Original sentence: Nearly 400 caves have now been discovered in France and Asia that contain art from prehistoric times.The earliest known European cave paintings date to Aurignacian, some 17,000 years ago.When Marcelino Sanz de Sautuola first encountered the Magdalenian paintings of the Altamira cave, Cantabria, Spain in 1878, the academics of the time considered them hoaxes
Edited sentence: Nearly 350 caves have now been discovered in France and Spain that contain art from prehistoric times.The earliest known European cave paintings date to Aurignacian, some 32,000 years ago.When Marcelino Sanz de Sautuola first encountered the Magdalenian paintings of the Altamira cave, Cantabria, Spain in 1879, the academics of the time considered them hoaxes