Wednesday, July 1, 2015

Canada Day Special

With Canada Day today, I've decided to showcase a Canadian fauna of dinosaurs. This one is the richest, most distinctive and one of the oldest. 

The Red Deer River flows south from the Canadian Rockies, the Sawback range of Alberta. The river passes through plains, forests, and badlands of southern Alberta before merging in the South Saskatchewan River in Saskatchewan province. Along the shores are exposed stones, cliffs, and hills of rock 75 million years old. For over a century, its secrets have been revealed, producing one of the richest fossil sites in the world. These dinosaurs are part of North American culture, and have become pillars of dinosaur research around the world and for years to come.

Welcome my friends, to Dinosaur Provincial Park, Alberta.






 After the fierce North-West war between an alliance of Metis, Cree and Assibone  and the Canadian government in 1885, Alberta and Saskatchewan were settled by Anglo-Canadians from the east.  The region's geology gained national attention, and was fueled by parallel developments across the border.


Stationed at a garrison, Lawrence M Lambe grew very intrigued by the Red Deer river valley, especially at a point where it eroded away much of the surrounded rock, exposing sediments almost a 100 million years old. Signing up for the Geological Survey of Canada, Lambe offered to lead an expedition to the river in search of specimens.  Along with him were a family of Americans the Sternbergs. The father, Charles, had worked under Cope, and was very excited about these new sites.


The first dinosaur ever found in this formation was Troodon, a mysterious serrated tooth. The great American paleontologist George Leidy described it as a lizard in 1856, but that was only the beginning. Charles W Gilmore of the US National Museum saw a resemblance with Pachycephalosaurus teeth, and named it as one in 1924. However, the Canadian scientist Charles M Sternberg saw more affiliation with meat-eating dinosaurs and considered it akin to his own small birdlike theropod Stenonychosaurus from 1932.   More and more specimens emerged over the years, and eventually, in 1987, Phillip Currie of the Royal Tyrell Museum (more on it later) found that Troodon and Stenonychosaurus were the same animal.  The mystery was solved after 130 years


In 1897, Lambe's expedition hit jackpot. In 1876, the great Edward Drinker Cope found a horned dinosaur, Monoclonius, in Montana, but it was only a portion of frill and horn, not nearly as good as Marsh's Triceratops. Lambe, however, found a nearly complete specimen of horned dinosaur, which he identified as Monoclonius. In 1904 he would go on to describe it, however, as a new species called Centrosaurus.  Centrosaurus would become even better known as more and more specimens emerged, and Lambe's successor Sternberg found an entire herd.


That year's expedition found much else, however.  Lambe found the first armored dinosaur-an armored skull, bone plates, and a tail shaped like a bony club. He called it Stereocephalus tutus, but since the name was preoccupied, he had to rename is as Euoplocephalus. Euoplocephalus and the other armored dinosaurs from the formation were the first look at armored dinosaurs, and the basis for their science and depictions for the next century. They're still the best preserved of the group.

The next year's expedition found another horned dinosaur-Lambe initially thought it was another species of Monoclonius, but Charles Sternberg would find more specimens and  so make Lambe erect it as its own species, Chasmosaurus.


In 1901, Lambe found another new species but again referred it to an existing genus. In this case, it was an ostrich dinosaur, similar to Marsh's Ornithomimus, so Lambe assigned it to the genus. Barnum Brown of the American Museum, however, would find more specimens 13 years later, and established a new genus for them, Struthiomimus. Struthiomimus and Ornithmimus would be the flagship species for the family of ostrich dinosaurs.

Ironically, Lambe would find a species that would be named after him. In 1902, Lambe discovered hadrosaur remains, assigning them as a new species of Leidy's Trachodon.  Ten years later, more distinct remains were found, and so Lambe called them a new genus, Stephanosaurus. However, in 1924, one of Lambe's students, William Parks, separated the excellent "Stephanosaurus" skulls as a new genus from the rest of the scrappy material.The genus' name? Lambeosaurus lambei. Lambeosaurus's distinct look makes it memorable, and so Lambe's contribution to paleontology has been memorialized.


The other one of Lambe's finds was a piece of thick bone, which he labeled Stegoceras validum. He thought it may be another ceratopsian, or even a surviving stegosaur. More specimens were found with teeth, and the teeth reminded paleontologists of Troodon, therefore Stegoceras was considered Troodon. It was finally in 1931 that Gilmore discovered Pachycephalosaurus, and Stegoceras was finally classified correctly as a relation of this new dinosaur. More specimens emerged over the years, and Stegoceras became so well known it became the basis for a lot of Pachycephalosaurus reconstructions until recently. That's right-Stegoceras is now by far the best known pachycephalosaurs.


The aforementioned Barnum Brown was responsible for not only the famous Tyrannosaurus and Ankylosaurus, but for the American Museum's vast collection of Canadian dinosaurs. His first was Corythosaurus casuarius in 1911, not only complete (with skin impressions!) but with an iconic head crest. Corythosaurus became an icon of hadrosaurs, and made a grand debut in the 1933 World's Fair Sinclair Dinosaur exhibit alongside fellow icons Tyrannosaurus, Ankylosaurus, Triceratops, and Brontosaurus.


Now on a roll, Brown, Lambe, and the Sternbergs returned to the river for the rest of the decade, finding dinosaur after dinosaurs. In 1913 alone, Lambe and Robert Sternberg found big-nosed hadrosaur Gryposaurus (which would pop in and out of Brown's Kritosaurus for the next century), the light Tyrannosaur Gorgosaurus (Brown found nearly complete specimens, too), and the spiky-frilled, now iconic Styracosaurus (again, Brown found an excellent one for New York) which would make a film debut in 1933's Son of Kong. 


Interestingly, one of Brown's Gorgosaurs was sold to Chicago's Field museum, where it was mounted in the main hall for 40 years (replaced by a Brachiosaurus). The specimen would be reassigned to Daspletosaurus when the genus was erected by Dale Russell.  Since it was found in this formation and not the Oldman formation, along with other specimens of Daspletosaurus, it is probably a new species.  For more on George the ex-Gorgosaur- http://extinctmonsters.net/2015/01/26/the-glorious-journey-of-gorgeous-george/


The next year Lambe and George Sternberg found long, large-clawed theropod hands, but Lambe died before he could study them. Gilmore looked at them, and gave them the name Chirostenotes. However, their identity was still a mystery until 1976, when Halszka Osmólska, a Polish scientist working in Mongolia, found oviraptorid material very similar to Christenotes. Further remains supported her conjecture, and Currie has since fully described Chirostenotes.
The same year Brown found some small theropod teeth and skull material, but paid it little attention until 1922, when he named it Dromaeosaurus albertensis. In 1969, the material was re-examined by John Ostrom, who had discovered the similar Deinonychus. He compared the material, and decided they were of the same family, as well as Roy Chapman Andrew's similarly scanty Velociraptor. Ostrom reconstructed both Dromaeosaurus and Velociraptor as Deinonychus relatives, and called a new family for them, Dromaeosauridae.   Since then, more of both Velociraptor and Dromaeosaurus have been found, and they are indeed those fierce, fast little predators, raptors.

Next year, Brown found two excellent specimens-the spiky ankylosaur Edmontonia rugosidens (called Palaeoscinus, a dubious tooth,  by William Matthew) and the hadrosaur Prosaurolophus maximus, both prizes for New York. The Sternbergs found these species soon enough, and got some for Canada.  In 1917 Lambe found one more dinosaur with the Sternbergs, Edmontonia's sister species Panoplosaurus, and sent it along with a Prosaurolophous to the new Royal Ontario Museum.

The Royal Ontario museum sent another expedition in 1920, where students of the University of Toronto discovered a new hadrosaur. Parks called it Parasaurolophus longiceps, and its iconic crest became a symbol of the museum. Parasaurolophus' unique look has made it so iconic it's gone on to eclipse Brown's Corythosaurus and rival Lambe's Edmontosaurus in popular culture.

In 1924, Parks went on to discover a sister species to Euoplocephalus, Dyoplosaurus.  In 1933 Brown found what he thought was another species of Lambe's Chasmosaurus, but it has since been reclassified as a new genus by Nicholas R. Longrich, Mojoceratops.  In 1936 Charles Sternberg found what looked like Chrostenotes, a related oviraptorasaur Caenagnathus. 1943 saw Brown finding what he thought was a new species of Stegoceras, but would turn out to be its own species Hanssuesia according to Robert M. Sullivan.


1955 saw a new milestone-the fossil producing area was registered as a national park called Dinosaur Provincial Park. This would protect the fossils from poaching and give government resources in the scientific digs. 

The 1970s added a new genus of dromeosaur, discovered by an amateur, Irene Vanderloh, and named Saurornitholestes by Hans Sues, and a relative of Stegoceras named Gravitholus by W. P. Wall and Peter Galton. 

In 1985, another milestone was made-the volume of fossils became such that a dedicated museum was built for it. This museum, called the Royal Tyrell Museum of Paleontology in Drumheller, is a national hub of paleontology, and a center of research that has even usurped the Royal Onatrio Museum and Canadian Museum of Nature in its importance. Believe me, if I ever make it to Alberta, this will be the first thing I ever see

One of the TMPs's paleontologists, the late great Elizabeth L. Nicholls, collected a specimen of tiny dromeosaur in 1982. Longrich and Currie finally described it in 2009 as Hesperonychus elizabethae in her memory.  In 2012, Cleveland's Michael Ryan and Toronto's David Evans joined Currie to describe a 1995 find of a small ceratopsian, Unescoceratops koppelhusae. In 2001, a new species of Chasmosaurus, C. irvinensis was described by R. B. Holmes, Catherine A. Forster, M. J. Ryan and K. M. Shepherd. In 2010, however, this species was given its own species Vagaceratops by Forster,
Scott D. Sampson, Mark A. Loewen, Andrew A. Farke, Eric M. Roberts, Joshua A. Smith, and Alan L. Titus. It has become the iconic species, along with Daspletosaurus torosus, of the Canadian Museum of Nature, and its models adorn the museum.  In 2013, Longrich et al named a new Caegnosaur, Leptorhynchos, that outlasted the other two Dinosaur Park species.

The most recent find from Dinosaur Park is Mercuriceratops gemini, described by Ryan, Currie, Evans and Lowen in 2014. Mercuriceratops resembles Chasmosaurus, but is the earliest chasmosaur from Canada and probably an ancestor to Chasmosaurus.


Happy Canada Day to my friends in Canada, and I hope the TMP, ROM, and CMN see many visitors today and for many years to come!

3 comments:

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  2. Fossils and signs from history are stored in the rocks of the Earth so its imperative to understand how the Earth came about and understand that the world is dynamic and fluid. The world has undergone change constantly, for there wasn’t always seven continents.

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  3. Good sharing !!!
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    Thanks...

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