Archaeologist Dean Snow of Pennsylvania State University studied the handprints found across eight different historic cave sites in France and Spain, the most famous ranging from about 12,000 to 40,000 years old. After paying closer attention to the finger lengths of handprints, he found that contrary to popular belief, most of these markings were created by women.

Based on the findings of British biologist John Manning, women’s ring and index fingers are generally about the same length, while men’s ring fingers tend to be slightly longer than their index fingers.

Measurements suggest that about three-quarters of the handprints were left by women. (Images: Wikimedia/Dean Snow)