Researchers have found new examples of the strange singled-celled creatures called xenophyophores more than six miles beneath the surface of the Pacific in the Mariana Trench. At more than four inches in length, they are perhaps the largest single-celled organism on Earth. These protists make a living by sifting through sediments and can accumulate high levels of toxic metals like uranium, lead, and mercury.
Some men just want to watch the world burn. Count me as one of them, at least when it comes to this video from NASA showing fires taking place the world over. Seventy percent of the world’s blazes take place in Africa—apparently making it the “fire continent,” according to the narrator. Perhaps surprisingly, especially given recent wildfires in the American West and Southwest, only 2 percent of the globes conflagrations take place in North America. NASA used two satellites, Terra and Aqua, to visualize patterns of vegetation, snow/ice cover, and fires worldwide from July 2002 to July 2011.
Nematode worms live longer if their grandparents had particular genes.
But they don’t need to receive the genes themselves to feel the effects.
What’s the News: Scientists have discovered that worms who’ve been given mutated genes that let them live longer pass on their longevity to their descendants—even when the descendants don’t receive the genes. How does it work?
When most people say “genetically modified organism,” they usually mean a plant—corn, perhaps, or an eggplant. But that may soon change. The FDA has completed its analysis of the first genetically modified animal likely to hit supermarket shelves: the AquAdvantage salmon, made by Massachusetts-based AquaBounty Technologies, Inc. Thanks to some added genes, the salmon grows 2-6 times the size of a normal Atlantic salmon in half the time, promising some respite for the planet’s heavily taxed natural fish stocks, a third of which are near extinction or exhaustion. Talking Points Memo’s IdeaLab reports that a source close to the review process says that the FDA’s environmental impact statement, which looks at what effect the salmon will have on the environment and seems to be favorable, has been passed on to the White House’s Office of Management and Budget.
As always with genetically modified organisms, there are questions about how the salmon’s manufacturers plan to keep its genes from getting loose in the environment. AquaBounty has developed a way to make the fish sterile, which would make spreading their genes quite tricky. At the moment, however, it only works on 98% of the salmon. Additionally, the company is only seeking approval for growing the fish in large, land-locked tanks with double-thick walls. While giant nets teeming with fish in the middle of the ocean are a sight more commonly associated with aquaculture, inland tanks make the risk of modified fish escaping much smaller.
One hopes that if the fish is approved, though, the companies building the tanks make sure to avoid floodplains. Read more at IdeaLab.
Image courtesy of AquaBounty
How did animals move from water to land? The answer may have just got a little murkier. A study published this month in the Journal of Experimental Zoology found that two distantly related fish share a similar method for jumping about on land, suggesting that a common ancestor evolved this ability long ago. But unlike amphibious fish such as the mudskipper, which has pectoral fins adapted to “walking” on land, these fish have no specialized equipment for leaping, and would therefore leave no evidence of their talent behind in the fossil record.
Hormones are major mood-regulators, as anyone who has been cranky before a period or had their reproductive organs removed for medical reasons can tell you. In fact, depression is a common side effect of such surgeries in humans. But does that extend to some of the most regularly de-hormoned animals out there—our pets? That’s the thought-provoking thesis of a recent Slate piece, and while there’s been no systematic research on how such surgeries affect cats and dogs, a smattering of research has suggested that having your supply of hormones eliminated does affect the mood of mice and primates, free of the confounding influences one finds in humans. (more…)
Israeli and German scientists recently took the plunge into the murky, salty Dead Sea, making what they say is the first scientific diving expedition there. Scouring the seafloor, they saw small freshwater springs—with mats of salt-loving, never-before-seen microorganisms coating the surface of nearby craters. In these waters—too salty for large animals, too rich in magnesium for many bacteria—seeing so much life was a surprise.
While floating in the Dead Sea is a popular tourist pastime, scuba-ing into its depths is a difficult and dangerous endeavor. Since the salty water is so buoyant, the divers had to carry 90 pounds each to weigh them down. Swallowing some of the salty water—a not-implausible occurrence during a dive—would make the larynx swell up, leading the diver to suffocate. If that weren’t enough, getting the water in your eyes would be painful at best, and potentially blinding. The scientists wore full face masks during their dive, and apparently weren’t scared off; they’re headed back down for a follow-up study in October.
What’s the News: A new analysis finds that many of the genes behind the development of modern mammalian pregnancy are controlled by mysterious genetic elements called transposons, long referred to as “junk DNA.” The results suggest that the placental uterus did not evolve gradually but instead arose from a massive, transposon-driven genetic rewiring.
Sequencing the DNA in a scoop of dirt can tell scientists what creatures are living nearby, a new study using soil from safari parks shows, and the amount of DNA present can even tell how many individuals of each species there are, which could allow field biologists to get preliminary surveys of species. But though the team managed to identify nearly all the species they had expected in the parks, from wildebeest to elephants, they are still addressing how to take samples that accurately represent the area’s biodiversity—one would have to avoid elephant latrines or wildebeest sleeping areas, for instance—and there is the additional problem that rare or small creatures, like insects, might easily be missed. That said, it’s still an unusual and interesting way to take a look at an area’s inhabitants without actually tracking them down.
A botanist has discovered a new species of plant in eastern Brazil whose branches bend down upon bearing fruit and deposit seeds on the ground, often burying them in a covering of soft soil or moss. This trick is an example of geocarpy, a rare adaptation to survival in harsh or short-lived environments with small favorable patches. The adaptation ensures seedlings germinate near their parents, helping them stay within the choice spots or microclimates in which they thrive. One well-known practitioner of geocarpy is the peanut, which also buries its fruit in the soil [PDF].
RNAs from rice can survive digestion and make their way into mammalian tissues, where they change the expression of genes.
What’s the News: It’s no secret that having lunch messes with your biochemistry. Once that sandwich hits your stomach, genes related to digestion have been activated and are causing the production of the many molecules that help break food down. But a new study suggests that the connection between your food’s biochemistry and your own may be more intimate than we thought. Tiny RNAs usually found in plants have been discovered circulating in blood, and animal studies indicate that they are directly manipulating the expression of genes.
Scientists have often wondered how woolly mammoths survived and thrived in the frigid climes of the far north in Earth’s last ice age. The hemoglobin in elephant (and human) blood cannot easily transfer oxygen to other cells in the body at low temperatures. Instead, the blood’s hemoglobin holds onto its oxygen in icy extremities and the tissue eventually dies; that’s the main reason we get frostbite. There must, then, have been something special about mammoth hemoglobin.
What’s the News: Researchers found that squalamine, a steroid present in the bodies of the dogfish shark, has a protective effect against several human viruses, all of which are difficult or impossible to cure with existing drugs. The chemical has so far been shown to be relatively safe in humans and can be synthesized, suggesting it could have promise as an antiviral drug in humans.
80beats is DISCOVER's news aggregator, weaving together the choicest tidbits from the best articles on the day's most compelling topics.
80beats is written by Veronique Greenwood and Valerie Ross. This team darts through each day's science news faster than the ruby-throated hummingbird that beats its wings 80 times per second. Send ideas, tips, suggestions, and complaints to [azeeberg at discovermagazine dot com].
Researchers have found new examples of the strange singled-celled creatures called xenophyophores more than six miles beneath the surface of the Pacific in the Mariana Trench. At more than four inches in length, they are perhaps the largest single-celled organism on Earth. These protists make a living by sifting through sediments and can accumulate high levels of toxic metals like uranium, lead, and mercury.
Parasitic wasps have a terrifying but weirdly impressive knack for taking over the bodies and brains of other many-legged creatures, making 
Fresh shark fins drying on sidewalk in Hong Kong. Credit: 
Mosquitofish can leap with “skill and purpose.”
A botanist has 
