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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

"Penguin feathers are highly modified in form and function, but there have been no fossils to inform their evolution. A giant penguin with feathers was recovered from the late Eocene (~36 million years ago) of Peru. The fossil reveals that key feathering features, including undifferentiated primary wing feathers and broad body contour feather shafts, evolved early in the penguin lineage. Analyses of fossilized color-imparting melanosomes reveal that their dimensions were similar to those of non-penguin avian taxa and that the feathering may have been predominantly gray and reddish-brown. In contrast, the dark black-brown color of extant penguin feathers is generated by large, ellipsoidal melanosomes previously unknown for birds. The nanostructure of penguin feathers was thus modified after earlier macrostructural modifications of feather shape linked to aquatic flight. "

"Washington, DC - 03/12/2012 - The Pew Environment Group commended Sens. John Kerry (D-Mass.), Olympia J. Snowe (R-ME), John D. Rockefeller (D-WV), Scott Brown (R-MA), and Sheldon Whitehouse (D-RI) today for introducing the Fisheries Investment and Regulatory Relief Act (FIRRA). A companion bill is expected in the House by Reps. Barney Frank (D-MA) and Frank Guinta (R-NH). This bipartisan legislation would ensure that key programs critical to sustainably managing ocean fish populations, and the fishermen and communities that depend on them, would receive increased and sustained funding. "