How Wasps (And Their Nests) Help Date Ancient Painting

A nest built on top of a painting is probably younger than the painting,but a nest covered over with pigment is probably older than thepainting. At one site, ancient people had painted a figure over theremains of one nest, and some time later, wasps built two more mud nestsatop the painting. Radiocarbon dating those nests suggested that thepainting is 11,300 to 13,000 years old. – Ars Technica