With a contemplative tone, the author (In the Shadow of the Sabertooth, 2013) reflects on solo trips as well as adventures with his friends and family. Peacock's descriptions--whether of exploring the ranges and valleys of the Sonoran Desert, floating and fishing in a river in Montana, or studying grizzlies in Yellowstone and tigers in Siberia--are detailed and vivid, immersing the reader in the experience. Glimpses of his personal life, from preparing...

For the past 12,000 years, the earth has experienced a relatively stable climate. Today, that predictability has ended, and global warming is our new reality. Yet such shifting weather patterns threatened Homo sapiens once before, right here in North America as the continent was first being colonized. About 15,000 years ago, the weather began to warm, melting the glaciers of the Late Pleistocene and driving the beasts of the Ice Age toward extinction....