A study into the mysterious changing skull shape of medieval man casts serious doubt on current theories.

The peculiar shift from long narrow heads to those of a rounder shape, and back again, which took place between the 11th and 13th centuries, has been noted at sites throughout western Europe. But a study of skulls found at the deserted village of Wharram Percy, near Malton, North Yorkshire, suggests that the anatomical blip was not down to an influx of Norman immigrants, or climate change, English Heritage has said.

It examined nearly 700 skeletons recovered from the village. Unlike other research, data from the Wharram site traces the change to a single, indigenous community which has been radiocarbon-dated.

Simon Mays, a skeletal biologist, said: “Our work has yielded few clues on why skulls changed, but we have cast serious doubt on some of the current theories. Despite the best efforts of science, we’re still in the dark to explain why it happened.”

The findings are presented in the latest volume of the Wharram Percy project, which aims to publish the results of 40 years of archaeological excavations at the Yorkshire Wolds village between 1950 and 1990.

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