"Today, an ancient world is vanishing right before our eyes: the age of giant animals. Over 40,000 years ago, the earth was ruled by megafauna: mammoths and mastodons, saber-toothed tigers and giant sloths. Of course, those creatures no longer exist, and there is only one likely reason for that: the evolution and arrival of the earth's only tool-wielding hunter, the wildly adaptive, comparatively pint-sized human species. Many more of the world's...

The conflict that has been simmering between the new superhumans and the Trutopians begins to boil over, threatening the world with extinction.

"Fifty shark species are at high risk of extinction, and another sixty-three are threatened. These intelligent, mysterious--and sometimes scary--fish evolved about 420 million years ago. They have adapted to survive deep in the ocean and in shallow-water habitats. Commercial fishing and finning are threatening shark populations. So is water pollution. Marine biologists and others, including young people, are working together to save these fascinating...

In 1974, when thirteen-year-old Charlie Hall's mother dies and his father retreats into silent grief, Charlie finds himself drifting, nearly friendless, through a northern Idaho junior high school but when a grizzly bear saves his life, Charlie forms an unusual friendship that changes his life.

The conflict that has been simmering between the new superhumans and the Trutopians begins to boil over, threatening the world with extinction.

Describes the life of Hannibal, the young general from Carthage who challenged the Roman empire with a powerful army in the second Punic War.