Showing posts with label Andy Farke. Show all posts
Showing posts with label Andy Farke. Show all posts

Wednesday, September 22, 2010

New horned dinosaurs from Utah provide evidence for intracontinental dinosaur endemism

Utahceratops (above) and Kosmoceratops (below).
© Lukas Panzarin
I am super excited to help spread the word on two newly named chasmosaurine ceratopsians: Utahceratops gettyi and Kosmoceratops richardsoni!! I know I have been anxiously awaiting these guys for a while now and I am very happy to see them finally published. Both taxa were found in the Kaiparowits Formation of  Grand Staircase-Escalante National Monument, southern Utah. Utahceratops was discovered in 2000 by Mike Getty and is thus far the most abundant ceratopsian found in the monument, known from 6 localities. It is estimated that Utahceratops would have stood 6 feet tall at the shoulder and hips and was 18 to 22 feet in length, weighing about 3-4 tonnes. Kosmoceratops would have been slightly smaller, perhaps 15 feet  long and 2.5 tonnes, with 15 bony horns/horn-like features on its skull, making it one of the more ornate-headed dinosaur known. Subadults and adults are known for both of these new species.

For those of you who have seen the various talks, and specifically the new paper in the recently published in 'New Perspectives on Horned Dinosaurs' (Getty et al. 2010), referring to these animals as "Kaiparowits New Taxon A" and "Kaiparowits New Taxon B" you will be happy to know that Taxon A is Kosmoceratops and Taxon B is Utahceratops. At least three individuals (an adult and two subadults) of Utahceratops were recovered from one monodominant bonebed, the first of its kind in the Kaiparowits Formation.

Chasmosaurus irvinensis is also addressed and renamed Vagaceratops irvinensis (“wandering horned face”) in this paper, as it was found to share closest affinities not with Chasmosaurus, as originally believed, but with Kosmoceratops. The study has helped to show that there is some sort of northern and southern provincialism taking place during the Campanian stage of western North America, also known as Laramidia [read more here]. Both specimens are curated at the Utah Museum of Natural History in Salt Lake City, Utah, and are currently on display for the rest of this year.

Citation: 
Sampson, S. D., M. A. Loewen, A. A. Farke, E. M. Roberts, C. A. Forster, J. A. Smith, and A. L. Titus. 2010. New horned dinosaurs from Utah provide evidence for intracontinental dinosaur endemism. PLoS ONE 5(9): e12292. doi:10.1371/journal.pone.0012292


REFERENCE:
Getty, M.A., M.A. Loewen, E. Roberts, A. L. Titus, and S.D. Sampson. 2010. Taphonomy of Horned Dinosaurs (Ornithischia: Ceratopsidae) from the Late Campanian Kaiparowits Formation, Grand Staircase-Escalante National Monument, Utah. Pp. 478-494 in M. J. Ryan, B. J. Chinnery-Allgeier, and D. A. Eberth (eds.), New Perspectives on Horned Dinosaurs. Indiana University Press, Bloomington.


From the official press release:

Amazing Horned Dinosaurs Unearthed on “Lost Continent”
Discoveries Include Bizarre Beast with 15 Horns

September 22, 2010 – Two remarkable new species of horned dinosaurs have been found in Grand Staircase-Escalante National Monument, southern Utah. The giant plant-eaters were inhabitants of the “lost continent” of Laramidia, formed when a shallow sea flooded the central region of North America, isolating the eastern and western portions of the continent for millions of years during the Late Cretaceous Period. The newly discovered dinosaurs, close relatives of the famous Triceratops, were announced today in PLoS ONE, the online open-access journal produced by the Public Library of Science.

The study, funded in large part by the Bureau of Land Management and the National Science Foundation, was led by Scott Sampson and Mark Loewen of the Utah Museum of Natural History (UMNH) and Department of Geology and Geophysics, University of Utah. Additional authors include Andrew Farke (Raymond Alf Museum), Eric Roberts (James Cook University), Joshua Smith (University of Utah), Catherine Forster (George Washington University), and Alan Titus (Grand Staircase-Escalante National Monument).

Image of Utahceratops from "The Whirlpool of Life"
The bigger of the two new dinosaurs, with a skull 2.3 meters (about 7 feet) long, is Utahceratops gettyi (U-tah-SARA-tops get-EE-i). The first part of the name combines the state of origin with ceratops, Greek for “horned face.” The second part of the name honors Mike Getty, paleontology collections manager at the Utah Museum of Natural History and the discoverer of this animal. In addition to a large horn over the nose, Utahceratops has short and blunt eye horns that project strongly to the side rather than upward, much more like the horns of modern bison than those of Triceratops or other ceratopsians. Mark Loewen, one of the authors on the paper, likened Utahceratops to “a giant rhino with a ridiculously supersized head.”

Image of Kosmoceratops from "Scratching the Surface"
Second of the new species is Kosmoceratops richardsoni (KOZ-mo-SARA-tops RICH-ard-SON-i). Here, the first part of the name refers to kosmos, Latin for “ornate,” and ceratops, once again meaning “horned face.” The latter part of the name honors Scott Richardson, the volunteer who discovered two skulls of this animal. Kosmoceratops also has sideways oriented eye horns, although much longer and more pointed than in Utahceratops. In all, Kosmoceratops possesses a total of 15 horns—one over the nose, one atop each eye, one at the tip of each cheek bone, and ten across the rear margin of the bony frill—making it the most ornate-headed dinosaur known. Scott Sampson, the paper’s lead author, claimed that, “Kosmoceratops is one of the most amazing animals known, with a huge skull decorated with an assortment of bony bells and whistles.”

Although much speculation has ensued about the function of ceratopsian horns and frills—from fighting off predators to recognizing other members of the same species or controlling body temperature—the dominant idea today is that these features functioned first and foremost to enhance reproductive success. Sampson added, “Most of these bizarre features would have made lousy weapons to fend off predators. It’s far more likely that they were used to intimidate or do battle with rivals of the same sex, as well as to attract individuals of the opposite sex.”

Monumental Dinosaurs on a Small Continent
The dinosaurs were discovered in Grand Staircase-Escalante National Monument (GSENM), which encompasses 1.9 million acres of high desert terrain in south-central Utah. This vast and rugged region, part of the National Landscape Conservation System administered by the Bureau of Land Management, was the last major area in the lower 48 states to be formally mapped by cartographers. Today GSENM is the largest national monument in the United States. Sampson added that, “Grand Staircase-Escalante National Monument is now one of the country’s last great, largely unexplored dinosaur boneyards.”

For most of the Late Cretaceous, exceptionally high sea levels flooded the low-lying portions of several continents around the world. In North America, a warm, shallow sea called the Western Interior Seaway extended from the Arctic Ocean to the Gulf of Mexico, subdividing the continent into eastern and western landmasses, known as Appalachia and Laramidia, respectively. Whereas little is known of the plants and animals that lived on Appalachia, the rocks of Laramidia exposed in the Western Interior of North America have generated a plethora of dinosaur remains. Laramidia was less than one-third the size of present day North America, approximating the area of Australia.

Most known Laramidian dinosaurs were concentrated in a narrow belt of plains sandwiched between the seaway to the east and mountains to the west. Today, thanks to an abundant fossil record and more than a century of collecting by paleontologists, Laramidia is the best known major landmass for the entire Age of Dinosaurs, with dig sites spanning from Alaska to Mexico. Utah was located in the southern part of Laramidia, which has yielded far fewer dinosaur remains than the fossil-rich north. The world of dinosaurs was much warmer than the present day; Utahceratops and Kosmoceratops lived in a subtropical swampy environment about 100 km from the seaway.

Distribution of ceratopsians during the Campanian
stage of the Late Cretaceous period  
Beginning in the 1960’s, paleontologists began to notice that the same major groups of dinosaurs seemed to be present all over this Late Cretaceous landmass, but different species of these groups occurred in the north (for example, Alberta and Montana) than in the south (New Mexico and Texas). This finding of “dinosaur provincialism” was very puzzling, given the giant body sizes of many of the dinosaurs together with the diminutive dimensions of Laramidia. Currently, there are five giant (rhino-to-elephant-sized) mammals on the entire continent of Africa. Seventy-six million years ago, there may have been more than two dozen giant dinosaurs living on a landmass about one-quarter that size. Mark Loewen asks, “How could so many different varieties of giant animals have co-existed on such a small chunk of real estate?” One option is that there was a greater abundance of food during the Cretaceous. Another is that dinosaurs did not need to eat as much, perhaps because of slower metabolic rates more akin to those of modern day lizards and crocodiles than to those of mammals and birds. Whatever the factors permitting the presence of so many dinosaurs, it appears that some kind of barrier near the latitude of northern Utah and Colorado limited the exchange of dinosaur species north and south. Possibilities include physical barriers such as mountains, or climatic barriers that resulted in distinct northern and southern plant communities. Testing of these ideas have been severely hampered by a dearth of dinosaurs from the southern part of Laramidia. The new fossils from GSENM are now filling that major gap.

During the past decade, crews from the University of Utah and several partner institutions (e.g., the Utah Geologic Survey, the Raymond Alf Museum of Paleontology, and the Bureau of Land Management) have unearthed a new assemblage of more than a dozen dinosaurs in GSENM. In addition to Utahceratops and Kosmoceratops, the collection includes a variety of other plant-eating dinosaurs—among them duck-billed hadrosaurs, armored ankylosaurs, and dome-headed pachycephalosaurs—together with carnivorous dinosaurs great and small, from “raptor-like” predators to mega-sized tyrannosaurs (not T. rex but rather its smaller-bodied relatives). Also recovered have been fossil plants, insect traces, clams, fishes, amphibians, lizards, turtles, crocodiles, and mammals, offering a direct glimpse into this entire ancient ecosystem. Most remarkable of all is that virtually every identifiable dinosaur variety found in GSENM turns out to be new to science, offering dramatic confirmation of the dinosaur provincialism hypothesis. Many of these animals are still under study, but two have been previously named: the giant duck-billed hadrosaur Gryposaurus monumentensis and the raptor-like theropod Hagryphus giganteus.

Utahceratops and Kosmoceratops are part of a recent spate of ceratopsian dinosaur discoveries. Andrew Farke, another of the paper’s authors, stated, "The past year has been a remarkable one for horned dinosaurs, with several new species named. The new Utah creatures are the icing on the cake, showing anatomy even more bizarre than typically expected for a group of animals known for its weird skulls."

Clearly many more dinosaurs remain to be unearthed in southern Utah. “It’s an exciting time to be a paleontologist,” Sampson added. “With many new dinosaurs still discovered each year, we can be quite certain that plenty of surprises still await us out there.”


© ReBecca K. Hunt-Foster unless other wise noted

Tuesday, September 15, 2009

Who is up for a good challenge?

For those of us that do research (or try to do research), you are probably familiar with having a few projects sitting around unfinished for a variety of reasons. I know I currently only have one actual manuscript in the works, with words on paper. And I have to give credit for all of that happening to my co-author who is quite a bit more motivated and on top of things than I have been this past summer. I have two other projects that are languishing in the data acquisition stage, and have been for quite some time. If you, like me, need some motivation, I suggest you take up the challenge put forth by Andy of the Open Source Paleontologist and Dave Hone of Archosaur Musings - the Paleo Paper Challenge (or Palaeo Paper Challenge). You can read more about it here and here, but what it boils down too is this:
  1. Sign up to participate over at the Open Source Paleontologist
  2. Get that paper finished by January 1, 2010.
It is that easy (or hard)! I am going to jump on board. Hope to see a few of you there! I am looking forward to both the motivation, support and friendly competition.

Friday, April 3, 2009

Fieldwork Friday #4

Sorry this is late - but it is still Friday (for  a few more seconds...)

What a week! We arrived home from our trip to the Marble Mountains Tuesday. I am home for a week and a half and then we are in and out of town until the second week of May! I should not complain - a little over a week of that is field work.

Our trip to the Mojave was wonderful! We could not have asked for better weather! A little background on the trip – we were in the Marble Mountains south of the Mojave National Preserve of California searching for trilobites in the late Cambrian Latham Shale. My husband has been working there since he was an undergraduate and is gathering data for a presentation he will be giving this fall at the International Conference on the Cambrian Explosion. Last year they collected 147 specimens. This year we collected close to 300 specimens. 

We met Dr. Andy Farke (curator of paleontology at the Raymond M. Alf Museum of Paleontology in Claremont, California) along the road on our way to the site. Andy worked out in the field with us the first day. I had a great time getting caught us with him. We realized it was out first time to do fieldwork together - and we were in the CAMBRIAN! What is the world coming to? We need to get out to the Cretaceous where we belong. ;)

We had great luck at our first site. The area was frequented by many hobby collectors while we were there and we had the pleasure to be seriated with gun fired from the camp below our pits (as their children ran loose on the mountain side trying to find trilobites). But everyone came away with a trilobite and no gun shot wounds, which always makes for a good day.

The second day we worked out first day’s area, and then moved to an area closer to camp. We had moderate success at this site. We worked pits that had been opened by others (minimizing any surface impact) and found an amazing amount of trilobite cephalons in the spoil piles. It appeared that many of the people who were working the area were looking for whole trilobites. I found 2 complete trilobites on this trip. The rest were cephalons (and some pretty nice ones!).



This area provided a nice view and we saw a nice variety of lizards (2 Chuckwalla’s!), a nice variety of spring flowers, some fun weird beetles, and 1 huge scorpion!! The weather was perfect with the exception of a strong wind we had our third night that threatened to take down our tents, and did take out our shade tarp. We all got a nice coating of dust and a free facial that day.


This trip was also our dog Tikka's first field excursion since we have had him. He is an Australian Shepherd/Border Collie mix, and an older dog. He enjoyed going out with us and stayed very close, enjoying any shade he could find. He did not even chase any lizards or bugs, just chilled out and watched us work, snapping at the occasional fly that would bug him. He did really well until the last day. We were returning to a quarry that was up a long shale covered, rocky hill and as soon as he saw where I was headed he sat down on the trail and refused to go any further. We decided, since it was the last day and he was so insistent on NOT going up that trail, to just let him hold down the fort at camp that day. He seemed to be feeling much better, although still sore, that evening.

All in all it was a great trip! Feel free to take a look at my pictures from the trip. I hope to take some pictures soon to share of the curation process and research the trilobites we collected will now be going though.


Olenellus (nevadensis?)



Mesonacis fremonti


Mesonacis fremonti

The brachiopod Paternia pospectensis (below)



Mesonacis fremonti



Olenellus nevadensis


© ReBecca K. Hunt-Foster. Please see the "Fieldwork Friday Rules" about the work I do and collection practicies.