A new study in Nature Geoscience suggests that an asteroid strike may not only account for the demise of ocean and land life 65 million years ago; the resulting dust, darkness and toxic metal contamination may also explain the geographic unevenness of extinctions and recovery.

Using 823 samples from 17 drilling sites in both the Northern and Southern Hemispheres, researchers analyzed the community structure of calcareous nannoplankton. Included in their study were two sites -- one in the Pacific and one in the South Atlantic -- with reliable, accurate dating.

The longer an individual uses marijuana, the more likely that person is to meet criteria for psychosis, according to a report to appear in the May print issue of the Archives of General Psychiatry. Previous studies have identified an association between cannabis use and psychosis, but the authors of the current study say concerns remain that earlier research has not adequately accounted for confounding variables.

Geologists at the Woods Hole Oceanographic Institution (WHOI) say the massive, 8.8-magnitude earthquake that struck Chile last week occurred in an offshore zone that was under increased stress caused by a 1960 magnitude 9.5 earthquake.

 Some 300-500 times more powerful than the magnitude 7.0 quake in Haiti Jan. 12,  the earthquake ruptured at the boundary between the Nazca and South American tectonic plates. The temblor was triggered when the "subducting" Nazca plate was thrust under the South American plate, uplifting a large patch of the seafloor and prompting tsunami warnings throughout the Pacific Ocean. The two plates are converging at a rate of 80 mm per year, says WHOI geologist Jian Lin, "which is one of the fastest rates on Earth."

Researchers analyzing mitochondrial DNA extracted from a polar bear fossil discovered in Norway in 2004 say the species is relatively young, splitting off from brown bears approximately 150,000 years ago and rapidly evolving during the late Pleistocene. The findings are published in the Proceedings of The National Academy of Sciences

"Very few polar bear fossils have been found, leading to widely varying estimates of exactly when and how polar bears evolved," explains Øystein Wiig, polar bear expert and co-author at the University of Oslo's Natural History Museum. "Because polar bears live on the ice, their dead remains fall to the bottom of the ocean or get scavenged. They don't get deposited in the sediments like other mammals."

Climate Change Debate Ends In Global Accord


I would so love to see that headline for real; wouldn't you?


I can just imagine some of the big names on both sides of the debate coming together for a meeting in a Berlin beer cellar, perhaps the famous Kuhfurz Klimakeller.  After a few beers, a heated debate and a modicum of fisticuffs they conclude their cordial get-together with a joint news release.  The news release spells out the scientific points on which both sides are agreed.  It is issued at 03:00 am local time.  It is picked up rapidly by the British hapless haploid tabloids and misreported at 05:00 gmt to an eagerly awaiting world:

MEDIEVAL MEDICINE