Sleep tight
How do people in polar regions, where there can be up to 24 hours of daylight or night, cope physiologically?
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Underground line
On a March visit to the North Carolina seashore, I encountered this tableau (see photo) of two types of markings on an otherwise pristine sand dune. One of them seems to be a trail left in the surface by a passing arthropod. The other has a mound-like relief and it appears to have been made by the sand being pushed upwards from below. The mounds' height and width are generally uniform along their length, at perhaps 1 and 1.5 centimetres, respectively; there are branches at several points; and nowhere do there seem to be openings to the surface. Does anyone have an explanation?
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Sound effects
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Silver surfers
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Blood sausage
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Hamsterverse
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