Archaeology: Stones smashed by horses can be mistaken for ancient human tools

Horses kick and stamp on rocks to keep their hooves in good shape, and archaeologists have now realised this can result in a collection of sharp stones that look like the work of an ancient human toolmaker

By Graham Lawton

Some stone tools attributed to prehistoric humans may in fact have been made by horses, according to researchers in Spain. They aren’t claiming that horses make tools deliberately, but as an accidental by-product of trimming their hooves on rocks. The discovery means that archaeologists will have to be more careful about declaring objects to be ancient human-created artefacts.

Stone tools are common in the archaeological record from about 2.6 million years ago onwards, usually consisting of small heaps of sharp-edged flakes and the cores they were chipped …