Prehistoric sea monsters:

Educational resources for kids (and parents, too)


© 2009 Gwen Dewar, Ph.D., all rights reserved

Prehistoric sea monsters: The Mesozoic marine reptiles

For more than 180 million years, the Mesozoic oceans were dominated by large, predatory sea reptiles:

• the dolphin-shaped ichthyosaurs

• the plesiosaurs, which included the long-necked elasmosaurs and the shorter-necked pliosaurs

• the terrifying, snake-like mosasaurs

Who doesn’t like prehistoric sea monsters? Well, perhaps not everyone. But if your kid likes dinosaurs, or is fascinated by marine biology, he’ll enjoy learning about the extinct sea reptiles, too.

I love these creatures because of the lessons they teach about evolution. It’s easy to see how similar selective pressures (the benefits of being sleek and streamlined in the water; the advantages of having a long snout for snapping up fish) gave rise to similar adaptations in prehistoric sea monsters and modern-day marine mammals. At the same time, some of the Mesozoic forms were weirdly and wonderfully unique.

But where to begin? Here’s a guide to some of my favorite resources about prehistoric sea monsters for school-aged kids and teens.

Reign of the Sea Dragons

by Sneed B. Collard III and illustrated by Andrew Plant (Charlesbridge 2008)

Recommended for ages 8 and up; approximately 60 pages long

In a nutshell: This beautifully-illustrated book provides an excellent, concept-driven overview of Mesozoic sea reptiles. Includes scale drawings, a guide to other resources about prehistoric sea monsters, a glossary, and an index. A great educational value that will offer kids insights into the ways that paleontologists reconstruct the past.

The review:

Books about paleontology for kids are often little more than a collection of illustrations and statistics. Sneed B. Collard III’s Reign of the Sea Dragons is a welcome exception: A primer on the prehistoric sea monsters for kids who want to understand how these creatures lived and how paleontologists piece together the evidence.

Aimed at intermediate readers (aged 8 to 11), the book begins with an admirably brief, 2-paragraph overview and a time chart of the Mesozoic. Thereafter, Collard tackles each major reptile group in turn: ichthyosaurs, elasmosaurs, plesiosaurs, and mosasaurs.

The text emphasizes adaptations. Why did plesiosaurs have such long necks? Why did ichthyosaurs resemble dolphins? Collard also discusses the sorts of evidence that paleontologists use to make inferences about the fossil evidence. Were these prehistoric sea monsters warm-blooded endotherms? Did they give birth on land or in the sea? What color were they? And why did they go extinct?

Collard has a knack for presenting the “big picture”--for providing the conceptual scaffolding that makes a reader feel he’s really learned something. For example, consider this paragraph from the end of the book about the role of competition in the extinction of ichthyosaurs:

“While ichthyosaurs were swimming the seas, new groups of faster, more efficient fish were evolving. The larger of these fish--including the sharks--probably began preying on ichthyosaur young. Perhaps more important, many of the bony fish had now evolved efficient, streamlined bodies that could match the speed of the ichthyosaurs. These faster fish became harder for ichthyosaurs to hunt, and also started outswimming ichthyosaurs for all kinds of prey.”

Clear, concise, and full of concrete imagery. That’s great science writing. And it’s great teaching, too.

And speaking of imagery, there are also many vivid and lovely illustrations by Andrew Plant. In addition to eight full color paintings, there are line drawings throughout the book. And the inside cover features a scale drawing of extinct and modern-day sea creatures, so the reader can see how the sea dragons compare with whales and sharks.

There are other books about prehistoric sea monsters for kids. But, in my opinion, this book delivers the best educational value for the money. Collard hits all the right marks:

• He stays on topic--no lengthy, tedious digressions into how specific fossils were discovered.

• He makes instructive comparisons with living animals.

• He provides kids with insights into the way scientists solve problems.

This is the kind of book that encourages a lifelong interest in natural history. And it might even inspire some kids to become paleontologists.

Chased by Sea Monsters

Three-part BBC series by Impossible Pictures. (Found on the North American March 23, 2004 release DVD Chased by Dinosaurs.)

Recommended for ages 4 and up (but it may be too scary for some kids)

In a nutshell: A mock documentary series featuring computer-animated prehistoric sea monsters and the appealing television naturalist, Nigel Marven. Watch out--the tension and subject matter may disturb younger viewers. But for kids who can handle PG-rated scares, this is fine entertainment. Packaged on a DVD that also includes Chased by Dinosaurs, this series is an excellent value for the money.

The review:

TV host and naturalist Nigel Marven stars in this fictitious documentary. The premise is that Nigel and his crew have traveled back in time to film prehistoric sea monsters.

The charismatic Marven, who ordinarily hosts “real” documentaries, is a convincing actor and fun to watch. Whether he’s inspecting a dead trilobite or diving into a sea of plesiosaurs, Marven seems natural and unaffected. The creatures and habitats are equally convincing--they were recreated by Impossible Pictures, the same people who made the landmark series Walking with Dinosaurs.

The creatures aren’t presented chronologically. Instead, Nigel’s crew ranks the world’s seven most dangerous seas, and visits them in order, beginning with the least dangerous. Some of the prehistoric sea monsters include:

• Astraspis, an armor-plated fish from the Ordovician

• Basilosaurus, an ancient, predatory whale from the Eocene

• Megalodon, a gigantic shark from the Pliocene

• Liopleurodon, a short-necked, Jurassic pliosaur and the largest carnivore of all time

• Tylosaurus, a mosasaur from the Cretaceous

Nigel repeatedly puts himself in danger--rather recklessly at times. He is slashed by sea scorpions, menaced by sharks, and stalked by mosasaurs. In fact, the subject matter may be too scary for some children. But if your kids are old enough to understand that it’s fantasy, the series offers some entertaining and exciting reconstructions of prehistoric sea creatures.

Best of all, this series is available as part of a 150-minute long DVD that includes Nigel Marven’s equally entertaining companion series, Chased by Dinosaurs. That series includes amazingly realistic and imaginative sequences--as when Nigel flies his Ultralight plane amongst a flock of pterosaurs. This is one of my favorite DVD purchases. Don't miss it!

Sea monsters: A prehistoric adventure

National Geographic Film

Recommended for ages 5 and up

In a nutshell: State-of-the-art computer animations presented on a huge IMAX screen. How can pass that up?

The review:

This IMAX movie offers spectacular, super-sized imagery of prehistoric sea monsters. The protagonists are some short-necked plesiosaurs ( Dolichorhynchops ). They look a bit like large, four-flippered penguins with teeth. The film follows one of these creatures throughout her lifespan, and includes encounters with Tylosaurus, a terrifying, 58-foot-long mosasaur.

The film takes full advantage of the gigantic, wrap-around format of IMAX. You’ll see breathtaking sea chases and gorgeous aerial shots of pterosaurs flying above the ocean surface.

Worth seeing? Absolutely. How else can you immerse yourself in a Mesozoic ocean? But it’s not a perfect film. In particular, the story about prehistoric sea monsters is frequently interrupted by scenes of “paleontologists” (rather unconvincing actors) wearing cute REI fashions and driving around in SUVs. I’m not sure what these human dramatizations are supposed to accomplish. Did the film makers think we needed a break from the gorgeous paleontological reconstructions?

In my view, the film would be much better if these rather silly scenes were replaced with brief educational outtakes—mini features about, say, the function of various anatomical traits. And how about using real scientists (who show real enthusiasm) instead of actors?

Websites about prehistoric sea monsters

For more child-oriented information about prehistoric sea monsters, check out the BBC’s paleontology website.

If you are a paleontology die hard, you should also visit Mike Everhart’s guide to prehistoric sea monsters, Oceans of Kansas. The site is rather difficult to navigate (because of its enormous size), and much of the information is technical. But there are some dramatic narratives—-like this “A day in the life of a mosasaur”— that will interest serious-minded, middle- and high-school paleontology buffs.

And, for younger kids, there are a few illustrations of prehistoric sea monsters suitable for coloring.

In addition, take a look at the beautiful paleontological reconstructions of scientific illustrator Karen Carr.

Finally, here’s a handy website presenting reconstructions of what the earth (and it’s oceans) looked like at various times in the past.

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