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The Dirt: This Week in Nature (December 1-7)

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  1. Birds Put Cigarette Butts to Good Use.

    Urban birds have been known to use discarded cigarette butts to line their nests. It makes sense since those butts are ubiquitous, soft and easily transported. However, it now appears that they confer a more important benefit than just a cheap building material. Researchers decided to examine nests in which cigarette butts were being utilized. They found that the number of parasitic mites in those nest were significantly lower than in nests without the butts. Chalk up another one for the lethal effects of cigarettes.

    More at Scientific American.

    Photo by Flickr user msSeason via Creative Commons.

    Photo by Flickr user msSeason via Creative Commons.

  2. Volcano Instantly Baked A Rhinoceros.

    Around 9 million years ago a rhinoceros was more than likely minding its own business as it wandered through what in now Turkey. Unfortunately for the rhinoceros, but luckily for paleontologists, it was in the path of a volcanic eruption and was instantly baked by ash at a temperature exceeding 800° F. The preserved fossil is an extreme rarity for science since only 2% of fossils are found in volcanic ash and very few of those are of mammals. The animal appears to be related to the contemporary African white rhinoceros.

    More at National Geographic.

  3. First Real Photographs of DNA Molecules.

    DNA, the stuff of life, has been indirectly imaged before but never actually photographed. Using a new technique that involves silicon pillars around which the DNA molecules can be artificially wrapped, Italian scientist Enzo di Fabrizio of the Italian Institute of Technology in Genoa, Italy, has managed to take actual electron microscope images of DNA. The images show the expected corkscrew shape of the molecule. In order to allow the molecule to survive the energy of the electron microscope, what is being imaged is actually six molecules wrapped around a seventh. Nonetheless, the team expects to be able to differentiate individual DNA molecules in the near future using lower-energy electrons.

    More at New Scientist.

  4. Graceful Giant Pirouettes To Feed.

    The blue whale is the world’s largest predator at 100 feet long and over 300,000 pounds, and it feeds almost exclusively on the tiniest of prey — krill. But while other smaller whales do a semicircle in the water while feeding, the blue whale is able to execute a 360° roll while eating krill. Somehow, the full pirouette allows the blue whale to more efficiently capture the tiny krill when it opens its mouth. Exactly how the blue whale is able to so precisely orient its large body to trap the krill is still a mystery.

    More at Discovery.

  5. How Dogs Shake Off Water.

    Ever wonder how your dog can so efficiently shake herself dry? Georgia Institute of Technology researchers in Atlanta wondered too, and so they did some experiments to find out. In all fairness, many hairy animals besides dogs are able to efficiently shake themselves dry. It turns out that the size of the animal is key to determining the right frequency for the shake. According to Science News, “The researchers found that the bigger an animal gets, the slower it shakes. Whereas a mouse shakes off water with a frequency of 27 hertz, meaning it shakes back and forth 27 times a second, a grizzly bear does it at 4 hertz.” The researchers found that by using just the right frequency of gyrations for their size, animals were able to whisk away an optimal amount of water to get dry fast.

  6. Zombie Genes.

    In this week’s New York Time Science section, the focus is on how parasites take control over their host’s nervous systems. It is well known that parasites can alter the behavior of their hosts in order to make it do the parasite’s bidding. Now science is focusing on just how the genetic machinery of the host is hijacked. For example, a minute parasitic wasp can infect a spider and cause it to spin a strange new web that is specifically designed for the wasp larvae inside the spider, not the doomed zombified spider. In another example, a virus that infects caterpillars has a gene that overrides the caterpillar’s genetic instructions, causes it to climb high into a tree, and then destroys the caterpillar, raining down more viruses on new potential zombie caterpillars. Unlike modern pharmacology, which can manage the manipulation of only one of two brain chemicals, parasites have evolved a virtual boatload of genetic tweaks that affect many brain chemicals of the hosts simultaneously. Perhaps, someday, parasites will teach us how to better manage mental disorders.

  7. Microchimeric Cells and Motherhood.

    No one would argue that motherhood is a gift of life, but it appears that children leave behind more than just bloat once they are born. Microchimeric cells are cells from the fetus that are left over and live in the mother’s body after childbirth. In some cases, these cells may be transferred via the placenta or, possibly, through breast feeding. They can reside anywhere in the body and have even been reported to survive in the brains of mothers for decades after giving birth. These “foreign” cells have been associated with autoimmune diseases and multiple sclerosis in the mothers. But they can also be beneficial. Although research into the issue is still in the early stages, fetal microchimeric cells in the brain seem to be associated with a lower incidence of Alzheimer’s disease. They may also protect against cancer since they are partly the mother’s genes and therefore heighten the immune system’s sensitivity to mutated lookalike cells that are the hallmarks of cancer cells.

    More at Scientific American.

  8. Mountain Gorilla Population Increases.

    A census conducted by the Wildlife Conservation Society shows that the world’s mountain gorilla population now stands at around 800 — a 100 individual increase since 2006. The good news is largely the result of continued cooperation between Uganda, Rwanda and the Democratic Republic of Congo in enhanced enforcement of anti-poaching laws in Uganda’s Bwindi Impenetrable National Park. There remain only two populations of mountain gorillas, those in the Bwindi Park and another population to the south in the Virunga Volcano area.

    More at Discovery.

  9. Extroverted Primates Live Longer.

    Psychological studies show that happy, extroverted humans tend to live longer than their introverted peers. Perhaps then it should come as no surprise that extroverted gorillas also seems to live longer than shy ones. The study of gorillas in captivity was conducted by Alex Weiss of the University of Edinburgh. The effect is not age or gender related. Of course, assessing gorilla personality has to take into account that it is humans, not gorillas, who are interpreting gorilla behavior. Moreover, factors naturally associated with an outgoing good nature, such as good overall health, are intertwined with extroversion and are not easily separated.

    More at Live Science.

  10. Egyptian Puppy Mummies.

    For reasons still unknown, ancient Egyptians appear to have mummified literally millions of animal remains, many of them puppies. The mummifications were not carefully done and the littering of the fossils, which are some 2,500 years old, is apparently chaotic. These so-called “Dog Catacombs” were first discovered over 100 years ago but the true extent of the tunnels that house these puppy mummies is only now being realized.

    More at National Geographic.

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

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