Toner
09-08-2008, 04:40 PM
Last mammoths came from North America
ANNE MCILROY
Globe and Mail Update
September 4, 2008 at 12:32 PM EDT
An international team of researchers has discovered that the last of the woolly mammoths were from the Yukon and Alaska.
McMaster University molecular evolutionary geneticist Hendrik Poinar and his colleagues analyzed the DNA from the remains of 160 of the ice-age mammals found in the Yukon, Alaska and Siberia.
They identified two groups so distinct they might have been separate species – Siberian mammoths, which died out first, and North American mammoths, which moved over the land bridge to colonize what is now Russian territory.
This suggests that the final survivors, which died 3,700 years ago in Siberia, were descendents of the North American migrants, Dr. Poinar said.
http://images.theglobeandmail.com/archives/RTGAM/images/20080904/wmammoth0904/0905mammoth400big.jpg
He and his colleagues published their results in the latest edition of the journal Current Biology, and said they were surprised by what the DNA analysis revealed. Many mammoth researchers have seen the North American animals as a sideshow with no particular importance to the evolution of the species.
”We never expected that there might have been a complete overturn in woolly mammoths,'' said Ross MacPhee, a curator at the American Museum of Natural History in New York City and one of the authors of the paper.
The work adds a layer of complexity to the already difficult scientific challenge of figuring out why mammoths became extinct. Most disappeared roughly 10,000 years ago, although a few island populations in Siberia hung on much longer.
This discovery suggests that the original Siberian animals got into trouble much earlier, and disappeared about 40,000 years ago.
Meanwhile, a boom was under way in North America, and many animals crossed the land bridge across the Bering Strait, Dr. Poinar said.
But the scientists do not understand why the migrants from the Yukon and Alaska prospered while the Siberians disappeared, or what caused the demise of the North American mammoths so many years later.
http://www.theglobeandmail.com/servlet/story/RTGAM.20080904.wmammoth0904/BNStory/Science/home
ANNE MCILROY
Globe and Mail Update
September 4, 2008 at 12:32 PM EDT
An international team of researchers has discovered that the last of the woolly mammoths were from the Yukon and Alaska.
McMaster University molecular evolutionary geneticist Hendrik Poinar and his colleagues analyzed the DNA from the remains of 160 of the ice-age mammals found in the Yukon, Alaska and Siberia.
They identified two groups so distinct they might have been separate species – Siberian mammoths, which died out first, and North American mammoths, which moved over the land bridge to colonize what is now Russian territory.
This suggests that the final survivors, which died 3,700 years ago in Siberia, were descendents of the North American migrants, Dr. Poinar said.
http://images.theglobeandmail.com/archives/RTGAM/images/20080904/wmammoth0904/0905mammoth400big.jpg
He and his colleagues published their results in the latest edition of the journal Current Biology, and said they were surprised by what the DNA analysis revealed. Many mammoth researchers have seen the North American animals as a sideshow with no particular importance to the evolution of the species.
”We never expected that there might have been a complete overturn in woolly mammoths,'' said Ross MacPhee, a curator at the American Museum of Natural History in New York City and one of the authors of the paper.
The work adds a layer of complexity to the already difficult scientific challenge of figuring out why mammoths became extinct. Most disappeared roughly 10,000 years ago, although a few island populations in Siberia hung on much longer.
This discovery suggests that the original Siberian animals got into trouble much earlier, and disappeared about 40,000 years ago.
Meanwhile, a boom was under way in North America, and many animals crossed the land bridge across the Bering Strait, Dr. Poinar said.
But the scientists do not understand why the migrants from the Yukon and Alaska prospered while the Siberians disappeared, or what caused the demise of the North American mammoths so many years later.
http://www.theglobeandmail.com/servlet/story/RTGAM.20080904.wmammoth0904/BNStory/Science/home