Did Neolithic switch to agriculture drive selection for lighter skin colour in Europeans?

Study finds evidence of strong positive selection for skin, eye and hair pigmentation over last 5,000 years.

Why do people living in the tropics have dark skin whereas those living in higher latitudes have lighter skin? The traditional explanation is that is an evolutionary balancing trick between protection from skin cancer on one hand and the synthesis of Vitamin D by skin cells on the other. Dark skin results from higher levels of the pigment melanin: for those living nearer the equator, higher melanin levels provides a better protection from the sun’s more intense UV radiation; conversely, for those living at latitudes where UV radiation is weaker, the protection is not required and high melanin levels would block the production of Vitamin D.
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Deep Impact?

Why an asteroid impact is unlikely to have caused the Late Quaternary mass extinction.

The Pleistocene world was dominated by large mammals, flightless birds and reptiles. These included mammoths, mastodons, giant ground sloths, camels, sabre-tooth cats, giant beavers, and giant deer with antlers spanning 3 m (10 ft.). In Australia, there lived the hippopotamus-sized Diprotodon optatum that weighed in at 2.8 tonnes, and was the largest marsupial of all time. These animals are collectively known as the megafauna, a term applied to animals with an adult weight of 45 kg (100 lb.) or more. Between 50,000 and 10,000 years ago, many of these great beasts vanished in one of the largest extinction events since the demise of the dinosaurs.
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Return from Beringia

Linguistic study suggests Ice Age groups migrated back to Central Asia from Bering land bridge.

The New World was the last habitable part of the globe to be settled by humans. Today, Alaska is separated from eastern Siberia by the Bering Strait, which is 55 km (18 miles) wide, but this has not always been the case. Throughout the period from 25,000 years ago until as late as 10,000 years ago, sea levels were so low that the strait and parts of the adjoining Chukchi and Bering Seas became dry land. The result was a landmass stretching from the Verkhoyansk Range in eastern Siberia to the Mackenzie River in northwestern Canada (Hoffecker, et al., 1993).
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Chauvet cave paintings may be far more recent than generally believed

French archaeologists claim that prehistoric artwork thought to be 36,000 years old is actually 10,000 years younger.

Chauvet Cave is located near the village of Vallon-Pont-d’Arc, Ardèche in southern France. The cave was discovered in 1994 by a team of cavers led by Jean-Marie Chauvet, for whom the site was named. It was the most important cave painting find since the discovery of Lascaux by a group of teenagers during World War II. Continue reading

Study provides insight into diet of early Pacific colonists

Lapita people relied on foraging as well as agriculture; men enjoyed a more varied diet than women.

Between 1400 and 800 BC, Polynesian colonists associated with the Lapita culture spread out into the Pacific from Island Southeast Asia, eventually settling the islands of central and eastern Melanesia and western Polynesia. The word ‘Lapita’ is a Western mispronunciation of Xapeta’a, the native Kanak name for the site in New Caledonia that gave its name to the culture. The Lapita culture is noted for its distinctive pottery, which was typically red-slipped, and decorated with small-toothed (‘dentate’) bone or shell chisels.

By around 1300 to 1200 BC, Early Lapita communities were established over a wide area of the Bismarck Archipelago. Continue reading