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Polar Bears Rooted in Ireland Polar bears and brown bears were separate species by 110,000 years ago. But new genetic studies of fossils and modern bears have revealed some hanky-panky 45,000 years ago, when polar bears interbred with now-extinct Irish brown bears. Hybridization with brown bears is a concern today because declining sea ice cover is forcing polar bears to extend their range and come into contact with brown bears. To understand the implications of hybridization, Beth Shapiro, an evolutionary biologist at Pennsylvania State University, University Park, and her colleagues compared mitochondrial DNA from 8000-year-old polar bear fossils, modern samples of polar bears, and ancient Irish bear fossils. Figure "CREDIT: FOTOSEARCH (2)" Modern polar bear mitochondrial DNA was most similar to that of the extinct Irish brown bear, whereas extinct polar bears had different mitochondria. Thus modern polar bears come from Europe, not islands between Alaska and Siberia, as had been previously thought, the researchers reported in Current Biology. The finding shows that interbreeding occurred during past episodes of climate change didn't destroy a species. "The big question for conservation of polar bears is if hybridization occurs rapidly and in combination with other stressors, will that hybridization have more of a negative effect now than it did in the past," says Andrew Whiteley, a geneticist at the University of Massachusetts, Amherst. http://scim.ag/_polarbears

"Oil Exploration Oil Exploration Gulf Drilling Disaster Triggers Scrutiny of Mediterranean Oil Rush 1. Laura Margottini* A rush to find and extract oil in the Mediterranean Sea is threatening one of the planet's marine biodiversity hot spots, scientists warn. PANTELLERIA, ITALY-This tiny speck in the Mediterranean, home to a few thousand people, seems like one of the most tranquil places in the world. But looks are deceptive. Pantelleria, in the Strait of Sicily halfway between Palermo and Tunis, is close to one of the world's busiest shipping lanes, and of late, its waters have also become the center of a new oil rush. Attracted by Italy's easygoing drilling regulations and low tax on oil extraction, dozens of companies have new plans for exploration and drilling in this part of the Mediterranean Sea. At a recent meeting here,* however, scientists, conservationists, and environmental activists warned that such efforts put several important biodiversity hot spots in danger. An oil disaster like the Deepwater Horizon explosion, which sent oil gushing into the Gulf of Mexico for months, could easily ruin the Mediterranean ecology for a century or longer, some said. The Italian government has recently issued 66 permissions for drilling around its coasts and 25 concessions for exploration. Another 67 applications for exploration are under review. "Italy now represents the region that holds the most exciting and significant long-term opportunities," one company, Northern Petroleum, says on its Web site. The Strait of Sicily is the center of attention, but other biodiversity hot spots, such as the Tremiti Islands in the Adriatic Sea, could soon be explored as well. Italy isn't alone. Tunisia, for example, has granted concessions for oil exploration for most of its Mediterranean waters, without much political opposition. But the areas coveted by oil companies are ecological treasures, researchers and groups such as Greenpeace Italy stress. Last year, the Uni

A blackspot tuskfish off Australia has its mouth full as it carries a cockle to a nearby rock, against which the fish was seen repeatedly bashing the shellfish to get at the fleshy bits inside.

So, might you ask, what is the Anthropocene? First, the etymology. The Ancient Greek [anthropos] means "human being" while [kainos] means "new, current." The Anthropocene would thus be best defined as the new human-dominated period of the Earth's history. The term was proposed in 2000 by Paul J. Crutzen, Nobel Prize in 1995 for his work on atmospheric chemistry and his research on stratospheric ozone depletion (the so-called "hole"), and by Eugene F. Stoermer in a publication (p. 17) of the International Geosphere-Biosphere Programme. But the concept itself, the idea that human activity affects the Earth to the point where it can cross a new age, is not new and dates back to the late nineteenth century. Different terms were proposed over the decades, such as Anthropozoic (Stoppani, 1873), Noosphere (de Chardin, 1922; Vernadsky, 1936), Eremozoic (Wilson, 1992), and Anthrocene (Revkin, 1992). It seems that the success of the term chosen by Crutzen and Stoermer is due to the luck of having been made at the appropriate time, when humankind became more than ever aware of the extent of its impact on global environment. It should be noted that Edward O. Wilson (who suggested Eremozoic, "the age of loneliness") popularized the terms "biodiversity" and "biophilia." Technically, the Anthropocene is the most recent period of the Quaternary, succeding to the Holocene. The Quaternary is a period of the Earth's history characterized by numerous and cyclical glaciations, starting 2,588,000 years ago (2.588 Ma). The Quaternary is divided into three epochs: the Pleistocene, the Holocene, and now the Anthropocene.

"Will Deepwater Horizon Set a New Standard for Catastrophe? 1. Richard Kerr, 2. Eli Kintisch and 3. Erik Stokstad Summary The fiery destruction of an oil drilling platform in the Gulf of Mexico on 20 April may have triggered one of the worst environmental disasters in U.S. history. The impact of the crisis, which began with the deaths of 11 workers and then simmered for several days before an expanding oil slick grabbed worldwide attention, promises to test the federal government's ability to protect habitat, wildlife, and the economic well-being of a four-state region on a scale never before imagined. "

"A horrendous slaughter is going on out here," said Peter D. Ward, a biologist from the University of Washington, during a recent census of the marine creature in the Philippines. "They're nearly wiped out." The culprit? Growing sales of jewelry and ornaments derived from the lustrous shell. To satisfy the worldwide demand, fishermen have been killing the nautilus by the millions, scientists fear. Now marine biologists have begun to assess the status of its populations and to consider whether it should be listed as an endangered species to curb the shell trade.

Deceptive marketing may help. The iridescent material inside nautilus shells is sometimes machined into pleasing shapes and sold as "Osmeña pearl." (In the Philippines - home to much nautilus fishing - the Osmeña family is a political dynasty, and its name lends cachet.)