From - Mon Aug 20 10:48:10 2001 Return-Path: Received: from peakpeak.com (tz0099.peakpeak.com [207.174.69.99]) by gash2.peakpeak.com (8.9.3/8.9.3) with ESMTP id CAA08357; Tue, 12 Jun 2001 02:18:02 -0600 Sender: snowbear@gash2.peakpeak.com Message-ID: <3B25D0D2.4147092A@peakpeak.com> Date: Tue, 12 Jun 2001 02:20:35 -0600 From: Pam North X-Mailer: Mozilla 4.61 [en] (X11; U; Linux 2.2.12-20 i586) X-Accept-Language: en MIME-Version: 1.0 To: "Green, Guerin" , "Douglas, Laura" , "North, Pam" , Vyner Jeff Subject: Article Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Status: X-Mozilla-Status: 8001 X-Mozilla-Status2: 00000000 X-UIDL: 391deae70000155f COLORADO'S COLOSSAL CRITTERS by Pam North Their names are almost as big as the sizes of these long-extinct beasts. Allosaurus, Diplodocus, Apatosaurus, Camarasaurus, Stegosaurus, Camptosaurus, Ceretosaurus, and Dryosaurus. Brachiosaurus, Triceratops and Tyrannosaurus Rex. Colorado had all these, and many more besides. From the late Jurassic period 150 to 163 million years ago, through the Cretaceous period 65 to 144 million years ago, at least 26 types of dinosaurs inhabited this state, and left their bones to tell the tale. Dinosaurs were part of ecosystems that changed over time, but pieces of the past remain as a time capsule from an ancient world. These puzzle pieces are ardently studied by scientists seeking clues to solve the mysteries of what occurred eons ago. What caused the demise of these creatures? Theories abound: giant meteor or comet impacts, volcanic eruptions, radiation from a nearby supernova, changes in climate, diseases, predation of dinosaur eggs by early mammals. One of the most popular current theories seems to be that a giant meteor, perhaps about 10 km in diameter, struck the earth at the end of the Cretaceous period, causing a dramatic and devastating climate change. The immense cloud of dust thrown up into the atmosphere by the collision blocked the sunlight and darkened the sky for months, wreaking havoc on the photosynthesizing organisms both on land and in the sea, and disrupting the essential food chains. Another theory with merit involves obliquity, which controls how much solar heating various latitudes of the earth have received at various times, and the resulting climatic changes which could have spelled the end for the dinosaurs. Whatever the cause, somewhere in the range of 20% to 25% of all species extant at the beginning of the Cretaceous period were extinct by its close, or shortly thereafter. Unless a real-life Jurassic Park happens at some time in the future, the only way Colorado inhabitants are ever going to meet face-to-face with dinosaurs is to view exhibits of their fossilized bones, and in that regard there are some superb museums and excavation sites in the state where this can be accomplished. Dinosaur National Monument, encompassing 210,000 acres, is located where spectacular canyons were cut by the Yampa and Green Rivers through upfolded mountains. The area, straddling the border of northwestern Colorado and northeastern Utah, has yielded a large number of complete dinosaur skeletons, both juvenile and adult, since 1909. Hundred of bones were found in the river, buried with sand and mud after the creatures had died; the burial helped preserve the bones as well as the fossils. A visitor center 7 miles north of Jensen, Utah is built around a wall containing hundreds of dinosaur bones partially exposed and left in place. Travelers to the Grand Junction and Fruita area may want to include a stop at Dinosaur Journey, the paleontology and natural history division of the Museum of Western Colorado. It features exhibits that include specimens of world-wide importance, pioneer paleontology, ancient trackways and animated half-size dinosaurs, and it also has a working paleontology lab on view for visitors. Dinosaur Depot, in Canon City, is housed in a historic fire station built in the 1930s. The visitor center there has a working preparatory lab and interpretive displays. Closer to home is the Morrison Natural History Museum, which has preserved trackways of dinosaurs that roamed the area. Just down the hill is Denver's Museum of Natural History, which boasts a fine collection of dinosaur specimens of its own, and has a working lab where paleontologists can be viewed doing their research. The remains of these earthly giants are sure to bring a feeling of awe to whoever stands at the feet of any of the huge resurrected dinosaur skeletons. Gilpin County residents only have to watch out for bears and mountain lions---it could be much worse. Photos for article: http//:www.areaparks.com/dinosaur/dinosaurs.html (illustration of dinosaur) http://www.areapars.com/dinosaur/ (photo of Dinosaur National Monument)