The final question ( What do the dots represent? ) came to Lena in a dream. She woke up and counted: thirteen dots. The lunar cycles from one solstice to the next. The horse, she realized, was not a horse. It was a symbol of movement, of the herd that follows the seasons. The red hand was a shaman saying: I mark this time. I control this journey.

(was previously used for other purposes) – Uranium-series dating was already a known technique, but its application to cave art was the new development.

Dr. Pike dates the paintings themselves, not just artifacts on the ground.