terça-feira, 4 de junho de 2013

Mamute preservado por 15 mil anos

Russians Recover Fresh Flowing Mammoth Blood



About 15,000 years ago, an old female wooly mammoth plunged through the ice as she was being chased by predators. Her remains have now been uncovered by scientists working in Siberia. And remarkably, as they were digging it out, blood began to stream out - wich is weird given that it was 10° below freezing.
It’s not known if the blood or tissue samples contain living cells required for cloning. And even if such cells are recovered, the DNA repair would require a very complex process that could take years. A report is expected later this July.
The beautifully preserved specimen was discovered partially embedded in a chunk of ice at an excavation on the Lyakhovsky Island, the southernmost group of the New Siberian Islands in the Arctic seas of northeastern Russia.
The mammoth’s lower portions, including the stomach, were locked in the ice for the past 10,000 to 15,000 years. Its lower jaw and tongue were also recovered; the trunk was found separately from the carcass. The upper torso and two legs were preserved in soil and show signs of being gnawed upon by both prehistoric and modern predators.
Semyon Grigoriev, head of the Museum of Mammoths of the Institute of Applied Ecology of the North at the North Eastern Federal University, is calling it “the best preserved mammoth in the history of paleontology.”
During the excavation, and as the researchers were chipping away at the ice, they noticed splotches of dark blood in the ice cavities below the mammoth’s belly. When they broke through with a poll pick, blood started to flow out.
“It can be assumed that the blood of mammoths had some cryo-protective properties,” noted Grigoriev. Mammoth blood, it would appear, contains a kind of anti-freeze. This is consistent with work done by Canadian geneticists who in 2010 showed that mammoth hemoglobin releases its oxygen much more readily at cold temperatures than that of modern elephants.
In addition to the blood, the paleontologists also recovered well-preserved muscle tissue. The scientists say it has a natural red color of fresh meat. The blood is currently undergoing a bacteriological analysis, and the results are expected soon.
Based on the preliminary evidence, the scientists say the female wooly mammoth was anywhere from 50 to 60 years old and weighed about three tons. They theorize that she was trying to escape from predators when she fell through the ice, or that she got bogged down in a swamp.