams, the author paints a vast portrait of poison, including descriptions of the venom found in spiders, snakes, octopi, urchins, Komodo dragons, duck-billed platypuses, ants, cone snails, as well as in-depth explanations on how each defense tool affects victims. Wilcox goes on to argue that the animals we grew up fearing now hold the key to life. She details how venom can be used to treat numerous ailments, such as high blood pressure and erectile dysfunction, plus illnesses that currently do not have cures.
No stranger to encounters with these poisonous creatures, Wilcox brings years of personal insight to her research and analysis. She's cataloged the venom of a myriad of creatures in locations as disparate as the beaches of Indonesia and the rainforests of Peru. By studying the evolution, adaptation, and immunity of poisonous creatures, Wilcox hopes Venomous will both lead the conversation about the groundbreaking research in the scientific community involving venom, as well as enrapture the average zoology enthusiast curious about snake bites. VICE sat down with her for a chat about her interest in venomous creatures, the medical benefits of venom, and how some cultures use venom to get high.
Christie Wilcox, photo by Aaron Pomerantz
VICE: How did you first get interested in venomous creatures?
Christie Wilcox: I've loved animals of all kinds since I can remember. I was that kid, the one you'd find chasing snakes or poking at jellyfish that washed up on the beach. The species that others feared fascinated me. But I would say my obsession with venomous animals didn't fully blossom until I was thinking about what I wanted to do for my dissertation. After I started lion fishes, I became completely infatuated with venoms and venomous animals, eager to learn everything there is to know about them.
Humans have an innate fear of poisonous creatures. When we see a snake or spider, it's like an alarm bell goes off in our head. How did this relationship develop?
We know that our relationships with many venomous animals goes back thousands of years. They are depicted in some of our earliest artwork, and appear as heroes and villains in our oldest myths and legends. But there is some evidence that our relationship with these menacing creatures dates back even further than that, to the early origins of our species, perhaps even our lineage of primates. Snakes, in particular, are instantly recognizable to humans and apes alike. We can see a snake in a picture and react with fear even before we know that we're seeing it. Even young children and infants react to videos of snakes with fear, long before they could have learned such a response from their parents, which suggests that our fear of snakes is innate, ingrained into our DNA through millennia of coevolution.
When did scientists first start cataloging and researching venomous creatures? How far do the records go back?
We have made note of venomous animals for as long as there is recorded history. Many famous naturalists, doctors, and philosophers were aware of nature's little biochemists, and often spoke or wrote of their dangers. You can find references to species like stingrays, snakes, and spiders in the writings of Aristotle, Plato, and Pliny. As scientific inquiry became more formal (the word "scientist" didn't emerge until the 1830s), so, too, did the study of venomous animals. The effects of their venoms and methods of treatment can be found in some of the oldest medical texts, dating back centuries. Still, we have only scratched the surface when it comes to the rich resource of knowledge these animals represent. Most research has focused on easily accessible venoms, leaving the vast majority of venomous species unstudied.
'Flight of the Mongoose and the Serpent Armies,' a watercolor depiction of the age-old battle between snake-eaters and their prey. Image courtesy of Wilcox.
What does this book add to the study of venom and anti-venom that was previously not available to the public?
When Greg Laden reviewed the book for ScienceBlogs, he gave it what I consider to be the highest praise possible: He said that he learned something new on every page. I think this book takes the scientific papers on venom, which scientists have access too, and translates them and presents them to the reader in an engaging and accessible way.
During your research, did you discover any weird stories or unexpected findings?
The most unexpected story was how there are people who use venoms recreationally, claiming it's a better high than heroin. In the medical literature, there are several papers describing people paying for bites from deadly species like cobras to get their fix. Cases are few and far between, but I was shocked there were any cases at all.
Could you imagine humans experimenting with venom-based drugs to get high in the future?
There's no doubt that our species has a preoccupation with mind-altering substances. So it's not surprising that people have experimented with anything they think might get them high, and venoms are no exception. I think the danger factor and difficulty of obtaining and maintaining animals for their venom has so far prevented illicit uses from going mainstream, but cases of using venomous animals recreationally can be found in places with long cultural histories with these animals, such as India. Personally, I wouldn't want to risk a cobra bite, even if it was the purest, most incredible high on Earth.
Are there any misconceptions or urban legends that you disproved or found valid while writing the book?
There are lots of misconceptions about venoms, mostly related to how to treat bites or stings. For example, you might have heard you should pee on a jellyfish sting. This is bad advice. Urine can induce stinging cells to fire, injecting you with even more potent, painful venom. Instead, you should douse the area with vinegar, which inhibits stinging. Or, you might have heard that you should suck snake venom out of a bite—not so! You're not able to remove the venom that has been injected like that, so sucking is a waste of time. Instead, focus on getting the victim medical aid.
A speckled rattlesnake, photo by Chip Cochran
Why did you think these creatures develop venom?
There are all sorts of reasons to develop venom. Some species use their potent chemical cocktails to take down prey that would otherwise be unavailable to them, while others use their toxic mixes to ward off potential predators. Platypuses even use venom in battles over females! So, "why" varies. All of these uses can be boiled down to: venom helped each venomous species survive and reproduce better than similar animals without it. Once a lineage started down the evolutionary path to creating venom, natural selection honed the toxin mixtures, creating potent and effective toxins. How they start down that venomous path remains somewhat of a mystery.
For some species, we can connect the evolutionary dots, connecting venom toxins to things like antimicrobials found in saliva. Thus, we can deduce that the venom form evolved out of a duplication event which created an extra gene for natural selection to work with. But in many cases, we don't know exactly where a toxin came from, or even how an entire venom system came to be. Venomous animals still have many secrets to tell which will further our understanding of how evolution works.
How do animals like the mongoose develop immunities?
There are two main ways that an animal can be innately immune or resistant to a particular kind of venom: either they have altered their own bodies to make it so the toxins don't work, or they produce some kind of venom-inactivating compounds in their blood. Mongooses are an example of the former path. They are essentially immune to cobra venom because they have mutations in the ion channels that the lethal toxins in cobra venoms target. Other animals, like opossums, produce special proteins that bind venom toxins, making them useless. These compounds are especially exciting to scientists, as it is possible that they could be modified and used to treat snakebites in people.
In addition to innate immunity, many animals can become resistant to venoms much in the same way vaccines make us resistant to diseases, through the production of specific antibodies. If non-lethal doses of venom are introduced repeatedly over time, the adaptive immune system may be able to create antibodies which target venom toxins, binding and removing them from the blood. This is how scientists make the anti-venoms that are used to treat the deadliest venoms. They repeatedly inject small doses of venom into an animal like a horse or a sheep and then extract and prepare the venom-binding antibodies for human injection. It's not a perfect process—some toxins aren't terribly good at activating the immune system, and thus slip through the cracks. Others are too locally toxic that it's impossible for injected antibodies to arrive at the site in time.
What does venom teach us about evolution?
Venoms are unique and fascinating adaptations. There are hundreds of thousands of venomous species littered amongst the sundry branches of the tree of life, from some of the oldest invertebrates, to insects, reptiles, mammals, and even some of our recent kin (like primates). Many of these venomous lineages evolved their toxic cocktails independently, thus by studying these groups and the toxins they wield, we can gain a better understanding of how novel adaptations arise.
We can also better understand the limits of natural selection by looking at what kinds of molecules are co-opted for nefarious purposes, such as making a venom-derived biological weapon. And lastly, in many venomous lineages, there are also non-venomous animals who have secondarily lost their toxicity, like the Marbled Sea Snake, which lost its venomous abilities. To really understand evolution, we have to understand how and why traits are lost, in addition to how and why they are gained. So by studying species that no longer bite or sting, we can gain a more complete picture of the often mysterious nature of evolution and natural selection.
The venomous spur of the platypus. Photo by Christie Wilcox
How can venom help us in the future and what can it treat?
We've only just begun to investigate how venom toxins can help us medically. Every venomous animal has a unique chemical cocktail made from dozens to thousands of compounds, many of which have pharmacologically-useful effects on our bodies, such as lowering blood pressure or killing cancerous cells. So far, there are six venom-derived drugs approved by the FDA, with many more in various stages of testing and clinical trials. So far, the possibilities seem endless. There are venom compounds which appear to tackle the world's most notorious diseases, from diabetes to Alzheimer's, and ones for more minor conditions, including erectile disfunction and crow's feet.
And that's just what we've found so far with the relatively few animals whose venoms have been characterized. There are hundreds of thousands of venomous species whose venoms have never been studied, any of whom might be harboring the next blockbuster drug. If we don't conserve our venomous biodiversity, and let habitat destruction, pollution, and climate change wipe them from the face of the Earth, then we will lose invaluable biochemical resources that we can never replace.
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