The call coming from the Dakota Grasslands summons the watchers when sail-back reptiles are noticed there. While doing their usual routine in this mission, they are unexpectedly attacked by those sail-back reptiles and some other animals. With these various attacks in different places, the team starts to suspect and wonder if an unknown foe is behind this. They end up in a showdown and discover who the villain really is. How will they be able to foil the plot of this new enemy?

Markie is a regular ten-year-old boy who has a normal life. That is until he uses his dad's time opener and accidentally blows it up, leaving the US parks vulnerable to prehistoric and extinct animals. Fortunately, Markie forms a team that deals with the animals, which has him, his friends, and some new companions in it. Now they go on their first adventure to New Mexico to deal with an animal called an Ambulocetus. But will Markie and the group be able to deal with it all by themselves?

In this adventure, Markie and the team are heading for California. In the San Bernardino National Forest, there is trouble brewing. Saber-toothed tigers and giant short-faced bears are creating great havoc. They are really dangerous and put the team in extreme situations. However, things are not what they seem. An unseen figure is watching the team's movements and is doing whatever it can to hinder their efforts in succeeding in this mission. What could possibly happen?

When Markie and the team are called to the High Schells Wilderness in Nevada, they think that the situation is going to be easy. But when they get confronted by predatory dinosaurs and get trapped in another time, things change. They now all have to survive and wait until a solution appears. This will be quite an adventure for the watchers and the 5Ds.

Markie is a regular ten-year-old boy who has a normal life. That is until he uses his dad's time opener and accidentally blows it up, leaving the US parks vulnerable to prehistoric and extinct animals. Fortunately, Markie forms a team that deals with the animals, which has him, his friends, and some new companions in it. Now they go on their first adventure to New Mexico to deal with an animal called an Ambulocetus. But will Markie and the group be able to deal with it all by themselves?

Features time travelling natural history expert, Nigel Marven, as he rescues endangered dinosaurs from extinction and establishes a prehistoric wildlife sanctuary.

In this next adventure, the Watchers' destination is for Gee Creek Wilderness in the state of Tennessee, where there have been reports of great auks--penguin-like flightless birds. When they attempt to send them back to their time, the birds do not want to go back there. Even more unexpected, the Watchers end up in the time the great auks are from. They then get captured by Vikings, who work for none other than LM himself. There is also something Markie doesn't know that will be shocking and very surprising to him. Who will rescue the watchers from the villain's grasp?

A companion volume to the 3-D "Sea Monsters" film reveals the terrifying predators that lurked in the underwater Cretaceous world, in a volume that also profiles the scientists who study these ancient monsters and the technology that made the film possible.

Laugh and learn with fun facts about prehistoric mammals including saber-toothed cats, dire wolves, giant horses, Stone Age humans, and more—all told in Dr. Seuss’s beloved rhyming style and starring the Cat in the Hat! “I’m the Cat in the Hat. Oh, please turn the page to discover some mammals from the Great Ice Age!” The Cat in the Hat’s Learning Library series combines beloved characters, engaging rhymes, and Seussian illustrations to introduce children to non-fiction topics from the real world! Travel back in time and learn: • the difference between mammoths and mastodons • how giant sloths grew as big as elephants • how we study fossils to guess how animals looked and behaved • and much more! Perfect for story time and for the youngest readers, Once upon a Mastodon: All About Prehistoric Mammals also includes an index, glossary, and suggestions for further learning. Look for more books in the Cat in the Hat’s Learning Library series! If I Ran the Horse Show: All About Horses Clam-I-Am! All About the Beach Miles and Miles of Reptiles: All About Reptiles A Whale of a Tale! All About Porpoises, Dolphins, and Whales Safari, So Good! All About African Wildlife There's a Map on My Lap! All About Maps Oh, the Lavas That Flow! All About Volcanoes Out of Sight Till Tonight! All About Nocturnal Animals What Cat Is That? All About Cats Oh Say Can You Say What's the Weather Today? All About Weather The Cat on the Mat: All About Mindfulness

Collects writings by experts in paleontology, from John Horner on dinosaur families to Robert Bakker on the latest wave of fossil discoveries.