|Gerry Ohrstrom, left, and Dave Sands, watch Nels Peterson, left, and John Scannella excavate a dinosaur near MSU’s Osh Camp in Mongolia. It was even more primitive than the new species described this month from Choteau. (Photo courtesy of Jack Horner).(Photo courtesy of Jack Horner).|
A paper on the finding was published in September’s issue of the Journal of Vertebrate Paleontology, co-author Jack Horner said Friday after returning from Mongolia where he and his crew found 80 dinosaurs in a week. Horner is curator of paleontology at Montana State University’s Museum of the Rockies. The paper’s lead author was Brenda Chinnery, a former postdoctoral researcher with Horner.
Horner said he found the nearly-complete skeleton in 1983, but it was located in extremely hard rock and took a long time to prepare. He also had to wait about two decades before he found an expert who could identify it. That expert was Chinnery, who specializes in horned dinosaurs. Chinnery had worked for one of Horner’s colleagues at Johns Hopkins University and then came to MSU. She left MSU about two years ago and is now a paleontologist at the University of Texas.
“I knew it was probably a new dinosaur, but it took someone that really knew what they were doing to be able to describe it,” Horner said.
The dinosaur fossil has been stored in the Museum of the Rockies since its discovery, but it will be displayed this winter, Horner said. The skeleton has a reddish tinge because some of the original bone was replaced by jasper. It dates to the early part of the Late Cretaceous Period.
The dinosaur, nicknamed Cera, was named Cerasinops hodgskissi after landowner Wilson Hodgskiss. who gave him permission to collect the skeleton for the Museum of the Rockies, Horner said. The fossil was found south of Choteau, in a different area than the famed Egg Mountain site.
The C. hodgskissi is such a simple specimen that it’s hard to describe in terms of distinguishing characteristics, Horner said. Tests, however, showed that it represents a very primitive species that shares characteristics of Neo-ceratopsian dinosaurs in North America and Asia. Ceratopsian dinosaurs have horns, but these do not.
Chinnery said, “Cerasinops is exciting because of the traits that she has – some are known only from Asian horned dinosaurs and others are known only from North American groups. For example, some Asian groups have extra teeth at the front of the jaw, but until now, this has never been found in a North American horned dinosaur. On the other hand, Cerasinops shares a unique way of chewing food with the other North American groups.”
Horner said he was looking at even more primitive dinosaurs on his recent trip to Mongolia. His team collected more than 80 skeletons, with 70 of them coming from one site. Last year, they collected 67 skeletons at the same site. The Mongolian project is a joint research project between MSU and Mongolia’s Science and Technology University.
|(A) View of right ulna of Velociraptor IGM 100/981. (B) Detail from cast of red box in (A), with arrows showing six evenly spaced feather quill knobs. (C) View of right ulna of a turkey vulture (Cathartes). (D) Same view of Cathartes as in (C) but with soft tissue dissected to reveal placement of the secondary feathers relative to the quill knobs. (E) Detail of Cathartes, with one quill completely removed to reveal quill knob. (F) Same view as in (E) but with quill moved to the left to show placement of quill, knob, and follicular ligament. Follicular ligament indicated with arrow. (Credit: Mick Ellison)|
Scientists have known for years that many dinosaurs had feathers. Now the presence of feathers has been documented in velociraptor, one of the most iconic of dinosaurs and a close relative of birds.
The fossil specimen that the group examined was a velociraptor forearm unearthed in Mongolia in 1998. They found on it clear indications of quill knobs–places where the quills of secondary feathers, the flight or wing feathers of modern birds, were anchored to the bone with ligaments. Quill knobs are also found in many living bird species and are most evident in birds that are strong flyers. Those that primarily soar or that have lost the ability to fly entirely, however, were shown in the study to typically lack signs of quill knobs.
“A lack of quill knobs does not necessarily mean that a dinosaur did not have feathers,” said Alan Turner, lead author on the study and a graduate student of paleontology at the American Museum of Natural History and at Columbia University in New York. “Finding quill knobs on velociraptor, though, means that it definitely had feathers. This is something we’d long suspected, but no one had been able to prove.”
Previous signs of feathers on dinosaurs had been restricted to fossils found in a particular kind of lake sediment that favored preservation of small-bodied animals.
The velociraptor in the current study stood about three feet tall, was about five feet long, and weighed about 30 pounds. Combined with its relatively short forelimbs compared to a modern bird, this indicated it lacked volant, or flight, abilities. The authors suggest that perhaps an ancestor of velociraptor lost the ability to fly, but retained its feathers. In velociraptor, the feathers may have been useful for display, to shield nests, for temperature control, or to help it maneuver while running.
“The more that we learn about these animals the more we find that there is basically no difference between birds and their closely related dinosaur ancestors like velociraptor,” said Mark Norell, a Curator in the Division of Paleontology at the American Museum of Natural History and co-author on the study. “Both have wishbones, brooded their nests, possess hollow bones, and were covered in feathers. If animals like velociraptor were alive today our first impression would be that they were just very unusual looking birds”.
The research team also included Peter Makovicky from the Field Museum in Chicago. The work was supported by the National Science Foundation and the American Museum of Natural History.
This research appears in the Sept. 21 issue of the journal Science.
A team of researchers, including Herman Pontzer, Ph.D., assistant professor of physical anthropology in Arts & Sciences, has determined through analysis of the earliest known hominid fossils outside of Africa, recently discovered in Dmanisi, Georgia, the former Soviet republic, that the first human ancestors to inhabit Eurasia were more primitive than previously thought.
The fossils, dated to 1.8 million years old, show some modern aspects of lower limb morphology, such as long legs and an arched foot, but retain some primitive aspects of morphology in the shoulder and foot. The species had a small stature and brain size more similar to earlier species found in Africa.
“Thus, the earliest known hominins to have lived outside Africa in temperate zones of Eurasia did not yet display the full set of derived skeletal features,” the researchers conclude.
The findings, published Sept. 20 in the journal “Nature,” are a marked step in learning more about the first human ancestors to migrate from Africa.
The lead author of the paper is David Lordpkipanidze, director of the National Museum of Georgia. Collaborators on the study include Pontzer and researchers from Georgia, Switzerland, Italy and Spain.
The new evidence shows how this species had the anatomical and behavioral capacity to be successful across a range of environments and expand out of Africa, said Pontzer, who studies how the musculoskeletal anatomy of an animal reflect its performance, ecological niche and evolutionary history.
“This research tells us that the limb proportions and behavioral flexibility which allowed this species to expand out of Africa were there at least 1.8 million years ago,” Pontzer said.
Dmanisi is the site of a medieval village located about 53 miles southwest of Tbilisi, Georgia on a promontory at the confluence of the Mashavera and Phinezauri rivers. Archaeological exploration of the ruins began in the 1930s, but systematic excavations were not undertaken until the 1980s. Pontzer has been studying the site for more than six years.