Levy, a California freelance with an interest in wildlife ecology, asserts that to save the elephant, lion, grizzly bear, and other megafauna we must first understand the mastodon. Scientists have long debated whether prehistoric people drove large ice age animals to extinction. Now, delving into the private lives of these long-gone giants, strong parallels are being uncovered between their fate and the plight of modern wildlife; and scientists suggest it may be possible to manage these large animals in ways that will help restore wild habitats. For example, bringing elephants and cheetahs to the Great Plains as stand-ins for their extinct native brethren. Critics, including biologists enmeshed in the struggle to restore native species like the gray wolf and the bison, see the proposal as a dangerous distraction from more realistic and legitimate conservation efforts. Deftly navigating competing theories and emerging evidence, Once and Future Giants examines the extent of human influence on megafauna extinctions and explores innovative conservation efforts around the globe.