Did dinosaurs swim? |

This is Dorothy, our resident plesiosaur, or long-neck marine reptile. Dorothy was a swimmer, and not a dinosaur! On this page, you’ll find a package of information (text & video resources) with all of the interesting facts about our ancient marine reptile friend. Scroll down to the bottom of the page to find a series of simple and fun activities for home or classroom learning. 

Dorothy FAQs |

Originally discovered in the Pierre Shale of Western Kansas, this 13-metre-long majestic marine reptile once swam through the Western Interior Seaway, a continental sea which at times split North America in two from North to South during the Cretaceous Period (~80 million years ago). The skeleton suspended in the Wheaton Atrium of the Earth Sciences Building is a resin-cast of the original which was discovered in 1868 in Kansas and described by paleontologist Edward Drinker Cope.

Photo Credit: Philippe Roberge

This particular specimen has an interesting story. In Cope’s initial sketches, he incorrectly reconstructed the elasmosaur with its head placed on its tail. This early mistake started the famous “1870s Bone Wars” during which time paleontologist Othniel Charles Marsh publicly pointed out Cope’s mix-up.

The elasmosaur has B.C. roots as well. The first elasmosaur found west of the Canadian Rockies was discovered in 1988 in shale off the Puntledge River, near Courtenay, BC. Complete specimens of this marine reptile are rare, but partial and fragmentary skulls give us a nearly complete view of the original skeletal arrangement of this bizarre looking animal. Contrary to earlier reconstructions, the length and weight of an Elasmosaurus’s neck would place its centre of gravity far behind its flippers, limiting the animal’s ability to raise its head too far out of the water. It is likely that its neck was held more like a stiffened rod that could be tilted downwards.

Despite its age, the elasmosaur is not a dinosaur, but a marine reptile. The group that contains Elasmosaurs evolved from land living relatives which over time became fully adapted to the marine environment. Elasmosaurs (like whales today) were air breathers and gave birth to live young. The Pacific Museum of Earth does have a spectacular dinosaur fossil in its collection though. In the PME’s main gallery (located in the Earth and Ocean Sciences Main building), you’ll find our Lambeosaur skeleton. This duck-billed hooded dinosaur roamed through what is present-day Alberta approximately 75 million years ago.

Watch our time lapse video of this installation process from September 2018. The skeleton assembly and installation was led by Mike deRoos of Cetacea Contracting, a Salt Spring Island company that specializes in the design and articulation of marine and terrestrial skeletons, and science outreach.

This installation was made possible with the support of Wheaton Precious Metals. The Vancouver-based resource sector company also supported construction of UBC’s Earth Sciences Building.

Drawing Dorothy |

Watch the video below and use the activity sheet at the bottom of this page Fleshing out fossils to create your own paleoart!

Fun marine reptile activities |

We’ve created a series of learning activities for you to explore more about Dorothy in your classroom or home. Click, download (& print) the worksheets below.