There's no greater thrill than spotting one of these tiny birds when on holiday, and young readers will be fascinated by how this avian machine works. Hummingbirds are the smallest birds in the world, but they exploit every advantage that comes with their modest size. 'Exploring the World of Hummingbirds' is a fully illustrated introduction to the hummingbird's high-performance lifestyle. Built for efficiency and fueled with high-energy nectar, this bird runs at a high temperature during the daytime, its heart beating 650 beats a minute, and its dense feathers keep it warm at night as it rests. Most impressive, however, are its skills as an aerial acrobat. Like a helicopter, it can move forward, backward and sideways. When feeding from a blossom, it can hover in midair and then turn and whir away at full speed - all in two-tenths of a second. Readers will find out how hummingbirds and flowers have evolved for their mutual success. They'll also discover intriguing facts about hummingbird biology, flight, mating and nesting behaviors, family life, migration, and just how a hummingbird achieves and maintains its dazzling, shimmering colors. The Exploring the World of...nature series was created for young readers who are eager to learn more about the wild creatures of the world. Each title contains beautiful photographs of the animals in their natural habitats and the highly readable text explores their daily lives and physical characteristics, how they make their homes, how they raise their young and what they eat.

The wild, wary gray wolf.

The largest wild member of the dog family, the gray wolf stalks much larger mammals, such as the elk, caribou and moose. How does it succeed? Built to run, the long-legged wolf on the hunt uses its powerful sight, hearing, smell and physical strength. But, like the domestic dog, the wolf is a social animal: it lives in a pack.

In this fully illustrated introduction, young readers will learn how group living makes sense for the wolf, allowing it to form strong bonds and share tasks like rearing its young, finding food and communicating over long distances. They'll also find out how habitat destruction, poisoning campaigns and hunting have reduced gray wolf populations in much of North America.

Full-color photographs provide close-ups and action shots, while the engaging text, sidebars and captions tell the life history of an animal that researchers agree has one of nature's most engaging personalities.

Firefly Books' Exploring the World of... nature series was created for younger readers who are eager to learn more about the wild creatures of North America. Each title contains beautiful photographs that depict the animals in their natural habitats, while the highly readable text explores their daily lives -- where and how they make their homes, what they eat, how they hunt, how they communicate and how they raise their young.