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6.17 Sleeping and Napping
Could midday napping save your life? If the experience of Greek men is any guide, the answer just may be yes.
In a study released yesterday, researchers at the Harvard School of Public Health and in Athens reported that Greeks who took regular 30-minute napping were 37% less likely to die of heart disease over a six-year period than those who never napped. The scientists tracked more than 23,000 adults, finding that the benefits of napping were most pronounced for working men.
Researchers have long recognized that Mediterranean adults die of heart disease at a rate lower than Americans and Northern Europeans. Diets rich in olive oil and other heart-healthy foods have received some of the credit, but scientists have been intrigued by the potential role of napping.
The study concluded that napping was more likely than diet or physical activity to lower the incidence of heart attacks and other like-ending heart ailments.
Specialists not involved with the study said there are sound biochemical reasons to believe that a nap may help protect against heart disease. Essentially, they said, sleep at any time of day acts like a value to release the stress of everyday life.
According to new research, house mice (Mus musculus) are ideal biomarkers of human settlement as they tend to stow away in crates or on ships that end up going where people go.
Using mice as a proxy for human movement can add to what is already known through archaeological data and answer important questions in areas where there is a lack of artifacts, Searle said.
Where people go, so do mice, often stowing away in carts of hay or on ships. Despite a natural range of just 100 meters (109 yards) and an evolutionary base near Pakistan, the house mouse has managed to colonize every continent, which makes it a useful tool for researchers like Searle.
Previous research conducted by Searle at the University of York supported the theory that Australian mice originated in the British Isles and probably came over with convicts shipped there to colonize the continent in the late 18th and 19th centuries. In the Viking study, he and his fellow researchers in Iceland, Denmark and Sweden took it a step further, using ancient mouse DNA collected from archaeological sites dating from the 10th to 12th centuries, as well as modern mice.
He is hoping to do just that in his next project, which involves tracking the migration of mice and other species, including plants, across the Indian Ocean, from South Asia to East Africa.