Lionfish on a mesophotic reef off Florida. Photo credit: Mike Echevarria, Florida Aquarium via NOAA
In the last few decades, scientists have come to appreciate the incredible creatures living on the reefs that lie just below conventional diving limits in what is called the mesophotic zone. These incredible biodiversity hotspots are home to more endemic species than shallower reefs, and conservationists are hopeful they may serve as refuges—pockets of relatively pristine habitat out of reach of anthropogenic stressors—where species under threat from pollution, overfishing, and even the effects climate change can hang on while we clean up our act.
A shield-snouted brown snake (Pseudonaja aspidorhyncha) from Northern Territory, Australia. Photo by Christopher Watson
There’s an age old belief that baby snakes are more dangerous than adult ones. There are generally two proposed reasons why this could be: either a) young snakes have yet to learn how to control how much venom they inject, so they deliver all of their venom per bite, or b) that because the snakes are smaller, they need more potent toxins to successfully take out their prey. The first is misleading, because even if baby snakes did dump all their venom into each bite, they still have so much less venom than adults that it doesn’t matter (and there isn’t any real evidence they lack self-control*). The second, though, warrants closer investigation: do younger, smaller snakes really have deadlier venoms? A new study on brown snakes in Australia says no—and in fact, the opposite can be true. Continue reading “Older, wiser, deadlier: “blood nuking” effects of Australian brown snake venom acquired with age”
Scientists refer to the study of biological toxins as toxinology. From bacterial toxins like anthrax to the deadliest snake venoms, toxinology examines the chemical warfare between animals, plants, fungi and bacteria. In my Toxinology 101 series, I explain and explore the fundamentals of toxin science to reveal the unusual, often unfamiliar, and unnerving world created by our planet’s most notorious biochemists.
One of the most frequent questions I receive as a venom scientist (so much so I dedicated an entire chapter of my book, Venomous, to it) is some variant of What is the deadliest toxic animal? While that seems like there should be an easy answer, as with anything in the natural world, defining deadliness is messy. To answer that question, you have to be clear about what you’re reallyasking. Is the subtext of the question What animal is most likely to kill me? Or What animal should I be most afraid of running into? Or more simply, What animal produces the most potent toxin, because I’m a biochemistry nerd and I’m just curious? Each of those questions is answered a bit differently, and even still, it’s complicated. Continue reading “Measuring Deadliness | Toxinology 101”
As the March for Science has drawn near, scientists and science-lovers across the country have pontificated at length on why they are—or aren’t—marching. But while today’s 400-plus demonstrations around the nation will hopefully resonate with lawmakers, it takes more than rallies to accomplish lasting change. The following is a guest post from Dr. Kira Krend, a biology teacher in Honolulu, HI, on her March for Science—one that she does every day.
13,407 steps.
The display on my fitness watch tells me that this is how far I’ve walked so far today. It’s only 2:33 pm. I haven’t finished setting up for the lab tomorrow, and a stack of ninety-eight tests sits on my bag so I don’t forget to bring them home to grade tonight. In the next five minutes, I have three students stop by:
“Dr. Krend, can I come to class 30 minutes late tomorrow?” (No.)
“Hey Dr. K., do you have any food?” (I have some apple slices. No? Okay.)
“We found a baby bird downstairs, can you come help us with it?”
Sigh. That last one’s going require me to walk a lot more steps. Setting up for the lab is going to have to wait.
I’ve been watching my liberal scientist-filled Facebook feed blow up with March for Science posts since January. I appreciate the creatively knitted caps, witty slogans on signs, and inspiring reasons they are marching for science around the world on Earth Day 2017. I have no problem with the march today; in fact, the profound belief in the value of the intersection between science and public has been a driving factor in my life.
I decided to march for science before it was cool: I am a Ph.D. who chose to teach high school biology.
By tweaking a compound from bee venom, scientists may have created a molecular Trojan horse to deliver drugs to our brains. Photo by Flickr user joeyz51
We human beings are quite fond of our brains. They are one of our largest and most complex organs, weighing in at nearly three pounds (2% of our bodies!). Each contains upwards of 90 billion neurons responsible for controlling our gangly, almost hairless primate bodies as well as processing and storing a lifetime’s worth of events, facts and figures. So we protect our brains as best we can, from hats that battle temperature extremes to helmets that buffer even the most brutish blows.
Our bodies, too, protect our brains vigilantly. Select few compounds are able to cross the blood-brain barrier, a membrane which shields our most essential organ from the hodgepodge of potentially-damaging compounds that might be circulating in our blood. The staunchness with which our brains are guarded internally is usually great—except, of course, when doctors need to deliver drugs to brain tissues.
It’s not too hard to get some molecules across, assuming they are small and/or fat-soluble, like many anti-depressants, anti-anxiety meds, or notorious mind-altering substances like alcohol and cocaine. But larger molecules, even important ones like glucose, have to be specifically pulled across this divide between our blood and our brains. That means that some life-saving drugs, such as chemotherapy agents targeting brain tumors, need help getting into our heads. And that is where the newest venom-derived product—MiniAp-4—comes in. Continue reading “Bee derived molecular shuttle is the newest buzz-worthy venom product”
The seven-arm octopus, Haliphron atlanticus, lives a hidden life deep in the dark depths of the oceans. These massive cephalopods—females of which can grow to be more than 12 feet long—earned the moniker for their habit of folding one of their eight arms away. What little is known of their daily lives has largely been gleaned from dead animals pulled from the sea by trawls, as inhabitants of the deep sea, their activities are nearly impossible to observe. Now, a new paper in Scientific Reports provides insights into their diet and behavior, finding they prefer to dine on species we tend to think of as less than palatable: jellyfish. Continue reading “Jelly Belly: Elusive Deep Sea Octopus Takes Its Gelatinous Meals To Go”
Meiacanthus atrodorsalis—a pretty little fish with a venomous bite. Photo by Klaus Stiefel via Flickr
“Did you tell her the one about George Losey and the blenny?” Rich Pyle asked with a knowing smirk. Pyle and I were sitting in the living room of legendary ichthyologist Jack Randall for a piece I was writing about him for Hakai Magazine. “It’s a good venom story,” Pyle continued, grinning.
Randall’s eyes lit up with mischievious joy as he launched into the tale. He and George Losey were invited to Guam to bear witness to a massive crown of thorns sea star invasion, he explained (“It was one overlapping another as far as you could see,” he recalled; “They decimated the corals of the whole northern coast”). While he and Losey were diving, Randall saw a small blenny—one of a group of blennies that he knew Losey had taken an interest in. Since he had a three-pronged sling-style spear on him, Randall caught the fish, which remained wriggling on the end of his spear tip. He asked Losey if he wanted it to examine later, and Losey did, but he didn’t have any containers to put it in. So, Losey did what seemed like the obvious thing: he tucked the creature into his swim trunks. “Well, it has a venomous bite…” Randall said laughing—a fact which was unknown at the time. “It bit him right here, on the belly,” Randall gestured, “and he let out a yelp!” That was how George Losey first discovered the venomous nature of fang blennies in the genus Meiacanthus, Randall explained—by making the mistake of putting one in his shorts. Continue reading “Beware the blenny’s bite: scientists uncover the toxins in fang blenny venom”
UCI chemistry professor Ken Shea (right) and doctoral student Jeffrey O’Brien (left) have developed a potential new broad-spectrum snake venom antidote. Photo credit: Steve Zylius / UCI
Living in countries like the U.S., Australia, and the U.K., it can be all too easy to forget that snakebites are a serious and neglected global medical problem. It’s estimated that upwards of 4.5 million people are envenomated by snakes every year; about half of them suffer serious injuries including loss of limbs, and more than 100,000 die from such bites.
Much of this morbidity and mortality could be prevented if faster, easier access to the therapeutics that target and inactivate snake venom toxins could be established. But effective antivenoms are difficult to produce, expensive, and usually require storage and handling measures such as refrigeration that simply aren’t possible in the rural, remote areas where venomous snakes take their toll. Seeking to solve many of the issues, a new wave of researchers have begun the search for alternatives, hoping to find stable, cheap, and effective broad-spectrum antidotes to snake venom toxins. One such group at the University of California Irvine recently announced a promising new candidate: a nanogel that can neutralize one of the most dangerous families of protein toxins found in snake venoms.
Scientists refer to the study of biological toxins as toxinology (not to be confused with toxicology, with a C—as I explain below). From bacterial toxins like anthrax to the deadliest snake venoms, toxinology examines the chemical warfare between animals, plants, fungi and bacteria. This is the first in a new series I call Toxinology 101, where I explain and explore the fundamentals of toxin science to reveal the unusual, often unfamiliar, and unnerving world created by our planet’s most notorious biochemists.
“Point blank,” my friend, a commander in the US Navy, said firmly, when I asked what misused word or phrase really gets under his skin. “Definitely point blank.”
I asked why, and as he explained, I realized I’d been using the phrase wrong, too. To people familiar with firearms, hearing someone call an up-close gun shot “point blank” is like dragging nails on a chalkboard because that’s not what it means at all. Point blank (which may come from the French phrase pointé à blanc, referring to an arrow being aimed at a white spot at the center of a target) has nothing to do with close proximity to the shooter. Rather, point blank range is the distance at which a weapon aimed at a target succeeds in hitting it—where point of aim (e.g. the middle of the crosshairs) is the same as point of impact.
Bullets don’t travel in a straight line; from the moment they leave the gun, they are pulled by gravity. The further away your target is, the more you have to adjust for the arc of the bullet with the angle of the barrel of the gun. But the aiming line of sight is a straight line; point blank is where the bullet’s path and the line of sight cross. Adjustable sights allow you to aim your shot for a desired distance; thus, for long-range rifles, “point blank” could be set to 100, 200, or even 300+ yards away. Meanwhile, many handguns have fixed sights, so their point blank range is limited to whatever distance the gun is is zeroed to. Point blank range for such guns can be somewhat close—within fifty feet—but even that is much further than what most people think of as “point blank.” In fact, if a gun is literally pressed against the victim, then the point in the middle of the sights (which are usually on top of the barrel) isn’t where the bullet ends up—it’s off by the width of the barrel at least—so that isn’t point blank range. Different munitions have different maximum point blank ranges, depending on the weapon’s inherent ballistic properties, the aiming device used, and the type of bullet used.
A quick diagram showing how “point blank” can be somewhat close or hundreds of yards away.
It’s no wonder, then, that every time my friend hears someone was shot “point blank” (meaning gun to the head, or within a few feet), he gets a little prickly. Of course, there are words and phrases like “point blank” for every profession. Doesn’t matter if you’re an accountant, mechanic, or CEO, your job requires an understanding of the lingo of your field, and it can be frustrating when words with specific, important meanings are flung about incorrectly by everyone else.
For me, the ‘nails on chalkboard’ feeling comes whenever I hear people talk about their everday exposure to “toxins” or “poisonous” snakes. Though they’re often used interchangeably, the words toxin, venom, and poison (and their corresponding adjectives toxic, venomous, and poisonous) have very distinct meanings to toxinologists. So, it’s only fitting to kick off my Toxinology 101 series by explaining the differences between them and when it’s appropriate to use each of these terms. Continue reading “What’s in a name? Venoms vs. Poisons | Toxinology 101”
The deadly boomslang, the snake fingered in the death of Dr. Karl Schmidt. Photo by William Warby
The actual bite happened in less than a second. Dr. Karl Schmidt, an American herpetologist at the Field Museum in Chicago, had been sent a live snake to identify by his colleague, Richard Marlin Perkins (then the director of the Lincoln Park Zoo). The animal appeared to be a boomslang (Dispholidus typhus), a kind of rear-fanged African snake, but there was something a bit odd about its scales, so Schmidt and his colleagues discussed the matter as they examined the serpent. It didn’t take long for the agitated animal to decide it had had enough manhandling. “I took it from Dr. Inger without thinking of any precaution, and it promptly bit me on the fleshy lateral aspect of the first joint of the left thumb,” Schmidt wrote in his diary on September 25th, 1957. “The mouth was widely opened and the bite was made with the rear fangs only, only the right fang entering to its full length of about 3 mm.” A day later, he would be dead. Continue reading “Bite from the past: new study on boomslang venom provides insights into the death of renowned herpetologist Karl Schmidt”
