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When the Vikings set sail for the British Isles they had small, furry stowaways aboard their ships, and researchers say that the descendants of those mice can offer clues about the voyages taken by Viking seafarers. A new study examined the DNA of house mice throughout the British Isles and found that mice from areas where the Vikings are thought to have settled are genetically distinct from mice in other regions.

Says study coauthor Cath Jones: “We have found that most of the mice in the north of Scotland – from Orkney, Shetland and Caithness – are all of one very similar type that we have named the Orkney lineage and they are very similar to Norwegian mice. And the only explanation for that is that when the Vikings came raping and pillaging to Scotland they took their house mice with them” [Scotsman].

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For the first time, scientists have sequenced the mitochondrial DNA of a Neanderthal. Researchers at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed the genetic material from a 38,000-year-old leg bone found in Croatia and published their findings today in Cell.

The mitochondria are only passed down the female line, so can be used to trace the species back to an ancestral “Eve”, the mother of all Neanderthals. The team analysed the DNA of 13 genes from the Neanderthal mitochondria and found they were distinctly different to modern humans, suggesting Neanderthals never, or rarely, interbred with early humans. The genetic material shows that a Neanderthal “Eve” lived around 660,000 years ago, when the species last shared a common ancestor with humans [Guardian].

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Cro-Magnon people and Neanderthals may have shared their European habitat from 45,000 to 30,000 years ago, but new evidence suggests that they didn’t get more intimate than that. Italian researchers sequenced mitochondrial DNA from Cro-Magnon bones dating from 28,000 years ago and found no trace of Neanderthal DNA, suggesting that the two early hominids did not interbreed to create modern humans.

The fate of the Neanderthals, who vanish from the fossil record around 30,000 years ago, has been fiercely debated. One theory, known as the Out of Africa hypothesis, holds that modern humans, whose ancestors had recently migrated from Africa, drove the Neandertals extinct, possibly through warfare, disease, or cognitive advantage. But the competing multiregional hypothesis argues that Neandertals and modern humans interbred and that Neandertals were absorbed into our gene pool [ScienceNow Daily News].

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A clump of hair that lay frozen in the Greenland tundra for 4,000 years has yielded DNA from the earliest Arctic residents, and offers clues to their origins.

Researchers have long wondered who those rugged settlers were, and where they came from. Were they part of a massive migration that swept through all of North America, or were they a separate tribe that eventually gave rise to Greenland’s present-day Eskimos?

Until now, no ancient human remains had been found in that harsh climate to allow researchers to study the genetics of those “Paleo-Eskimos.” But the new discovery sheds some light on the people, and suggests that neither of the earlier theories is correct; in fact, they were a distinct tribe that journeyed all the way from Siberia to Greenland, but didn’t stick around to populate the frozen north.

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