Brachylophosaurus

Taxobox

---

name = "Brachylophosaurus"
fossil_range = Late Cretaceous
regnum = Animalia
phylum = Chordata
classis = Sauropsida
superordo = Dinosauria
ordo = Ornithischia
subordo = Ornithopoda
infraordo = Iguanodontia
superfamilia = Hadrosauroidea
familia = Hadrosauridae
subfamilia = Hadrosaurinae
genus = "Brachylophosaurus"
genus_authority = Charles M. Sternberg, 1953
species = "B. canadensis"
binomial = "Brachylophosaurus canadensis"
binomial_authority = Charles M. Sternberg, 1953

"Brachylophosaurus" (pronEng|brəˌkɪləfəˈsɔrəs or IPA|/ˌbrækiˌloʊfəˈsɔrəs/ BRAK-ee-LOH-fo-SAWR-us) meaning "short-crested lizard" (Greek "brachy" = short + "lophos" = crest + "sauros" = lizard, referring to its small crest) was a mid-sized member of the hadrosaurid family of dinosaurs. It is known from several skeletons and bonebed material from the Judith River Formation of Montana and the Oldman Formation of Alberta,cite book |last=Horner |first=John R. |authorlink=Jack Horner (paleontologist) |coauthors=Weishampel, David B.; and Forster, Catherine A |editor=Weishampel, David B.; Osmólska, Halszka; and Dodson, Peter (eds.)|title=The Dinosauria |edition=2nd |year= 2004|publisher=University of California Press |location=Berkeley |isbn=0-520-24209-2 |pages=438-463 |chapter=Hadrosauridae ] living roughly 75 million years ago.

Description

This animal is notable for its bony crest, which forms a flat, paddle-like plate over the top of the skull. Some researchers have suggested it was used for pushing contests,cite journal |last=Hopson |first=James A. |year=1975 |title=The evolution of cranial display structures in hadrosaurian dinosaurs |journal=Paleobiology |volume=1 |issue=1 |pages=21–43 ] cite book |last=Weishampel |first=David B. |authorlink=David B. Weishampel |coauthors=and Horner, Jack R. |editor= Weishampel, David B.; Osmólska, Halszka; and Dodson, Peter (eds.)|title=The Dinosauria |edition=1st |year=1990 |publisher=University of California Press |location=Berkeley |isbn=0-520-06727-4 |pages=pp. 534-561 |chapter=Hadrosauridae] but it may not have been strong enough for this. Other notable features are the unusually long forelimbs and the beak of the upper jaw being wider than other contemporary hadrosaurs.

Apart from the above, "Brachylophosaurus" was a typical hadrosaur which reached an adult length of 9 meters (30 ft). Like other hadrosaurs, "Brachylophosaurus" possessed features like cheeks to keep fodder in the mouth and dental batteries consisting of hundreds of teeth. These teeth were put to efficient use by the hadrosaur's ability to chew efficiently, a feature rare among reptiles, but common among ornithischian dinosaurs like "Brachylophosaurus".

In 2003, evidence of tumors, including hemangiomas, desmoplastic fibroma, metastatic cancer, and osteoblastoma was discovered in fossilized "Brachylophosaurus" skeletons. Rothschild "et al." tested dinosaur vertebrae for tumors using computerized tomography and fluoroscope screening. Several other hadrosaurids, including "Edmontosaurus", "Gilmoreosaurus", and "Bactrosaurus", also tested positive. Although more than 10,000 fossils were examined in this manner, the tumors were limited to "Brachylophosaurus" and closely-related genera. The tumors may have been caused by environmental factors or genetic propensity.cite journal| last = Rothschild| first = B.M.| authorlink = | coauthors = Tanke, D.H., Helbling II, M. and Martin, L.D.| title = Epidemiologic study of tumors in dinosaurs| journal = Naturwissenschaften| volume = 90| issue = 11| pages = 495-500| publisher = | location = | date = 2003| url = http://www.springerlink.com/content/ktqqkxcqdc620keb/ | doi = 10.1007/s00114-003-0473-9| id = | accessdate = 2008-07-25]

Discovery and later finds

"Brachylophosaurus" was first described by Charles M. Sternberg in 1953 for a skull and partial skeleton which had been found in 1936, and at first thought to belong to "Gryposaurus" (or "Kritosaurus" as it was known at the time).cite journal |last=Sternberg |first=Charles M. |authorlink=Charles Mortram Sternberg |year=1953 |title=A new hadrosaur from the Oldman Formation of Alberta: Discussion of nomenclature |journal=Canadian Department of Resource Development Bulletin |volume=128 |pages=1–12] This remained the only described specimen until the 1980s, when Jack Horner described "B. goodwini" in 1988. This species was found in the Judith River Formation of Montana.cite journal |last=Horner |first=John R. |authorlink=Jack Horner (paleontologist) |year=1988 |title=A new hadrosaur (Reptilia, Ornithischia) from the Upper Cretaceous Judith River Formation of Montana |journal=Journal of Vertebrate Paleontology |volume=8 |issue=3 |pages=314–321] Later work indicated that the differences were probably not enough to justify the second species, and that some of the perceived differences were due to a misoriented skull bone.cite journal |last=Prieto-Marquez |first=Alberto |year=2005 |title=New information on the cranium of "Brachylophosaurus", with a revision of its phylogenetic position |journal=Journal of Vertebrate Paleontology |volume=25 |issue=1 |pages=144–156 |doi=10.1671/0272-4634(2005)025 [0144:NIOTCO] 2.0.CO;2] "Brachylophosaurus" has subsequently become better known from fossils found in Montanta than Alberta, despite its species name "canadensis".

In 1994, amateur paleontologist Nate Murphy discovered an immaculate, complete and uncrushed brachylophosaur skeleton which he nicknamed 'Elvis'.cite web|url=http://www.montanadinosaurdigs.com/brach.htm|title=Brachylophosaurus dinosaur discovery|date=2002|publisher=Judith River Dinosaur Institute|accessdate=2008-07-13] More impressive finds lay ahead for Murphy and his team from the Judith River Dinosaur Institute. In 2000, 'Leonardo', a fully articulated and partially mummified skeleton of a subadult brachylophosaur, was discovered.cite book |last=Murphy |first=Nate L. |coauthors=Trexler, David; and Thompson, Mark |year=2006 |chapter="Leonardo," a mummified "Brachylophosaurus" from the Judith River Formation |editor=Carpenter, Kenneth (ed.) |title=Horns and Beaks: Ceratopsian and Ornithopod Dinosaurs |publisher=Indiana University Press |location=Bloomington and Indianapolis |pages=117-133 |isbn=0-253-34817-X] [cite news | first= | last= | coauthors= | title=Dear Mummy: Rare fossil reveals common dinosaur's soft tissue: Science News Online, | date=2002-10-19 | publisher= | url =http://www.sciencenews.org/articles/20021019/fob2.asp | work = | pages = | accessdate = 2007-07-06 | language = ] It is considered one of the most spectacular dinosaur finds ever, and was included in the "Guinness Book of World Records".cite web|url=http://www.montanadinosaurdigs.com/brachleo.htm|title=Brachylophosaurus dinosaur discovery|date=2002|publisher=Judith River Dinosaur Institute|accessdate=2008-07-13] They subsequently excavated 'Roberta,' an almost complete gracile skeleton, and 'Peanut', a partially preserved juvenile with some skin impressions.cite web|url=http://www.greatfallstribune.com/apps/pbcs.dll/article?AID=2008806010302|title=Malta dinosaur museum read to roar|last=Newhouse|first=Eric|date=2008-06-01|publisher=Great Falls Tribune|accessdate=2008-07-13] In May 2008, Steven Cowan, public-relations coordinator at the Houston Museum of Natural Science, discovered a "Brachylophosaurus" skeleton subsequently dubbed "Marco" from the same area as Leonardo.cite web |url=http://greatfallstribune.com/apps/pbcs.dll/article?AID=/20080602/NEWS01/806020303 |title=Badlands yield another impressive fossil |last=Newhouse |first=Eric |date=2008-06-02 |publisher=Great Falls Tribune|accessdate=2008-07-13]

ee also

Related animals
* "Maiasaura"
* "Prosaurolophus""Brachylophosaurus." In: Dodson, Peter & Britt, Brooks & Carpenter, Kenneth & Forster, Catherine A. & Gillette, David D. & Norell, Mark A. & Olshevsky, George & Parrish, J. Michael & Weishampel, David B. "The Age of Dinosaurs". Publications International, LTD. p. 134. ISBN 0-7853-0443-6.]

References

External links

* [http://www.montanadinosaurdigs.com/brach.htm The Judith River Dinosaur Institute]
* [http://skeletaldrawing.com/psgallery/pages/brachylophosaurus.html "Brachylophosaurus"] from SkeletalDrawing.com
* [http://www.dinodata.org/index.php?option=com_content&task=view&id=6114&Itemid=67 "Brachylophosaurus"] at DinoData