"It is time for T. rex and his dinosaur cousins to step aside and let other mega-predators like the terror bird and the giant ripper lizard take the spotlight! Travel back to prehistoric times and meet some of the most impressive creatures to ever roam the Earth. You'll be amazed at the size and the fierceness of these lesser-known predators, many of them ancient ancestors of animals that we still see today. Stewart's cheeky, humorous voice -- along...

Estivation is just like hibernation - only it happens in summer instead of winter. Why do some animals settle into cool, snug spots and sink into a summertime sleep? Because it's too hot for their bodies to function, or their food is in short supply. Some estivating animals sleep groups; others rest alone. Some go on a long journey before they slumber; others hunker down right at home. From the pixie frog to the spotted turtle to the desert hedgehog,...