1. Oetzi’s Pedigree Fleshed Out.

    Oetzi, the 5,300 year old mummy who was found frozen mostly intact in the Alps in 1991, is the best preserved specimen of its kind ever discovered. Recently, Oetzi’s DNA has been analyzed and it is shedding some additional information about who he was. According to the analysis, Oetzi was genetically susceptible to arterial disease, a finding that corroborates physical evidence that his arteries were calcified. He was also genetically disposed to lactose intolerance, not surprising since dairy farming was relatively recent at the time. He might also have had one of the earliest cases of Lyme disease. DNA comparisons reveal that Oetzi’s remaining relatives are most likely on the islands of Corsica and Sardinia.

    Read more at New Scientist.

  2. A Small Detour in Horse Evolution.

    The Bighorn Basin of Wyoming is, and apparently always was, horse country. A multitude of horse fossils found in the soil there provide a time-line stretching over thousands of years. Scientists have now matched temperature conditions (using soil and rock samples) and the changing sizes of the skeletons of these endemic horses. The horse ancestor in question, Sifrhippus, lived in the area some 56 million years ago. It was a remarkably diminutive creature, about the size of a cat. The study of its size progression shows that as the earth warmed during a period called the Paleocene-Eocene thermal maximum, it got even smaller — decreasing in size dramatically. From an average of a strapping 12 pounds Sifrhippus pared down to about 8 and a-half pounds. The shrinking of Sifrhippus confirms a principle called Bergmann’s Rule, which predicts that mammals become smaller as the environment warms.

    Read more at New York Times.

  3. Giant Lobster’s Lucky Day.

    Maine has seen many a large lobster, but last week a record was set. The 27-pounder that was caught in Maine waters is the largest one ever recorded in the state. It was set free because the law requires that lobsters larger than 5 inches from eye to start of tail must be released. In this case, “Rocky” was the size of a three-year-old child and some 40 inches long. Impressive as this catch is, it pales in comparison to the world’s record, set in 1977, when a 44-pound lobster was caught in the waters off Nova Scotia.

    More at Global Animal.

  4. Melting Arctic Ice Means Trouble For Northern Hemisphere.

    A new study published in the Proceedings of the National Academy of Sciences predicts that the warming temperatures around the Arctic that are melting ice there will result in colder and snowier winters for the Northern Hemisphere. Although seemingly counter intuitive, the decrease in Arctic sea ice leads to changes is atmospheric circulation and enhanced evaporation, the result of which is colder than normal air temperatures and more snow below the Arctic.

    Read more at Red Orbit.

  5. Dolphin Stampede.

    Footage of an amazing dolphin “stampede” was videotaped somewhere off the California coast by tourists aboard a dolphin observation boat, Dana Pride. Thousands of dolphins are in high speed motion at the same time with spectacular effect.

    Watch the video of the “stampede”:

  6. T. rex’s Bite Fits Its Reputation.

    Scientists curious about just how powerful the bite of a Tyrannosaurus Rex might have been conducted an experiment to find out. Researchers at the University of Liverpool constructed a computer model based upon the available information on the size and structure of the T. rex’s skeletal jaw. Because the exact size of its jaw muscles is unknown, the scientists used a variety of values that represented their possible size. The result was that T. rex most likely had the most powerful bite on any predator, alive or extinct. As one researcher put it: “Our results show that the T. rex had an extremely powerful bite, making it one of the most dangerous predators to have roamed our planet. Its unique musculoskeletal system will continue to fascinate scientists for years to come.”

    Read more at Science Daily.

  7. Pollution Exposure Is Passed on Through the Generations.

    Epigenetics is a relatively new discipline. It is revealing that chemicals that affect the DNA of an organism can do so by simply turning genes on or off from outside the DNA molecule. In an experiment with rats, Michael Skinner and other scientists at Washington State University in Pullman used the infamous family of chemicals, dioxins, as well as DEET (an insecticide) and others, to determine whether chemically exposed rats would pass on the ill effects to their offspring. The results are chilling – each class of pollutants caused trans-generational reproductive defects for as many as 3 generations.

    Read more at Science News.

  8. Leaf-Nose Bat A New (Ugly) Species.

    We’ve seen ugly bats before, but this new one from Vietnam is special. On its face are bristles and leaf-like protrusions. It was first spotted in 2008, but at the time it was mistaken for a known species. Its fright is worse than its bite, however — the leaf-nose bat proved quite gentle when captured. Named Hipposideros griffini, the newest member of the bat family probably uses the projections on its face to assist in echolocation. Scientists believe that there are more undiscovered species of bats that live in the Vietnam countryside.

    Read more at National Geographic.

  9. The Big Itch — Giant Fleas From the Jurassic Era.

    About 165 million years ago, animals were larger than they are today, and so were their fleas. A flea fossil from Jurassic rock in China has been measured at 20.6 mm in length, making it many times larger than today’s fleas. Scientists speculate that these mega-fleas “may have lived on feathered dinosaurs rather than the small mammals that scuttled across the Mesozoic landscape.” Of course, the fleas were persistent and eventually found havens under the fur of mammals, where they still reside today.

    Read more at New Scientist.

  10. Heavy Metal Pollution A Threat to Wild Bees.

    While much has been written about colony collapse disorder in domesticated bees, the plight of wild bees is also getting some attention. Red Orbit reports on a study published in the Journal of Applied Ecology about how wild bees fare in heavy metal pollution areas in Great Britain and Poland. A significant mortality rate among wild bees appears to be directly correlated with high levels of toxic heavy metals. Crops such as apples tend to draw heavy metals from the soil where they are ingested by wild bee pollinators.

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

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