1. Hobbyist Bioengineering.

    On the heels of recent news that readily available 3­D printers and computer software can be used to manufacture firearms at home, New York Times reporter Andrew Pollack discusses another controversial cottage industry ­­ synthetic biology. The goals of the amateur group in this case appear sanguine: to produce plants that glow in the dark courtesy of an implantable gene from bioluminescent marine plants. The group already has raised money online, and is embarking on gene transplantation, the cost of which has been reduced to the hobbyist level by technological advances. Despite the allure of trees that light the street at night, two environmental organization have already petitioned the Agriculture Department to shut down the hobbyists. However, jurisdiction is unclear as, once again, the pace of scientific and technological advances is far ahead of the law.

  2. A Smelly Early Earth.

    Gunflint bacteria, first discovered in 1953, lived almost 2 billion years ago in the seas of a relatively young earth. But it wasn’t alone. New techniques for 3­D imaging of fossilized bacteria such as gunflint trapped in ancient rock have revealed that other bacteria fed on the gunflint and that process of decay probably produced a pervasive rotten­-egg stench across the planet. A byproduct of this decay would have been free carbon dioxide, which would have been released into the atmosphere, thereby providing food for photosynthesizing plants and algae. This, scientists believe, was earth’s early and very smelly cycle of life.

    More at National Geographic.

  3. Sick Salmon.

    A Canadian biologist named Alexandra Morton is at the center of a controversy over the spread of infectious salmon anemia (ISA). The disease can cause devastation among farmed salmon, and has taken its toll in Chile. Morton believes that the disease is already infecting the wild salmon populations of the Pacific Northwest. However, the scientific establishment in Canada and the United States has rebuffed Morton’s conclusion and insists that there is no convincing evidence that the disease is present in wild salmon. No doubt stoking the controversy is the long standing criticism that salmon farms tend to be overcrowded and breed diseases, such as the viral ISA, which can spread to wild salmon. Whoever is right, extra vigilance would be wise; ISA can destroy some 90% of the salmon farm population.

    More at New York Times.

  4. ‘Zoobiquity’ ­­ Another Medical Vantagepoint.

    Traditionally, human and veterinary medicine do not have many points of interconnection, and that might be a mistake according to Dr. Barbara Natterson­ Horowitz. Ten years ago, she began consulting with the Los Angeles Zoo, and that experience started her thinking about the many intersections between human and animal disease. Her book, Zoobiquity: The Astonishing Connection Between Human and Animal Health, explores some fascinating similarities and differences between human and animal disease. For example, animal studies have suggested that animals and humans are equipped with not just a flight or fight response to danger, but also a faint response, which, as every opossum knows, also can save your life.

    More at NPR’s Fresh Air.

  5. A Glass Menagerie of the Sea.

    In 1853, when the oceans were not so polluted and acidified, Leopold Blaschka, a glassmaker, became enchanted with the more delicate forms of sea life: jellyfish, anemones and octopi. He and his son began to create a unique and exquisite glass menagerie of sea creatures. In the end, they created hundreds of glass models. Writing in the New York Times, marine biologist C. Drew Harvell of Cornell University describes her efforts to locate the real-life sea creatures which inspired these glass models. Harvell’s expedition takes place in Hawaii and combines stunning underwater videography, a lost art of glass craftsmanship and the scientific quest to document how many of these once common sea creatures are still common today.

  6. The Invisible Onslaught of Feral Pigs.

    Right now in the United States, there are an estimated 6 million feral pigs. They are in almost every state, but California, Texas and Florida have the lion’s share. Wildlife News reporter Ralph Maughan discusses the many diseases that these pigs can transmit to humans, from anthrax to salmonella, and how difficult they are to control because of their impressive intelligence. They multiply quickly and their appetites and large size have put significant competitive pressure on local plant and animal populations. Public awareness, outside of hunters, seems to be limited because of scant press coverage. As Maughan puts it: “There is a lot of irony that perhaps 1500 wild wolves in the West causes a huge political stir despite effects that are hard to document, while 6­million hogs ripping up the ground is hard to get public attention.”

  7. Nectar-Loving Bats Have Specialized Tongues.

    The sugary nectar of flowers attract many admirers from bees to hummingbirds. But some species of bats have also developed a taste for sweet nectar, along with a special mechanism for getting to it. A study of one such species, Glossophaga soricina, reveals that the bat has a specialized tongue that becomes thinner and longer when a sweet smelling flower is within reach. The bat’s tongue then enlists tiny hairlike papillae that become hydraulically swollen and provide a dramatically increased surface area to the tongue in order to slurp up the flower’s nectar. The entire process takes just a fraction of a second. Honey bees and hummingbirds use different tongue structures to extract nectar, but researchers believe that the bat’s method is not unique and is probably employed in some form by other animals.

    More at Red Orbit.

  8. Dog­-Sized Dinosaurs.

    The media has fostered an automatic mental association between dinosaurs and very large animals. However, that may be only half the picture. In Canada, an 85 million­-year­-old fossil of a dog-­sized dinosaur called Acrotholus suggests that some revision is necessary. Acrotholus had a thick domed head, which not surprisingly is the only part of it that survived fossilization. David Evans of the Royal Ontario Museum believes that the world once teemed with many types of smaller dinosaurs, but that they are underrepresented in the fossil record because their smaller bones did not fossilize as well as did giant dinosaurs. Indeed, the very absence of small dinosaur fossils outside of the thick domed Acrotholus, suggests that the supposed lack of small dinosaur diversity may be illusory. Although we will likely never know what has been lost forever, Evans cautions that we ought to be careful about the conclusions we draw from what is probably a partial fossil record.

    More at The Toronto Star.

  9. A Calmer Earth Is Showing Its Age.

    Tectonic plates are separations in the earth’s crust that move slowly and sometimes collide causing earthquakes. Martin Van Kranendonk of the University of New South Wales and Christopher Kirkland of the Geological Survey of Western Australia wanted to find out the history of plate tectonics on earth. By studying rare elements in rock samples and measuring oxygen isotope levels, researchers have concluded that the earth has been tectonically active for at least 3 billion years. It those early years, the intense heat and resulting softer crust may have minimized tectonic collisions. However, the evidence suggests that the most active period for plate tectonics was 1.1 billion years ago when all of the continents collided and formed a single supercontinent. Since then, a gradual reduction of activity has occurred, as the earth ages and continues to cool internally.

    More at New Scientist.

  10. Cicadas as Barometers of Climate Change.

    This summer, the east coast will be inundated by masses of cicadas from “Brood II,” who will end their 17 year underground existence and come to the surface to breed. Although there are six other cicada groups in the United States, each tied to its own 13 or 17­ year life cycle, the insects seems to trace back to a common ancestor some 8,000 years ago. Entomologists believe that the cicadas’ separate broods formed as the result of dramatic climate warming following the last ice age. If this is the case, any new dramatic climate changes that affect the insects might be reflected in a new change in their heretofore predictable life cycles. Entomologist Craig Gibbs recently put it this way: “the cicada may yet reprise its role as climate indicator if its cycle is disrupted by a warming planet.”

    More at Scientific American.

“The Dirt: This Week in Nature” curated and written by Robert Raciti.

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