Why the missing fingers? Henri COSQUER/Gamma-Rapho via Getty

Stone Age Europeans may have deliberately amputated their fingers during religious ceremonies. The controversial idea could explain why so many of the prehistoric images of hands on cave walls are missing fingers.

“Finger amputation was a reasonably common behaviour in many regions in the recent past,” says Mark Collard of Simon Fraser University in British Columbia, Canada. “The available data seem to fit reasonably well with the hypothesis that some Upper Palaeolithic people engaged in finger amputation for the purposes of religious sacrifice.”

Images of hands, whether handprints or hand stencils, …