Don’t Pee On It: Zinc Emerges As New Jellyfish Sting Treatment

Biochemist and venom expert Angel Yanagihara

Nothing can turn a fun day at the beach into a nightmare faster than a jellyfish sting, as Angel Yanagihara, researcher at the University of Hawaii, learned firsthand when she was swimming off Kaimana beach in 1997. She had never heard of the nastiest group of jellyfish, the cubozoans (better known as box jellies), until she was badly stung. “I made it back to the beach in excruciating pain but then lost consciousness,” she recounts. “I was bed ridden for days in great pain and none of the approaches I tried brought any relief.” While the encounter was devastating, as a biochemist, Yanagihara was intrigued. She began scouring the scientific literature to find out what caused her traumatic ordeal, only to find out no one knew what was in box jelly venom. She has been studying the animals ever since.

When human flesh brushes up against a jellyfish tentacle, the tiny stinging cells jellies carry, called cnidocytes, can discharge their painful venom in as little as 700 nanoseconds. During the winter months, Australian waters are home to an abundance of the deadliest jellyfish in the world, the box jelly Chironex fleckeri, which has been known to kill a person in less than five minutes.

The deadly but beautiful Chironex fleckeri

Chironex even looks scary, with a bell that can be large as a basketball and tentacles up to ten feet long carrying millions upon millions of stinging cells. But Chironex didn’t earn its title as the deadliest jellyifish in the world based on looks. Anyone who has come in contact with Chironex knows its fearsome reputation is justified, as even mild stings are excruciating. Yet despite decades of research, exactly how Chironex and other jellies deal their sometimes-fatal blows has remained a fearsome mystery.

“For over 60 years researchers have sought to understand the horrifying speed and potency of the venom of the Australian box jellyfish, arguably the most venomous animal in the world,” explains Yanagihara. It’s not that scientists have been unable to isolate any toxins. Yanagihara’s initial work discovered pore-forming toxins called porins in a related species, Carybdea alata, capable of tearing holes in blood cells, and since scientists have found similar porins in every jellyfish species they’ve looked at. The conundrum is that severe sting victims don’t suffer from profound destruction of red blood cells, seemingly counting out the porins as the cause of fatal stings. But if it’s not the porins, what in jellyfish venom is to blame? How does it act so quickly, leading to such sudden cardiovascular collapse? And is there anything we can do to slow or stop its deadly activity?

Now, in a new paper published today in PLOS ONE, Yanagihara and her colleagues from the University of Hawaii have revealed the key mechanism by which Chironex venom—and, specifically, the overlooked porins—quickly dismantle the cardiovascular system. Armed with physiology, the team was able to find a safe treatment that could be used to improve survival in sting victims.

Yanagihara collecting Hawaiian box jellies

It’s virtually impossible to find a good treatment for a toxin without first knowing what it is. So, the first step for Yanagihara was to isolate jellyfish venom and figure out if the porins were the real culprits. For species like snakes and spiders, this is a straightforward process, as they possess glands with large volumes of venom. But you can’t just have a jelly bite a container or pull venom from a cnidocyte using a syringe; minuscule amounts of venom components are stored in microscopic compartments amongst a plethora of other body parts—deadly needles in haystacks of cellular debris. Yanagihara spent years troubleshooting and perfecting a new method of venom extraction to yield potent venom free of as much junk as possible. With this in hand, she was able develop assays to visualize how the venom acts both on red blood cells and in live animal models.

Ring-shaped pores in the wall of a red blood cell from jelly porins

Yanagihara used electron microscopy to visualize the venom’s affects on blood cells, and as suspected, found that venom porins create holes that lead to cell rupture. But as previous clinical research had shown, the cells bursting wasn’t the real issue; Yanagihara found that instead, for several minutes before they break apart, red blood cells leaked potassium. Animal models confirmed that this sudden spike of potassium in the blood stream, termed hyperkalemia, is what leads to rapid changes in heart rate and function and, ultimately, the cardiovascular collapse that causes death by jellyfish. With the physiology of stings revealed, Yanagihara could finally start the laborious task of finding a way to stop the venom in its tracks.

Jellies aren’t the only animals that create porins. “The structural motif of the cubozoan porin reminded me of the bacterial porins,” said Yanagihara. “I scoured that literature to look for inhibitors of the self assembly of those pore forming toxins and discovered studies from the 1940s even as far back as the 1890’s citing zinc ion as useful in the inhibition of bacterial driven lytic reactions.” Yanagihara tested over 100 compounds to see if they inhibited jellyfish venom, and found that one of the safest—zinc gluconate—worked well.

Scientists aren’t 100% sure how zinc compounds inhibit the porins, but they believe that the zinc disrupts the binding domains necessary for the proteins to assemble to form pores. In in vitro models, Yanagihara found that a low dose of zinc gluconate completely prevented the venom’s blood cell busting effect. She then tested the compound in animal models, and found it worked better than the commercially available antivenom for box jelly stings, keeping the mice alive more than twice as long as the antivenom.

Yanagihara preparing the topical treatment for Nyad

Yanagihara is now investigating how to turn the compound into a treatment for human stings. She has created a topical version, which was tested on extreme swimmer Diana Nyad when she attempted to swim a record-breaking 103 miles from Cuba to Florida. Nyad attempted the swim in 2011, but was stung so severely by box jellies on the first day in the water that she had to stop after 29 hours. This time, armed with Yanagihara’s treatment, she swam three nights through dense jelly aggregations, and kept at the swim for a total of 51 hours covering over 60 miles of the trek before she gave in. Nyad reported that the treatment blunted the stings to her exposed lips and face enough to keep her going.

Zinc gluconate isn’t a cure-all; it won’t stop all of the excruciating pain associated with severe stings, and victims are still at risk of going into shock and cardiovascular failure. But, Yanagihara is hopeful that treatment with zinc gluconate might be effective enough at prolonging survival in severe sting victims long enough to get them to medical professionals that can save their lives, and may provide welcome relief to mild sting victims. Currently, vinegar is used to treat jellyfish stings, though it only prevents unfired cnidocytes from contributing to the sting and doesn’t act on the venom itself. Hot water can provide temporary relief, but Yanagihara is hopeful that zinc treatment will prove a more viable solution.

In Australia and other areas of the Pacific where Chironex roams, such a solution is desperately needed. Despite being home to ten of the worlds deadliest snakes, since 1980, there have been more deaths due to jellies than snakebites in Australia, and it’s estimated that 20-50 people die annually from box jelly stings in the Philippines. Worse, in recent years, scientists have reported that expanding ranges for many jellyfish species due to changing ocean currents, over-fishing of other species, and warmer ocean temperatures from climate change. The Nation Science Foundation estimates that jellies cost hundreds of millions or even billions of dollars in medical damages, fisheries effects and tourism loss. This breakthrough treatment is more important than ever, and hopefully, will help relieve the thousands of stings worldwide every year.

Citation: Yanagihara AA, Shohet RV (2012) Cubozoan Venom-Induced Cardiovascular Collapse Is Caused by Hyperkalemia and Prevented by Zinc Gluconate in Mice. PLoS ONE 7(12): e51368. DOI:

Photo credits: Angel Yanagihara taken by Laura Aguon; Chironex fleckeri by Dr. Robert Harwick; Box jelly collecting by Keoki Stender; Pores in RBC from the paper itself; Yanagihara prepping treatment by Christi Barli (all images provided by Angel Yanagihara)

Plant’s Cry For Help Attracts The Wrong Crowd

A simple white butterfly caterpillar (Pieris rapae) nibbles blissfully on a cabbage leaf, completely unaware of the complex interspecies interactions he has just set in motion. The cabbage, displeased with the damage the caterpillar is doing to its tissues, is releasing volatile compounds into the air, hoping to attract parasitoid wasps like Cotesia glomerata, which use caterpillars like the one eating through the cabbage’s precious leaves as incubators for their larvae—and succeeds. Drawn by the compounds wafting off of the damage plant, a female wasp arrives and finds the defenseless caterpillar. Using a needle-like appendage, she injects her eggs into the caterpillar’s body, and her larvae hatch and feed on the caterpillar’s internal organs one by one, carefully selecting the least important so that their meal survives as long as possible. Finally, when they are ready to pupate, the wasp larvae tunnel out, and through a chemical trick, convince their half-dead host to spin them a protective web of silk. Success, thinks the plant (if plants could think); its cry for help has stopped another hungry caterpillar in its tracks.
Lysibia nana parasitizing cocoons of Cotesia glomerata

But, as Dutch scientists have discovered, the story doesn’t end there. What goes around comes around for the C. glomerata, as there are other wasps that use them as hosts, laying eggs in the wasp larvae that grew in the caterpillar, like a parasitic Russian doll. Researchers have discovered that these hyperparasitoids (parasitoids of parasitoids) can smell the call being broadcast by the plant, too.

After all, the world is a large place. Parasites that need to find a very specific, small host benefit from having a way of finding what they need without wasting tons of energy searching. So it makes sense that Cotesia glomerata and other parasitoid wasps with caterpillar hosts are drawn to the chemical compounds emitted by damaged plants. If they’re drawn, the wasps that parasitize them should be drawn, too. So the team tested this hypothesis by collecting air from undamaged plants, plants damaged by uninfected caterpillars, and plants damaged by caterpillars already infected with parasitiod wasp larvae, then presented those scents to hyperparasitoid wasps to see if they were attracted to them.

Not only were the wasps attracted to the smell of caterpillar damage in general, “we found that they preferentially detected odours of plants damaged by infected caterpillars,” explained Dr Erik Poelman, lead author of the study published today in PLoS Biology. The wasps were nearly five times more attracted to the damage done by infected caterpillars. “We were excited by these results as they indicate that hyperparasitoids rely on a network of interactions among plant, herbivore and parasitoids to locate their host”.

But how did the wasps detected whether the caterpillars were infected? Poelman and his team wanted to find out. It’s known that infection can change the saliva contents of caterpillars, so they took the saliva from uninfected and infected caterpillars and presented those scents to the wasps, but the wasps didn’t care. So while the infection is altering the caterpillar’s saliva, the change in attractive chemicals had to be coming from the plant. They then tested the different air collections for volatile compounds, and found the ones damaged by caterpillars infected with Cotesia glomerata were only 40% similar to the ones damaged by uninfected caterpillars. Something about infection changes the saliva in a caterpillar, which in turn affects what volatile compounds a plant emits when it gets damaged by that saliva.

This complex web of interactions calls in to question the role of the plant compounds in the first place. Though they are often thought of as a ‘cry for help,’ the team noted that this may not be the case at all. “Although plant volatiles may function as a ‘‘cue’’ to parasitoids, they may not be a specific ‘‘signal’’ released by the plant (implying a selective benefit),” write the authors. “It is important to emphasize that volatile cues may provide many community members with information and thereby may not necessarily result in a fitness benefit to plants.”

These findings also call into question the use of parasitoid wasps as biocontrol for managing pests. Cotesia glomarata has been introduced and intentionally released in a number of agricultural areas to control caterpillars like Pieris rapae. Recently, some have suggested that farmers might be able to spray the volatile compounds emitted by damaged plants to attract more parasitoids, as a way of reducing pest populations without using pesticides. But the authors think that this strategy might not be so clear-cut. “Our results show that hyperparasitoids may parasitize up to 55% of the parasitoid offspring, therefore potentially playing a major role in parasitoid population dynamics,” they caution. “Overexpression of herbivore-induced plant volatiles [HIPVs] in crops or field application of synthetic parasitoid attractants may not benefit pest control in conditions where the responses of hyperparasitoids to HIPVs cause major mortality to parasitoids.”

In other words, the interactions between species are far more complex than we once thought, and we can’t assume we can predict how our manipulations will affect a community—which is generally the trouble we’ve gotten into when trying to use biocontrol mechanisms. The more we try to tinker with interspecies interactions, the more unintended consequences we seem to have.

Research: Poelman E., Bruinsma M., Zhu F., Boursault A. & et al (2012). Hyperparasitoids Use Herbivore-Induced Plant Volatiles to Locate Their Parasitoid Host., PLoS Biology, 10 (11) e1001435. DOI:

Image: Nina Fatouros, www.bugsinthepicture.com

Musical Monday: As Hard As It Is

Welcome to Musical Monday, where I feature an original song just for the heck of it. Want to hear more? Check out my previous musical posts: Time – and brain chemistry – heal all wounds, Biochemically, All Is Fair, Taking Einstein’s Advice and the first Musical Monday: Stay Near Me.

So, I had a little free time this holiday weekend and re-recorded another old song of mine. This one goes way, way back to when I was in high school—and of course, it’s about a boy, as many of my songs are, and certainly many were at that age. But, it was a particularly insightful one for little 14 year old me, about how sometimes letting go is harder than it should be. Enjoy!

As Hard As It Is

    (lyrics)

Sticks and stones may break my bones, but Wild Sex excites me

We humans like to think we have the corner on kink. We bust out our whips and chains, flouting our sexual ingenuity. But, as Dr. Carin Bondar has been telling audiences for years, our sex lives are PG-13 in comparison to those in the animal kingdom. Now, she’s teamed up with producer Benjamin Hewett, director Richard Slater-Jones and award-winning wildlife documentary film company Earth Touch for new web series bluntly titled Wild Sex that bares all when it comes to the bizzarre body parts and behaviors involved when animals bump uglies.

“I have been writing and talking about animal sex for the better part of 5 years,” explains Carin, who received her PhD in Freshwater Ecology from the University of British Columbia. “We hit topics hard, and not just for the quirk factor, but because there is a lot of cool science behind so many strange mating rituals.”

When it comes to salacity, this series has it all. The show looks at the spicy sex lives of all sorts of animals, from insects to elephants, outing each for their kinkiest traits. It has your basic fetishes from bondage to orgies, prostitution, and even a little sexual cannibalism. I was fortunate enough to preview the first three episodes, and I am more than impressed with the accuracy, indecency, intelligence and humor with which Carin and her team have tackled these, uh, sticky topics. They make no apologies for the straightforward style—this is a show that gets down and dirty with nature’s deviants. “The show is all about sex, and I was not shy about it,” says Carin. “I approached it from a go big or go home standpoint. I feel like it could have come across as really drab if I played it too safe.”

And go big she does. This is no surprise to anyone who has met Carin in person. Her slogan “biologist with a twist” is spot on, and her bold yet charming personality is immediately apparent when you meet her. On screen, it is even more captivating. She has a way of drawing you right into the room with her, which, given the titillating subject matter, may be a little uncomfortable at times—in a good way. The second episode (which is about getting stuck during copulation) had me wincing and cringing throughout, yet like the soapberry bugs Carin describes, I was totally hooked. From sex toys to half-naked men, Carin wasn’t afraid to choose the right tool to get across the science—which is, of course, the show’s ultimate goal.

“I think that the person who would normally watch a science show will love it,” says Carin, “but people who would not normally watch science shows will have their attention piqued and will love watching it (and learning it!) too.” She giddily explained to me how even the actors and crew got a lot out of filming. “While we were shooting there were so many learning moments with members of the crew…people would say things like ‘Wow! I didn’t know that—that’s so interesting’. ‘I had no idea that…’ ‘I’m so glad I learned that…'”

Carin’s passion for the science behind the sex is what really makes this series work. Anyone who reads my blog knows I’m not shy about these things, but Carin’s knowledge is impressive and disarming, even for a shameless girl like me. In my interview with her, she easily made me blush. It was my fault, really. She mentioned that working with elephants was one of her favorite moments of filming, and I made the mistake of asking how they fit into a sex show. “Surely you must know about the penile clitoris?!” Actually, I don’t, but I’m looking forward to that episode, titled “You Can’t Rape An Elephant.”

Carin is well aware that not everyone will respond kindly to her bold approach to a series about animal sex. “I will (and already have) received feedback along the lines of : oh she sold out to using her looks instead of her brain, oh she’s desperate for attention, etc,” said Carin. It’s sad that any time an attractive woman talks about an even remotely racy topic, she gets these kinds of comments. But Wild Sex isn’t gratuitous; it’s an intelligent, well done scientific program that happens to be about fornication. “So yes, there is sex,” Carin says confidently. “And graphic language. And me being sexy. Take it or leave it, I stand behind my work 100%.”

I’m standing with her. This series is amazing. Carin is a smart, strong, beautiful woman with four kids who isn’t afraid to bust out of puritanical norms and discuss the darkest of animal desires with wit and sex appeal. She is the epitome of a modern feminist, unafraid of and unapologetic about being true to herself and to the science that inspires her. Besides, you have to give props to anyone who can say “detachable swimming penis”, “penis snapping” and “vaginal plugging” with a straight face.

So do yourself a favor: grab some chocolate-dipped strawberries or some oysters, light some candles, and sit down and watch Wild Sex from Earth Touch TV. I can definitely promise things will get wild, but hopefully, you’ll find your brain as aroused as other areas. Carin, Benjamin and Richard have truly nailed it—pun intended.

I only hope that I can find a way to slip in for a cameo when she films season two… What do you say, Carin? What does a girl have to do to get on an episode of Wild Sex?

…Uh, on second thought, maybe I don’t want to know.

Episode 1!

Photo of Dr. Bondar c/o Kim Mallory Photography

Advice for grad students: own it.

Recently, the always brilliant Jeremy Yoder put up a fantastic post with some unsolicited advice for getting through grad school. Then, he (on the advice of the ever-infallible Scicurious), decided to make a carnival of it: “Knowing What I Know Now”. He put out the call for everyone’s best tips. I happen to have been thinking a lot about this lately, and am more than happy to share my experiences. What follows is a mix of advice and just what happened with me, for better or worse. Hopefully it helps.

Before I get started, though, let me explain where I am in this whole process. Right now I’m still in the thick of it. I’m three and a half years into my doctorate degree, with an approved proposal and my comprehensive exams looming around the corner. So this isn’t advice from a veteran, per se—it’s advice from a fellow soldier, down in the trenches right now, still fighting the good fight. Maybe I’ll have different advice in a few years, but for now, this is what I know.

First off: don’t start until you’re ready. I remember feeling the pressure junior and senior year of undergrad. Everyone was talking about what programs were best for what, what advisors to chase or avoid, what GPA you needed to get in—it was all anyone talked about. Have you figured out what schools you’re applying to yet? Have you contacted potential advisors? What research do you think you’re going to do? The worst was one day senior year when I went to the movies, and upon presenting my student ID to get a discount, the teller said “I went to Eckerd, too! Graduated two years ago. What are you majoring in?” When I said Marine Science, she cheerfully replied “ME TOO!” It was like a punch in the stomach. It really felt like those were my options: either get into grad school somewhere, or look forward to a dazzling future selling movie tickets. The pressure was on.

Trouble was, I was still very much lost. Yes, I had research experience, but of all the things my undergraduate research project taught me, the most obvious was that I hated counting mangrove leaves. I was not the extreme field biologist that my advisors were. Similarly, while I’d dabbled in a few other research experiences through volunteering and internships, nothing felt like it fit. I liked a few things, but did I like them enough to spend the next five years doing them? To bet my career on them? As senior year came and went, I made the scariest decision of my life: I didn’t apply to grad school.

Instead, I applied to jobs. I hoped that getting a little more experience before committing myself to a degree program would help me figure out what kind of scientist I wanted to be. The little tastes of molecular biology that I had gotten in my lab courses was enough for me to think maybe, just maybe, that was the field for me. In the end, I spent two years as a research assistant studying adenosine signaling in heart cells. Guess what? The biomedical field wasn’t right for me either. But by the end of it, I figured out where I did fit. I had found my scientific niche, somewhere in between field biologist and lab lackey. When I applied to grad schools, I did so with confidence and conviction. Keep in mind that through grad school, you become the world expert on something—make sure it’s something you want to be the world expert on.

Which brings me to my second piece of advice: find your niche. I was lucky enough to be in a program that required three rotations, which means I spent my first year at UH bouncing between three very different labs. Most people in the natural sciences start with an advisor, and stay with them until dissertation do they part. That’s ok and all, but before you make that kind of lasting commitment, spend a little time and get to know the lab you’re assigning yourself to. At minimum, fly out to your prospective university, meet the man or woman in charge, and talk to their grad students. While people often joke about the similarities between grad school and marriage, there’s a lot of truth in jest. Getting a PhD in particular is a huge commitment, and you don’t want to get several years in and realize you want a divorce.

Yes, you can deal with a bad advisor or an unsupportive lab, but do you want to? Are you the kind of person with an iron will that pushes through at all costs? Some people are. Some people are tenacious, headstrong, and absolutely amazing, and they barrel through no matter how bad things get. I’m not that kind of person, which is why I’m so glad that I got those three rotations to give my potential advisors a thorough screening. Simply put, without those rotations, I wouldn’t be in the lab I am in now, and I would probably be worse off for it. My advisor is a perfect fit. He lets me be creative and come up with insane project ideas, then reels me in and pushes me to actually get things done when it’s time. His co-PI is an amazing mentor, always there with the advice, aid, or encouragement I need even though I’m not his student. And the rest of my lab: well, to put it bluntly, my lab f*cking rocks. As cliche as it might sound, they really are like family to me. Sure, we don’t all get along all the time, but when push comes to shove we have each other’s backs, and support and drive each other to be the best scientists we can be. I have no doubt that my lab mates will be my friends and colleagues for years to come. The other people I have surrounded myself with—my committee members, other graduate students and post-docs—have been my champions, drinking buddies, guides and rocks to cling to when I feel like I’m about to drown. Without the generous support I’ve received to date from my advisor, other mentors, and fellow grad students, I don’t think I would have made it this far. Honestly, I don’t think I would have made it at all. This perfect mix of camaraderie, encouragement and occasional butt-kicking was exactly what I needed.

Figure out what you need. The best way to do that is to follow your passions and instincts. Maybe the lab dynamic isn’t as important to you as having a supportive group of family nearby. Or cats. Or gardening. Find what keeps you sane and helps you keep going forward, at work and at home. Get into good, healthy routines like eating well and sleeping enough. You can break these when you need to, like when that big grant deadline approaches too quickly, but then get back into them. For me, getting a place with a real kitchen was key. I needed to cook, and when I first moved to Hawaii, all I had was a hot plate. It’s funny how something as simple as an oven can make a world of difference.

I’m not going to tell you that grad school is easy. Maybe it will be for you. Most likely, it won’t. Learn to be flexible and adapt, because things rarely go as planned. You’ll be all ready for field season, and your target species will be MIA. Your genius experiment won’t work, or you’ll spend months in the lab trying to figure out the right protocol. It’ll take an extra six months to get the permits you need. Your key piece of equipment will break. You’ll be on the verge of the discovery of a lifetime, and someone else will beat you to publication. Or, if you work where I do, your lab will get randomly shut down for construction for ambiguous and often unreliable amounts of time. These things happen to everyone, and they can feel like impenetrable walls keeping you from your degree. They’re not. You’ll find a way around them if you’re willing to bend in the right ways, ask for help when you need it, and keep your head in the game.

You’re not necessarily going to feel like you know what you’re doing all the time. Hell, I haven’t. I spent the first couple years of my dissertation wondering why anyone let me into grad school in the first place. Couldn’t they see I was far dumber than the rest of these people? Had I really tricked them all into thinking I’m good enough for this? What is going to happen when they finally figure me out, and realize that I can’t cut it?

It’s called impostor syndrome. I wish I had some magic formula for how to shake those cancerous feelings of unworthiness. I don’t. But what I do know is that over the past year, I’ve really come to own my dissertation. I’ve buckled down, focused my research, gotten things done, and crossed that hidden threshold between newbie and senior grad student. Sometime in the past six months or so, when I wasn’t looking, my impostor syndrome went into remission. If I had to guess, I would say that I finally convinced myself, through actions, that I am the scientist I kept feeling like I wasn’t. I didn’t mean to, really. It all kind of happened by accident, a side effect of really making my dissertation my own. Maybe that was the magic cure all along.

So, that’s my last and best advice to you: Be confident. Take charge. It’s your project. It’s your degree. Choose it. Love it. Own it. And guess what? You can not choose it, too. There’s no shame in deciding that grad school isn’t right for you, or that you’re in the wrong lab, program, field, career—whatever. Trust yourself to make the right call. After all, the one thing you are definitely the world expert on is you.

Tis the season of giving

Thank you to everyone who came out and donated for the annual Science Bloggers for Students Donors Choose drive – we raised $25,074 for student science programs across the country! How amazing is that? But, if you missed out on the giving, fear not – there are still plenty of ways you can hand your cash over to some worthy causes.

For those who aren’t aware, November is Movember: that special time of the year when men desecrate their pretty faces in the name of men’s health. The rules are simple: Nov 1, the guys are clean shaven. For the rest of the month, fueled by sponsors, they grow mustaches to raise money to support prostate and testicular cancer initiatives. Sadly, I know a few of these daring Mo Bros, and they could use your support! Head over to Áki’s, James’, Chris’ or David’s movember giving page to pledge for their ‘staches.

Finally, there are some great scientific projects in need of a little cash-y love on SciFund right now. Want to help support research on chemical warfare in the intertidal (with a RAP VIDEO)? How about sexy shrimp or butterfly STDs? You can be an integral part of real scientific research! There are tons of great research projects that need your help, so head on over to the SciFund page and see what tickles your fancy.

Remember, ’tis the season of giving, so open your hearts and empty your wallets!

Musical Monday: Stay Near Me

I’ve always loved music. It was my first passion—long before I was traveling the world diving for lionfish or writing up science news for Scientific American, I was writing songs. Notes and chords have always been my closest friends, the ones I turn to when I need to work something out. For some time now, I’ve been blending my original songs with science to produce the most personal posts I’ve ever written, including Time – and brain chemistry – heal all wounds, Biochemically, All Is Fair and Taking Einstein’s Advice.

Well, now I want to be more explicit in my sharing. I don’t have fancy blog posts to go with every song I’ve ever written; I’ve been writing songs since I was a kid. So, I’ve decided to start a new series: Musical Mondays. Surely I won’t manage to post one every Monday, but on some Mondays, I’ll post songs of mine to share with all of you. I’ll try and write a little backstory on the songs, just to give some perspective.

This is a song I wrote over a decade ago (gosh, has it really been that long?!), and have always played for myself when I need comfort. It’s probably the most honest and soul-searching I’ve ever been in a song, which is why I’ve kept it to myself for so many years. But talking to awesome people like David Kroll—hearing, firsthand, how much music can make an impact, even on us science types (neurologically!)—has got me thinking a lot about songwriting and what it means to me, and I think it’s time I shared more, especially the songs I guard most vehemently. So, enjoy.

Stay Near Me

    (lyrics)

Coral Recruits Goby Bodyguards Against Seaweed Assassins

Coral under siege by the seaweed Chlorodesmis fastigiata

Just below the ocean’s surface, a war is being waged. Coral reefs are under constant assault by seaweeds which seek to take control, stealing the coral’s prime sunlit location for themselves. Many of these plant invaders come equipped with deadly chemical weapons that knock down the coral’s metabolism, which might come off as an unfair fight against a seemingly unarmed foe. But corals aren’t defenseless; as a new paper in Science shows, corals have fish bodyguards at the ready to mount a defense.

Coral reefs are one of the most productive ecosystems on Earth. They’re also one of the most threatened. While managers and scientists struggle to find ways to protect these precious habitats, coral cover has decreased by 50% along the Great Barrier Reef and 80% in the Caribbean. The losses ripple up the food chain, causing declines in fisheries and ecosystem services. But not all organisms mourn coral declines—when corals struggle, seaweeds reap the benefits.

Corals and seaweeds are in a constant struggle for dominance. On healthy reefs, seaweeds are kept in check by plant-eating fishes and invertebrates which keep the algae from overtaking their coral homes. When these herbivores are lost, like when sea urchins underwent a massive die off in the Caribbean in the 1980s, the algae run rampant, reducing habitat complexity and leaving many fish homeless. Up until recently, it appeared that corals are relatively passive in this ongoing battle. But now, scientists from Georgia Tech have found that corals actively recruit defenders to fight algal invasions.

“We had been studying coral-seaweed interactions to determine which seaweeds were most damaging to which corals and the mechanisms involved,” explains study co-author and professor in the School of Biology at Georgia Tech, Mark Hay. He and his post-doc Danielle Dixson discovered that the seaweed Chlorodesmis fastigiata is particularly chemically toxic to corals, emitting lipid toxins that harm corals that they come in contact with. Yet in Fiji, where the experiment was conducted, corals seemed to be holding their own. Given the important role of herbivores, the team decided to see if the fishes living in the corals might be fighting back on behalf of their homes. So, they took Acropora nasuta colonies (an important reef-building coral) that had resident gobies and removed the fishes from some of them. They then placed algae or an algae mimic made of nylon line on the corals and watched the corals over a few days to see what happened.

The mutualistic fish Gobidon histrio in its home coral Acropora nausuta, coming out to investigate the presence of the toxic green alga Chlorodesmis fastigiata

While the fake algae (which physically covered the coral but lacked the chemical weaponry of the algae itself) had no effect, the corals where algae was transplanted were all damaged by the introduction of the competitive plant. But, the scientists noted, the corals that retained their fish residents were much better off. After three days, the amount of seaweed left on the corals was reduced by 30%, and the corals themselves suffered only 20% – 30% the damage of the corals without their fish colonies.

Assured of the important role of the fishes living in the corals, the team further investigated the interplay between the fish, coral and algae. The team introduced Chlorodesmis fastigiata to corals again, but this time they watched how the fish reacted. Within minutes, small gobies—only inches in size—emerged from their hiding places to pick at and eat the seaweed. “These little fish would come out and mow the seaweed off so it didn’t touch the coral,” said Hay.

But to really understand what was going on, the scientists took water samples from next to undamaged corals, corals damaged by algae while the algae was still present, corals damaged by algae after the algae was removed, and the algae alone away from coral. They exposed gobies to these water samples and watched how they responded. In less than 15 minutes, gobies were drawn to the water from damaged corals, but didn’t react to the chemical signature of algae by itself. “We found that the gobies were being “called to” the area damaged by the algae, and that the “call” was coming from the damaged coral, not from the seaweed.”

“This species of coral is recruiting inch-long bodyguards,” explained Hay. “This takes place very rapidly, which means it must be very important to both the coral and the fish. The coral releases a chemical and the fish respond right away.” The scientists even tested the gobies by using water from seaweed damage of a different but closely related coral species, but the fish didn’t react. “The gobies came to the rescue of their host coral but did not respond to a related coral’s chemical cues,” said Hay.

The gobies aren’t being entirely selfless. Gobies don’t just eat seaweed—they also eat mucus from the coral itself. “The fish are getting protection in a safe place to live and food from the coral,” explains Hay. “The coral gets a bodyguard in exchange for a small amount of food. It’s kind of like paying taxes in exchange for police protection.”

In addition to defending their homes, the team found that one of the little fish species gets an extra defensive boost from eating the invading seaweed. “One of the gobies was known to produce a toxic skin secretion,” explained Hay. “This goby consumed the toxic seaweed and became more toxic,” thus helping to protect it from potential predators. The other main species of goby found in the coral doesn’t have this defense, but it still fought off the attacker. “It trimmed back the seaweed from its host coral but did not consume the seaweed – it apparently just trimmed it and spit it out.”

The scientists were even able to narrow down what in the seaweed is causing the coral’s cry for help. The team took different fractions of seaweed chemicals and applied them to fake nylon mimics. Only the extract containing the known lipid chemical weapon triggered the fish defense system.

“I’m an ecologist that studies chemically-mediated interactions, but the wonderfully subtle, nuanced, and specific chemical dance being conducted here is still shocking to me,” said Hay. He noted that these findings highlight the significance of mutualistic interactions on coral reefs. “Competition among some seaweeds and corals has been important enough to drive the evolution of this wonderfully well-tuned signaling among a coral and its mutualistic fishes.” While similar mutualistic defense systems are well described in terrestrial species, this is the first time such an interaction has been shown in a marine environment.

Hay also emphasized that, at least when it comes to ecosystems, size really doesn’t matter. “Organisms need not be large or abundant to be ecologically important,” said Hay. “These tiny, inconspicuous fishes are important in slowing, or preventing, the damage that seaweeds do to corals and thus are important, but unappreciated, in stabalizing reef corals and preventing coral loss and reef decline.”

Citation: Dixson D.L. & Hay M.E. (2012). Corals Chemically Cue Mutualistic Fishes to Remove Competing Seaweeds, Science, 338 (6108) 804-807. DOI:

Photos: Coral and seaweed © Paul Asman and Jill Lenoble, under creative commons license from Gaia Guide; Goby defending coral by Danielle Dixon c/o Georgia Tech; Juvenile goby by Joao Paulo Krajewski c/o Georgia Tech