I have had the privilege of touring some of the French caves with these paintings, and it is a profoundly moving experience to face a wall of hand stencils that is tens of thousands of years old. From the sizes of the hands, it seems clear that a community had made them, both little children and grown adults. The marks are so incredibly old, and yet it’s easy to visualize the people holding up their hands and blowing ocher on them, leaving a shadow behind. I don’t know if it’s possible to still visit these caves today —- we were on a National Geographic tour led by paleoanthropologist Don Johanson, discoverer of “Lucy”, and he has long since retired —- but it’s well worth your time if you ever get a chance to see them.