The lionfish eating their way through the Atlantic and Caribbean are among the worst marine invasive species to date. Anything we can do to limit their populations is a step in the right direction, thus it’s not surprising that some are getting creative when it comes to control. One of the most common questions I receive goes like this: What if there’s something worthwhile in their venom? Could we convince people to hunt them in droves if we can find a medical use for their spines?
It sure sounds like a perfect plan: study lionfish venom, find medically-relevant compound, and harvest millions of invasive lionfish to extract it. If only it were that simple.
Chameleons are known for their vibrant color changes. While the old wives’ tale that they change color to match their surroundings isn’t true, they are capable of remarkable shifts in hue, a trait which has fascinated scientists for years.
Now, scientists have learned from the little lizards, and have created a material that, like chameleons, can shift its colors seemingly effortlessly.
The material was created by Connie Chang-Hasnain, a professor of electrical engineering at University of California Berkeley, and her students, Li Zhu and James Ferrara, with the help of visiting student Jonas Kapraun. “One day in our group seminar we started to think about color,” Chang-Hasnain explained. “We looked at what was known at the time about how chameleon skin could change color, and we were fascinated by that, and we thought we could design for it.” And as they reveal in a study published in Optica this week, they were right. Read More
Journalists are held to the highest standards of accuracy, which is why so many seemed shellshocked to learn that Brian Williams, beloved NBC Nightly News anchor, lied about his experiences in the Iraq war. In his most recent accounts, Williams claimed to have been in a helicopter shot down by enemy fire — a claim that was vocally disputed by veterans who were with Williams at the time. Williams has since admitted that he got the story wrong, but what’s most intriguing about his apology is the seemingly-genuine level of remorse and confusion he displayed.
“I would not have chosen to make this mistake,” Williams told Stars and Stripes as a part of his retraction. “I don’t know what screwed up in my mind that caused me to conflate one aircraft with another.”
Scientists do. If we assume that Brian Williams didn’t intend to mislead, then it’s actually not that hard to explain why he’d genuinely recall something that never happened. False memories are a fairly well-known phenomenon in human memory research. Early experiments found that people readily remembered things that never existed, like a word on a given list. In more nuanced experiments since, scientists have been able to convince study participants that they were lost in a mall as a kid, had been on a hot air balloon ride, and even committed a crime. In each case, the participants really remembered the events, even though they were completely fake. So it’s not that far of a stretch to think that, after repeating the stories of riding in a helicopter and of another helicopter being hit over and over, Williams got confused and merged his two long-term memories. According to Lars Chittka, a professor of behavioral and sensory ecology at Queen Mary University of London, “It’s psychologically perfectly possible.”
Chittka’s research recently discovered that Williams is not alone: bumblebees, too, experience a similar failure of memory integrity. Read More
A long time ago, the great-great-great ancestors of humans and our relatives began to invest heavily in eyes. Sure, we have other senses — hearing, taste, touch — but primates excel at sight. There are lots of hypotheses to explain why eyesight was so evolutionarily valuable, from finding food to reading faces. But whatever the reason, vision became dominant, while other senses were left to languish, including our sense of smell. Primate olfaction is thought to be so miserable that scientists diminutively refer to our noses as “microsmatic” as opposed to the “macrosmatic” noses of dogs or rodents.
But the more we study the noses of our kin, the more we realize how important scent is to primates. Our closest cousins — the monkeys and apes in the Haplorhini (which refers to the to dryness of our noses) — possess similar sniffers to us, but as you move away from our supposedly feeble-nared lineage, our relatives become better and better smellers. Our most distant primate cousins, the lemurs and other ‘wet-nosed’ primates (Strepsirrhini), have a heightened, almost un-primate-like sense of smell, and recently, scientists have come to appreciate just how much they may rely on information obtained by their noses.
Lemurs use scents to tell who’s who, mark territories, and send important signals about their health or social status. Lemur sex lives, especially, are very smelly. Lemurs can tell whether a given secretion comes from a male or a female, and if female, whether she’s ready to make babies. Forget putting a female lemur on birth control — males will smell the difference, and lose interest.
Now, scientists have discovered that not only does smell come into play before pregnancy, lemurs emit particular scents when they’re expecting. These pregnancy odors are so unique that they can even be used to distinguish if the baby-to-be is a boy or a girl. Read More
Remember that story from last fall about the Chinese chef that died after being envenomated by the severed head of a cobra he was cooking? (Well, if not, here’s a good summary.) Many dismissed the tale outright, thinking a snake couldn’t possibly be lethal if it was no longer living. But a great photo taken this week by Lee Reeve shows just how dangerous venomous animals can be, even after death:
Lee found this wee western diamondback rattlesnake (Crotalus atrox) dead this morning. It was the runt of a recent litter, and had struggled in spite of months of assisted feeding, so Lee wasn’t surprised the little guy didn’t make it. But just because the small snake was dead didn’t mean Lee could be carefree about handling it, as he explained in a Facebook post:
“Looked like he hadn’t been dead for very long, so I took the opportunity to show why they’re dangerous, even when dead. The liquid coming from the fangs is venom, and will be just as toxic as it was when the snake was alive. Prick your finger on and the fang (or even the bottom teeth), and you got yourself an envenomation.”
Even once dead, venom that is stored in the venom gland can be injected into an unsuspecting victim if pressure is applied. And snakes, like other animals (even us!), can exhibit muscle movements post-mortem, so even if the animal isn’t alive, you can’t be sure it won’t move unpredictably. As someone who has worked for years with venomous animals, I’ve had to be careful with my study organisms even months after their demise (frozen venom can stay potent for a long time!).
So should you come across a dead snake — or anything else with venomous fangs, spines, spurs, etc — be careful! Don’t assume the dead are harmless to the living.
Any depth of understanding of biology and ecology is accompanied by this inevitable conclusion: parasites rule the world.
They’re the “man behind the curtain” as fans of Oz would put it. They are the directors and stage managers of the grand production that is life on this Earth, nature’s finest puppeteers, and that we think we have any modicum of control over any species’ physiology in comparison (including our own) is downright laughable.
The latest reminder of our inadequacy when it comes to manipulating biology comes from a fresh paper in Proceedings of the Royal Society B. In it, scientists describe how the parasitoid wasp, Dinocampus coccinellae, is able to manipulate its host, the ladybug Coleomegilla maculata: it uses another parasite, a never-before seen RNA virus.
Life as a fish larva is tough.
Your odds of survival are slim to none. First off, you can’t swim all that well, so you’re mostly-drifting around in the ocean hoping that, when it’s time for you to settle down, you find yourself somewhere suitable. You’re also really, really small — the perfect morsel for tons of other species, from jellies to krill and even other fish. And your parents? They just abandoned you, sent you and your hundreds of siblings into the harsh real world without giving you anything to help you survive.
Unless you’re a larval pufferfish, that is. Your mom and dad may not win any parenting awards, but they didn’t leave you with absolutely nothing. Your mom did something that would make other reef fish larvae incredibly jealous, and that just might save your life: she gave you poison.
Tuna are some of the most popular fishes on Earth. Globally, more than 4.3 million tonnes of tuna are caught every year, valued at more than $5.5 billion dollars. Yellowfin tuna, the species most commonly labeled as ahi in sushi restaurants nationwide, is the preferred tuna in developed nations like the US and the UK, but the world’s favorite sashimi may soon be stricken from the menu, as scientists have found that mercury levels in tuna are rising at a rate of 3.8% or more annually. More importantly, the rapid rise suggests a growing global problem that may lead to unsafe mercury levels in many fishes, even ones that are now considered completely safe. Read More
It seems like the outcry against a potential trial of genetically modified mosquitoes in the Florida Keys has become a national news topic nearly overnight. Though Oxitec has been considering the plan for years, a recent town hall received attention from the Associated Press, and BOOM — suddenly, it seems like everyone is talking about GM mozzies. As I explained in my last post, the bulk of the conversation is centered around fear of GM technology, though the fears of “mutant DNA” causing human health problems are completely baseless. But the science doesn’t seem to matter: people just don’t trust GMOs, no matter what anyone says about them. Read More
In the past few days, a new “GMO scandal” has hit the headlines. The UK biotech firm Oxitec has proposed the release of special genetically modified mosquitoes in the Florida Keys to help with current mosquito control efforts. Or, according to the media:
The Washington Post actually called them “genetically modified killer mosquitoes” in their headline, warning that they “may attack Florida Keys”. George Dvorsky for io9 cautions that “Millions Of Mutated Mosquitoes Could Be Unleashed In Florida—On Purpose”. It’s safe to say news of the FDA’s deliberations on whether to allow these “Frankenstein mosquitoes” are causing quite the stir. There’s even a Change.org petition to fight the release, with nearly 140,000 signatures.
While these mosquitoes are genetically modified, they aren’t “cross-bred with the herpes simplex virus and E. coli bacteria” (that would be an interkingdom ménage à trois!)—and no, they cannot be “used to bite people and essentially make them immune to dengue fever and chikungunya” (they aren’t carrying a vaccine!). The mosquitoes that Oxitec have designed are what scientists call “autocidal” or possess a “dominant lethal genetic system“, which is mostly fancy wording for “they die all by themselves”. The males carry inserted DNA which causes the mosquitoes to depend upon a dietary supplement that is easy to provide in the lab, but not available in nature. When the so-called mutants breed with normal females, all of the offspring require the missing dietary supplement because the suicide genes passed on from the males are genetically dominant. Thus, the offspring die before they can become adults. The idea is, if you release enough such males in an area, then the females won’t have a choice but to mate with them. That will mean there will be few to no successful offspring in the next generation, and the population is effectively controlled. Oxitec hopes to release millions of autocidal Aedes aegypti mosquitoes in the Keys because that species is a vector for deadly diseases, and Oxitec is hoping that reducing mosquito populations will protect residents. You would think that would be a good thing—but the headlines and rhetoric of the media suggest otherwise. Read More