<p> Dinosaurs have been dead for millions of years and yet, we\'re learning new things about them almost every day. That\'s the theme of the BBC documentary series “Planet Dinosaur” (out on DVD). Those huge skeletons of the brontosaurs filling the great halls of museums might lose pride of place in the light of many startling discoveries made in the present century, especially in China and Africa. </p> <p>Narrated by John Hurt, the series recreates the lives and habitats of these newly identified reptiles. Among them, a pair beast that roamed the North African shore that suggests the worst nightmares of horror fiction: The 11-ton fish-eating spinosaurus, with its long jaw and conical teeth. Climate change killed the spinosaurus 92 million years ago when rising sea levels swallowed the swamps where it fed and drove it inland, where it became food for other monsters. </p> <p> A peculiar feathered dinosaur whose fossil was recently unearthed in China provides more evidence for the long-suspected evolutionary link between reptiles and birds. It was a whimsical little bug-eating thing, the size of a pigeon, with spindly fingers, big bulging eyes, a feathery body and long ribbon-like tail feathers. </p> <p>“Dinosaur Planet” features serviceably gruesome, flesh-tearing computer animation of lizard-on-lizard violence; the big brutes fought over territory and the carnivores ate each other and anything else in their path. While speculation is inevitable in recreating the past out of dry bones, some of the evidence is striking, including the tooth of a particular species embedded in the fossil neck of another. </p>