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Museum's Brochure Here Your Self Guided Tour To The Fossil Displays and More We hope this brochure makes it easier for LOOK CAREFULLY, at each dinosaur, you to see and enjoy all the exhibits provided but please, by the museum. Included is a map to assist in DO NOT TOUCH! locating all the exhibits and a brief description of what is on display. The dinosaurs are a Museum Hours: major focus of the museum’s exhibits. Everyday 9:00 a.m. - 10:00 p.m. Summer Hours (May-August) Please find the Map on the back 7:00 a.m. - 9:30 p.m. Tours available. cover to locate various displays. For further information about Western or the Natural History Museum please call 307-382-1600 Cenozoic Era Paleozoic Present to 66 million years ago 245 to 570 million years ago Yellowstone has had 3 major Sea deposits phosphates in explosive eruptions. west, red sand deposits in the east. Global extinction of 2 mill. yrs. Uplift of the western U.S. many marine invertebrates. Buffalo, Bull Lake, Pinedale glaciations. 286 mill. yrs. Wind blown sand forms the Mammals dominate the land. Tensleep, Weber, Casper, Minnelusa formations 24 mill. yrs. Sediments from the Miocene (all oil and gas producers). and Pliocene (2 to 24 mill. yrs.) is preserved in central 360 mill. yrs. Shallow sea covers the entire Wyoming Sweetwater Hills state forming the fossil rich area. End of the Laramide Madison Limestone. mountain building episode. 408 mill. yrs. Uplift in southwest 37 mill. yrs. Time of major deposites of Wyoming, diamond bearing coal, oil shale, and trona. diatremes. Heart Mountain detaches from its origin and forms in 438 mill. yrs. Shallow sea deposits Bighorn Bear Tooth Mountains. dolomite. 58 mill. yrs. The Absaraka volcanics erupt. 570 mill. yrs. Marine sea repeatedly covers Major mountain building Wyoming. Cambrian period begins in the west. beach preserves hard-shelled fossils of all phyla in the Mesozoic Flathead Sandstone. 66 to 245 million years ago Pre-Cambrian Gray shale and sand cover 570 to 3 billion years ago Wyoming in western interior seaway. 1 bill. yrs. Black dike on Mount Moran intruded. 144 mill. yrs. Extinction of the dinosaurs. Sundance Sea covers 1.7 bill. yrs. Continent to continent Wyoming depositing sand collision. Sherman stone followed by red granite intrudes near and green river deposits Laramie. (Morrison). 2.5 bill. yrs. First evidence of soft-bodied 208 mill. yrs. Dinosaurs found in Morrison animals and algae. Formation Deposition of red sand to form the Chugwater 3 bill. yrs. + Metamorphic gneiss and Formation. Early dinosaurs. schist are intruded by granites in the Wind River Range. 1. Triceratops the way across Wyoming to the coast of an inland sea in Nebraska. The main food of the Triceratops was giant palm fronds and other leafy plants we now find fossilized in the Rock Springs area. Paleontologists believe the 6-ton Triceratops lived in herds much like cattle and bison do today. The horns and bony cowl were used for protection, however males may have used them to joist for dominance in the herd. The snapping beak was capable of breaking off small trees and other tough vegetation. The Triceratops species became This rhinoceros-like Triceratops roamed extinct about 67 million years ago. the flat swampy area that was Wyoming 70 The first fossil of the Triceratops was million years ago, during a period of time found in eastern Wyoming near Lance Creek known as the Cretaceous. Wyoming was in 1889. This cast came from the Museum an enormous tropical floodplain extending of Natural History in New York, where the from the mountains of Utah to the west all original is displayed. 2. Plesiosaur high above the water. We now know they could not raise their heads more than a few feet above the waves. With an extremely long neck, it could strike sideways at his prey like a snake. Their chief food was fish. The two spiny fish depicted in the display are Pycnsteroides and are commonly found fossilized in the rocks of the same age as the Plesiosaur. The stomach ribs, called ‘gastralia’ may Plesiosaurs are not really dinosaurs but have helped support the animal’s weight marine reptiles. They swam in the warm while crossing sandbars, deltas, or resting in seas covering Wyoming from 140 to 70 shallow water. Plesiosaurs became extinct million years ago, during the Cretaceous at the end of the Cretaceous Period along Period. The name Plesiosaur means “ribbon with the majority of other marine reptiles and reptile” and is thought to be the origin of the land dinosaurs. Many partial skeletons of mythical Loch Ness Monster. Scientists the Plesiosaur have been found in Wyoming. in the past thought the Plesiosaur paddled through the water with their heads and necks 3. Stegosaurus The purpose of the additional nerve center or “brain” throughout the hip area also remains a mystery. It may have helped to coordinate the moving of the boney plates and the animal’s back legs. The Jurassic period in Wyoming was subtropical and its land surface was low and flat, a partially wooded coastal plain with shallow rivers emptying into an eastern sea. The Stegosaurus could stand on its back The name literally means “roofed legs and feed from trees using the tail to reptile.” This giant reptile, 8 feet tall, 20 maneuver and balance. The snout was tipped feet long and weighing over two tons, lived with a horn-covered beak, but the jaws had at the end of the Jurassic Period more than rather poorly developed teeth. Therefore 145 million years ago. The function of the to aid digestion the animal ate “gizzard back is controversial. It is possible the large stones” which were later regurgitated. bony plates were for protection, especially These polished stones have been found in from the Allosaurs, a group of carnivorous association with Stegosaurus’ remains. Its dinosaurs that lived at the same time. Or diet included a variety of soft marshy and they may have been for controlling body leafy shrubs. The toes were hoof-like with temperature by heating or cooling the blood thick pads. It could probably run at 20 miles that flowed in veins just under the surface an hour. of a hornlike cover. You can see the blood The original specimen was found in 1891 vessel imprints on the surface of the bony at Como Bluffs, Wyoming, and is displayed plates. The two sets of spikes on the end in the American Museum of Natural History, of the tail most likely were for protection. New York. 4. Art Gallery The Art Gallery serves as an adjunct The Art Gallery is directed by Professor to classroom instruction, providing a of Art, Florence McEwin, Ph.D. with display area for six to seven shows per assistance from gallery interns. For year. These exhibits offer the community information about exhibits or gallery an opportunity to view a wide range internship, please contact the Art of techniques, materials, and aesthetic Department at (307) 382-1723. viewpoints of regional and national artists. 5. Xiphactinus audax This monster fish prowled off the shore If you look closely above the center of the ancient coal-forming swamps of Rock fin on the belly of the fish, you may spot a Springs at the same time the Triceratops and small tooth on the ribs, and another on the the Tyrannosaurus rex roamed on the land, gill cover. These are shark’s teeth which between 90 and 67 million years ago. settled down on the top of the dead fish and Note the size of the teeth and the large became fossilized with the skeleton. The jaw structure. This fish ate other fish. Xiphactinus (pronounced zif-ack-tin-us) is Two specimens have been found with 6’ related to the modern herring, fish inside. Its jaw has an extensive hinge This particular specimen came from allowing the animal to swallow other Cove County, Kansas, but fragments of large fish whole. As the fish decayed and numerous individuals of these species have collapsed, the rib bones on the bottom shifted been found in Wyoming, one just five miles slightly in the soft mud due to the weight of east of where you stand now. the carcass above. 6. Sabalites Palm Frond This palm frond and accompanying at that time. The largest fish is a Mioplosus fossil fish date to the middle of the Eocene, species, several are Knightia eocaena, and about 45 million years ago. During this several are Diplomystus dentatus. 14 genera time the Rocky Mountains surrounding of fossil fish, including stingrays, are known the Green River Basin were slowly rising. along with myriads of turtles and various Rivers became temporarily blocked, and crocodiles. Frogs, snakes, lizards, birds, a huge freshwater lake covered most of and even bats have been preserved in its southwestern Wyoming. During this time soft sediment. At least four rookeries of a another lake formed west of Kemmerer and flamingo-like bird have been discovered on it is in this lake’s sediment that the palm Lake Gosiute’s fossil shorelines. frond was found. The climate was subtropical 7. Camptosaurus This reptile lived in the same environment and at the same time as the Stegosaurus, the Jurassic Period, over 145 million years ago. Camptosaurus could walk on two legs or on all fours and weighed less than 1000 lbs. Its horny beak snipped leaves and fruits from trees as it stood on its hind legs. It probably had a slightly bent or crouched walking position and may have been able to run on possibly had cheek pouches to store food as two legs at speeds of up to 20 miles per hour.
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