sciencehabit (1205606) writes "Most preschoolers get scolded for writing on walls, but kids living 13,000 years ago were encouraged to scribble, at least in caves. Among the prolific paintings and other art in the 8 kilometer-long Rouffignac cave system in southwestern France are a number of unusual markings known as finger flutings, which are made by people dragging their hands through the soft silt that lines the cave's walls. By analyzing the finger flutings of modern humans, researchers discovered that the ratio of the distance between the three middle fingers indicate that many of the cave artists were very young children, one as young as 2 or 3 years old. The researchers were also able to tell the children's genders from the shape of the fingers."
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