Thirty thousand years in the making and 31 years in the writing, Auel's overlong and underplotted sixth and final volume in the Earth's Children series (The Clan of the Cave Bear; etc.) finds Cro-Magnon Ayla; her mate, Jondalar; and their infant daughter, Jonayla, settling in with the clan of the Ninth Cave of the Zelandonaii. Animal whisperer and medicine woman Ayla is an acolyte in training to become a full-fledged Zelandoni (shaman) of the clan, but all is not rosy in this Ice Age setting; there are wild animals to face and earthquakes to survive, as well as a hunter named Balderan, who has targeted Ayla for death, and a potential cave-wrecker named Marona. While gazing on an elaborate cave painting (presumably, the Lascaux caverns in France), Ayla has an epiphany and invents the...