Any copying, redistribution or retransmission of any of the contents of this service without the expressed written permission of the American Geosciences Institute is expressly prohibited. "Without considering changes in shape throughout ontogeny, we overestimate dinosaur diversity and hence produce an unrealistic view of the paleoecology of these animals," Scannella said. It very much resembled its cousin Triceratops, but had a much longer frill, with two large holes (or fenestrae).In 2009 researchers under supervision of Jack Horner argued that Torosaurus was the oldest form of Triceratops. Andrew Farke, curator of paleontology at the Raymond M. Alf Museum of Paleontology in Claremont, Calif. Michael Ryan, curator of vertebrate paleontology at the Cleveland Museum of Natural History in Ohio, After hurricanes, U.S. beach homes are rebuilt bigger, Geoethics in the Field: Leading by Example, Inside the inferno: How large firenadoes form, Wind or water? All of this has pointed to one conclusion, Triceratops and Torosaurus (and also Nedoceratops) are all one species in different growth stages, Triceratops is the sub-adult, Nedoceratops is the transitional form, and Torosaurus is the adult. These were the magnificent cattle of the Cretaceous period. But no one had studied that possibility until now. It’s not unprecedented for scientists to determine that what were previously classified as distinct dinosaurs were actually just different life stages of the same species. Among the larger ceratopsians, Torosaurus is similar in size and appearance to its relative, Triceratops. Three species have been named, Torosaurus latus, T. gladius, and T. utahensis. "It is possible that mortality was fairly high for Triceratops before they reached their fully mature morphology.". They found that Torosaurus skulls followed growth patterns distinct from Triceratops skulls. From CalAcademy and the University of California Museum of Paleontology, a great introduction on how the Triceratops (named in 1889) and the Torosaurus (named in 1891) are actually the same dinosaur at different stages of life. By Olivia Solon, Wired UK A newly discovered horned dinosaur called Titanoceratops appears to have reigned long before its more famous descendants, Triceratops and Torosaurus. But if similar dinosaur species turn out instead to be babies, teenagers and adults of the same species, then the kinds of ecological questions scientists ask will be different, he says. Torosaurus had giant holes in its frill. Neither your address nor the recipient's address will be used for any other purpose. The pair cut samples from the horns of several Triceratops and Torosaurus specimens, and noticed the Torosaurus skulls had more bone remodeling than the most mature Triceratops samples, indicating a more advanced age for the Torosaurus specimens. Mw7.0 Greek islands off the coast of western Turkey, Meridional Heat Transfer - Ocean and Atmosphere, Today's Climate Change and the Permian-Triassic Boundary, Science X Daily and the Weekly Email Newsletter are free features that allow you to receive your favorite sci-tech news updates in your email inbox. "Skepticism is important and a good thing," Scannella commented. About 20 years ago, paleontologists John Ostrom of Yale University in New Haven, Conn., and Peter Wellnhofer of the Bavarian State Collection for Paleontology and Geology in Munich, Germany, first suggested Triceratops and Torosaurus might be members of the same species, Scannella says, with Torosaurus, the larger animal, actually being a male Triceratops and the smaller Triceratops being females. Torosaurus is a ceratopsid genus first identified from a pair of skulls in 1891, two years after the identification of Triceratops. They added that the discovery contributes to an unfolding theory that dinosaur diversity was extremely depleted at the end of the dinosaur age. Hurricane Harvey's most destructive force. "Every avenue of investigation we took in attempts to falsify the hypothesis only supported the idea further," Scannella said. NAD: Is nicotinamide adenine dinucleotide a super supplement or all hype? Triceratops and its cousin Torosaurus are not hard to tell apart. Its name means "perforated lizard", although often incorrectly interpreted as "bull lizard". Click here to sign in with or, by Montana State University. Microscope studies revealed that the tissues of Torosaurus specimens are more heavily remodeled than those of even the largest Triceratops, strongly suggesting that Torosaurus specimens are in fact adult Triceratops, Scannella said. Abi Howe, American Geological Institute/ESW Image Bank. Triceratops (left) had a shorter frill than Torosaurus (right). “I just have a hard time swallowing that the transformation would be that great.” He also points out that the fusion of sutures on Triceratops skulls suggest that some of the largest-known Triceratops were indeed fully grown, because such sutures don’t fuse until later in life in animals. In looking at differences between the age groups, Scannella and Horner found that as a Triceratops aged, its frill elongated (approaching the length of Torosaurus) and the bone thinned out — specifically, the bone got thinner in the precise areas where Torosaurus had its holes. Led by Horner, the large-scale project was conducted to reconstruct the ecosystems that existed during the Cretaceous Period that ended about 65 million years ago when there was a mass extinction of dinosaurs. In recent years, in part due to the number of dinosaur species that have been consolidated because of misclassifications, paleontologists have noticed that dinosaur diversity started to decline during the Late Cretaceous, just prior to the asteroid impact 65.5 million years ago that killed off the dinosaurs. "Torosaurus" specimens are much rarer than Triceratops, however. Triceratops had a three-horned skull with a rather short frill, whereas Torosaurus had a much bigger frill with two large holes through it. Finally, the work reminds us that paleontologists are far from knowing all there is to know about even the most iconic dinosaurs, Scannella says. Some of the skulls belonged to juvenile Triceratops and roughly the size of footballs. "By studying patterns of diversity in the past, we attain insights into current ecological trends.". A study has rejected claims that Triceratops and the lesser-known Torosaurus are one and the same type of dinosaur. An adult cassowary, for example, has a large bony crest on its head that develops suddenly at the end of the bird’s adolescence, he says. Older individuals have more bone remodeling, in which older bone is replaced with new bone, so older bone looks different than younger bone. They looked very different, and their skulls changed radically as they matured. The genus Torosaurus resembles Triceratops in geological age, distribution, anatomy and size and it has been recognised as a close relative. Torosaurus was a large ceratopsid dinosaur. Triceratops lived in the Late Cretaceous period, around 68 to 65.5 million years ago. Over the past couple of years, Scannella and Horner traveled to museums across the country to examine more than a hundred Triceratops and Torosaurus specimens. It had a very large skull that was in excess of 8 feet long and had a bony frill behind the back of the skull. MSU paleontologists John Scannella and Jack Horner said in the July 14 issue of the Journal of Vertebrate Paleontology, however, that Triceratops and Torosaurus are actually the same dinosaur at different stages of growth. “Even a dinosaur like Triceratops, which we’ve known about for 120 years, still has surprises in store for us and a lot to teach us about the history of life on this planet.”. They finally agreed that the Triceratops and Torosaurus were the same dinosaur. Both existed around the same time, i.e., the latter part of the Cretaceous Period. They grouped the Triceratops skulls in their sample into different life stages based on certain features that scientists had previously determined changed as the animal got older. All species of horned dinosaurs had epoccipitals and the number stayed the same throughout an animal’s life. Both horned dinosaurs had a giant bony frill that rose up behind the head, but Torosaurus ’ frill was much longer and was adorned with giant holes that were covered by a thin layer of protein called keratin. Triceratops has been documented by numerous remains collected since the genus was first described in 1889, including at least one complete individual skeleton. The paleontologists also examined skulls from several North American institutions, including the American Museum of Natural History in New York, the National Museum of Natural History at the Smithsonian Institution in Washington, D.C., and the Peabody Museum of Natural History at Yale University in New Haven, Conn. Scannella and Horner measured the length, width and thickness of the skulls. They were two of the last species of dinosaurs to exist before mass extinction. In order to get the complete story, you need to have a large sample of fossils from many individuals representing different growth stages.". "We have to put together the story based on fossils. The content is provided for information purposes only. "It may have been the combination of the two factors -- lower diversity and a major global catastrophe -- that resulted in the extinction of all the non-avian dinosaurs.". Some undergraduates also helped prepare the fossils once they were brought back to the Museum of the Rockies. "If Torosaurus is actually the mature form of Triceratops, we must ask why ‛Torosaurus' specimens are relatively rare compared to Triceratops," Scannella said. Thank you for taking your time to send in your valued opinion to Science X editors. Whether looking at entire skulls, skulls without the frill, frills alone, or squamosals, Torosaurus has different morphologies and distinct allometric trajectories compared to Triceratops," the authors write. T’tops departs from the ceratopsian tradition of frill construction. (credit: CBS) More of us may know about the triceratops. “It’s a very creative hypothesis and they’ve got interesting data in support of it,” Dodson says. One valuable piece of data would be the discovery of a skull that exhibits transitional features between Triceratops and Torosaurus, says Michael Ryan, curator of vertebrate paleontology at the Cleveland Museum of Natural History in Ohio. The case that the dinosaurs we have called Torosaurus are simply fully mature Triceratops relies on the hypothesis that we are not going to find juvenile, sub-adult or young adult Torosaurus. You can unsubscribe at any time and we'll never share your details to third parties. Hobbled by its puny arms, T. Rex requires a few precious seconds to lever itself off the ground — by which time Triceratops has lumbered up on … Still, Farke says, several characteristics of Triceratops are unusual compared to other horned dinosaurs, so anything’s possible. Two years later, Marsh named Torosaurus… Such misclassifications have happened because scientists haven’t always considered growth patterns and development when assessing dinosaurs, so it’s likely there are many more cases of mistaken identity out there, says John Scannella, a doctoral student at Montana State University and co-author of the new study, published in the Journal of Vertebrate Paleontology. The Journal of Vertebrate Paleontology is the official journal of the Society of Vertebrate Paleontology. They examined the microstructure, surface textures and shape changes of the frills. Triceratops had many more epoccipitals than Torosaurus, he says, so the new hypothesis would imply that as a Triceratops grew up, it lost some of its epoccipitals — that would be “unprecedented” among horned dinosaurs. Specimens have been observed surviving with their horns, tails and even snouts partially bitten off. By studying the Torosaurus skulls, they also learned that Torosaurus had all the known signs of a mature Triceratops, such as forward-facing horns. Researchers have long recognized similarities between Torosaurus and Triceratops, the main distinctions being that Torosaurus is larger and … The Colorado Rocky’s mascot is … On the top, a Triceratops skull characterized by a short frill without holes. The history of the Triceratops dinosaur is similar to the Torosaurus. Triceratops and its cousin Torosauru s are not hard to tell apart. Recent studies have revealed extreme changes in the skulls of pachycephalosaurs, tyrannosaurs and other dinosaurs that died out about 65 million years ago in North America. He says he’s not “unconvincible,” but needs to see much more data before he would be sold on the idea. Such late blooming is not unheard of in the animal kingdom, Scannella says. Like the triceratops and torosaurus, the dracorex was once thought to be a separate species from the more well-known pachycephalosaurus, the dome-headed dinosaur seen in The Lost World: Jurassic Park. Dinosaur King Statistics Name: Torosaurus latus. When the paleontologists did find "Torosaurus" skulls, the skulls were all large. The confusion over Triceratops and Torosaurus was easy to understand, Scannella said, because juvenile dinosaurs weren't just miniature versions of adults. Both horned dinosaurs had a giant bony frill that rose up behind the head, but Torosaurus’ frill was much longer and was adorned with giant holes that were covered by a thin layer of protein called keratin. googletag.cmd.push(function() { googletag.display('div-gpt-ad-1449240174198-2'); }); Since the late 1800s, scientists have believed that Triceratops and Torosaurus were two different types of dinosaurs. This document is subject to copyright. part may be reproduced without the written permission. Do equations for groundwater flow refer to water density? © 2008-2020. Both lived around between 66.8 and 65.5 million years ago. Triceratops are extremely tenacious and aggressive in temperament. One problem with the idea, he says, relates to the dinosaurs’ epoccipitals, projections of bone that line the edges of the animals’ frills. "Paleontologists are at a disadvantage because we can't go out into the field and observe a living Triceratops grow up from a baby to an adult," Scannella said. In the Late Cretaceous, herds of horned herbivores like these were very common…and attracted many predators. The first, named Triceratops in 1889, had three impressive horns jutting out of its face and a solid, curved frill. The information you enter will appear in your e-mail message and is not retained by Phys.org in any form. If an area was once home to several species of very closely related animals, then scientists need to think about how the animals could have co-existed, in terms of sharing available food resources, for example. Although Scannella and Horner, his advisor, agreed that these dinosaurs might be the same species, they thought the differences between Triceratops and Torosaurus were more likely the result of age than sex. That would make Horner and Scannella’s case even stronger, he says. It also changes the way scientists view dinosaur ecology, Scannella adds. In the 1970s, Peter Dodson, a paleontologist at the University of Pennsylvania in Philadelphia, demonstrated this with duck-billed dinosaurs. Torosaurus. : 31 A new study shows that the Triceratops and the Torosaurus may have been the same dinosaur, because their frills keep growing with age. Scannella said he and Horner tried for three years to look for alternative explanations for their findings. This dinosaur also had a toothless beak and a large, heavy body like a triceratops. Your feedback will go directly to Science X editors. After comparing the skull shape of the triceratops to that of its close relative, the torosaurus, researchers John Scannella and Jack Horner concluded that the triceratops may actually be a juvenile form of the torosaurus (not an entirely different species), as dinosaurs' skulls could change shapes during their lifetime. Last year, paleontologists Jack Horner of Montana State University in Bozeman and Mark Goodwin of the University of California at Berkeley reported in PLoS ONE that two genera of dome-headed dinosaurs — Dracorex and Stygimoloch — were really just young members of Pachycephalosaurus. Andrew Farke, curator of paleontology at the Raymond M. Alf Museum of Paleontology in Claremont, Calif., also finds it hard to believe that Triceratops and Torosaurus were the same animal. Daniel Hendricks, Creative Commons Attribution-ShareAlike 2.0 Generic.