Western Europe's massive prehistoric tombs were built in a burst of activity over a few centuries around 4000 BC, suggests dating evidence, rather than continuously throughout the Stone Age.

In the current European Journal of Archaeology, archaeologist Chris Scarre of the United Kingdom's Durham University, looks at the latest dating of "megalithic" prehistoric tombs stretching from Sweden to Spain. The mound-shaped burial sites are better known as "barrows" in Great Britain, or "passage tombs" for their intersecting halls of corbel stones.

"It trivializes the tombs to call it a fad, but building such structures seems to have become a fashion where great numbers were built and then there was a cessation for centuries," Scarre says, in an interview. Improved dating of materials such as birch bark, bone and stone left in the tombs now reveals the clustered construction times of the mounds, he says.

Rather than a single "megalithic" culture stretching across Europe, the outburst of mound tombs likely represents an idea reaching local cultures, he suggests, which then "stopped and started" across the centuries. "One big implication is the realization that the people buried in this fashion represent only a small fraction of the people who were alive then," Scarre says. "Until the Roman era, thoughtful burial of the dead may have been a rare thing in this part of Europe."

By Dan Vergano