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Flying Texas reptile: World’s oldest Pteranodon? First specimen of its kind discovered as far south as Texas

Unique specimen is first of its kind discovered as far south as Texas, where it flew over a vast ancient sea

Fossilized bones discovered in Texas from a flying reptile that died 89 million years ago may be the earliest occurrence of the prehistoric creature known as Pteranodon.

Previously, Pteranodon bones have been found in Kansas, South Dakota and Wyoming in the Niobrara and Pierre geological formations. This likely Pteranodon specimen is the first of its kind found in Texas, according to paleontologist Timothy S. Myers at Southern Methodist University in Dallas, who identified the reptile. The specimen was discovered north of Dallas by an amateur fossil hunter who found various bones belonging to the left wing.

Pteranodon was a type of pterosaur that lived about the same time as some dinosaurs, about 100 million to 65 million years ago. The only reptiles to dominate the ancient skies, pterosaurs had broad leathery wings and slim torsos.

Adult pterosaur, toothless variety with about a 12-foot wing span
The specimen identified by Myers is an adult pterosaur of the toothless variety and while larger than most birds, wasn’t among the largest pterosaurs, Myers said, noting it had a wing span between 12 and 13 feet, or 3.6 to 4 meters. It was discovered in the Austin Group, a prominent rock unit in Texas that was deposited around 89 million years ago, early in the geological time period called the Late Cretaceous.

Pterosaurs, many of which survived on fish, lived at a time when a massive ancient sea cut across the central United States. The Western Interior Seaway was a shallow body of water that split North America in half from the Arctic Ocean to the Gulf of Mexico.

More than a thousand Pteranodon fossils have been unearthed from the middle part of the seaway.

No definitive Pteranodon specimens have emerged from the southern part that is now Texas.

The SMU specimen, if it is Pteranodon, would be the first discovered so far south in the Western Interior Seaway, said Myers, a postdoctoral researcher in SMU’s Huffington Department of Earth Sciences.

Myers reported and described the specimen in “Earliest Occurrence of the Pteranodontidae (Archosauria: Pterosauria) in North America; New Material from the Austin Group of Texas” in the Journal of Paleontology.

Left wing suggests Pteranodon; cause of death a mystery
Key to identifying the SMU fossils as Pteranodon is a humerus of 5.7 inches, or 14.5 centimeters. The humerus is the uppermost bone in the wing and attaches to the torso. The humerus of the SMU specimen, while complete, did suffer some damage during fossilization when it became compressed and distorted through millions of years of compaction.

“If it wasn’t crushed so badly, it would be possible to determine if it really is Pteranodon,” Myers said. “These bones are easily flattened. They are hollow inside, because they have to be lightweight to allow a pterosaur to fly. So they compress like a pancake as they’re embedded in layers of rock.”

While it’s difficult to narrow the humerus definitively to a specific genus and species, some features clearly identify the specimen as part of the Pteranodontidae family, most likely the genus Pteranodon. It exhibits, for example, the prominent warped deltopectoral crest that is characteristic of members of the Pteranodontidae family, called pteranodontids, he said.

Discovered along with the humerus were parts of the elongated fourth finger that in pterosaurs forms the wing. The SMU specimen’s metacarpal — at 20 centimeters — is incomplete, missing an estimated 37 percent of its length.

The fossils do not solve the mystery of the reptile’s cause of death, Myers said. But it appears the animal probably died in flight over the sea and then fell into the water. Its carcass probably floated for some time, so that when the flesh decomposed the bones separated at the joints, known as “disarticulation,” before they settled to the sea floor and were buried.

“We know it was disarticulated when it was buried because the bones weren’t preserved in correct anatomical position,” Myers said. “Abrupt truncation of the broken end of one of the bones and infilling of the break with sediment also indicates that the breakage and disarticulation took place prior to burial.”

May be oldest Pteranodon in world
If the specimen represents Pteranodon, Myers said, it would be the oldest one in North America by 1 million to 2 million years, and the second oldest pteranodontid in the world.

Pterosaurs were alive from the Late Triassic — more than 200 million years ago — to the Late Cretaceous, evolving from small-bodied creatures to some of the largest animals to ever inhabit the skies, Myers said. An older pteranodontid specimen, belonging to the genus Ornithostoma, previously was identified in England.

“Any pterosaur material is fairly rare to find unless you have exceptional preservation conditions. They are frail, fragile bones, and they require rapid burial to be well preserved,” Myers said. “The SMU specimen was deposited relatively far offshore in deep water, perhaps 50 to 80 feet deep. It’s fairly exceptional because of the number of elements. Typically you’ll only find one piece, or one part of a piece in the local rock.”

During the Early Cretaceous, many types of pterosaurs lived around the world, Myers said. The earliest ones had thin, razor-sharp teeth. In the transition from Early to Late Cretaceous, the toothed variety disappear from the fossil record and toothless forms, like the SMU specimen, become more common, he said.

Dallas area specimens illustrate pterosaur evolution
North Texas is fortunate to have had both the toothed and toothless kinds discovered in the area, illustrating the evolutionary transition, noted Myers.

Besides the toothless specimen just identified by Myers, an older toothed pterosaur, Aetodactylus halli, previously was discovered in the Dallas area. Aetodactylus, also identified by Myers, lived 95 million years ago.

“This new specimen adds a lot more information about pterosaurs in North America,” Myers said. “It helps constrain the timing of the transition from toothed to toothless because there’s only a few million years separating this specimen and Aetodactylus.”

Amateur fossil collector Gary Byrd of Rockwall, Texas, discovered the new SMU pterosaur fossils about 10 years ago.

A roofing contractor who keeps an eye out for fossils, Byrd made the find after stopping to look at two freshly excavated culverts while driving through a new subdivision in Collin County. Using a hammer and pick he dug out the bones and brought them to SMU paleontologists Louis Jacobs and Dale Winkler. Jacobs and Winkler indicated the fossils were likely a pterosaur. Byrd donated the fossils to SMU’s Shuler Museum of Paleontology.

“I found a couple parts of a fish, and then when I saw these my initial thought was that they weren’t fish,” Byrd recalled. “I kind of knew it was something different — a birdlike thing. It’s very rare you find those thin, long bones.”

This isn’t the first time Byrd has hit it lucky finding fossils. In 1994 he discovered dinosaur bones that he donated to SMU’s Shuler Museum. The specimen was identified as a rare primitive duck-billed dinosaur and named Protohadros byrdi after Byrd. — Margaret Allen

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Health & Medicine Mind & Brain Researcher news SMU In The News

Dallas Business Journal: Firm is out to prevent neuron loss

Investigators at SMU and the University of Texas at Dallas have discovered a family of small molecules that shows promise in protecting brain cells against nerve-degenerative diseases such as Parkinson’s, Alzheimer’s and Huntington’s. SMU’s work is led by Chemistry Department Professor Edward R. Biehl.

Health care journalist Bill Hethcock covered the research for The Dallas Business Journal. Hethcock’s Feb. 25 article “Firm is out to prevent neuron loss” details how Dallas-based startup EncephRx Inc. was granted worldwide license to develop the jointly owned compounds.

EXCERPT:

By Bill Hethcock
Dallas Business Journal

Dallas-based biotech startup EncephRx Inc. is working with researchers at the University of Texas at Dallas and Southern Methodist University to develop treatments for Huntington’s, Parkinson’s and Alzheimer’s diseases. Already, there have been signs of promise in animal testing. The company is seeking $1 million in grants and private equity to begin pre-clinical testing in the next year.

The goal is to develop and commercialize treatments that prevent the progressive loss of neurons that characterize the diseases, said Aaron Heifetz, CEO of EncephRx. Available medications attempt to relieve symptoms, but don’t prevent neuron loss and disease progression, he said.

DBJ subscribers can read the full story

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Health & Medicine Mind & Brain Researcher news SMU In The News Technology

Popular Science: A New Interface For Bionic Limbs

Light bridges the communication gap between man and machine

The monthly science magazine Popular Science covered the research of SMU engineers Marc Christensen and Volkan Otugen who are working to develop technology that will someday help amputees have “feeling” in their artificial limbs.

The research is funded through a $5.6 million grant from the U.S. Department of Defense and industry for a center led by SMU’s Lyle School of Engineering. The goal is to develop revolutionary technology for advanced prosthetic limbs that will help amputees returning from war in Iraq and Afghanistan.

Two-way fiber optic communication between prosthetic limbs and peripheral nerves will be key to operating realistic robotic arms, legs and hands that not only move like the real thing, but also “feel” sensations like pressure and heat.

Popular Science’s coverage is in the March issue: “Talk to the hand: A new interface for bionic limbs.”

Read the full story.

EXCERPT:

By Morgen Peck
Popular Science

The Six Million Dollar Man’s robotic arm worked as seamlessly as his natural one. But in the real world, robotic limbs have limited motions and the user can’t feel what he or she is “touching.” a new approach using optical fibers implanted around nerves could transmit more data and let prosthetics speak to the brain.

Previously, scientists surgically connected electrodes to the nervous system, but they seemed to harm the body’s tissues, making the implant fail within months. In 2005, scientists discovered that they could stimulate a neuron to send a message by shining infrared light on it. Last September, DARPA, the Pentagon’s R&D branch, awarded $4 million to a project led by Southern Methodist University engineers to attempt to connect nerves to artificial limbs using fiber optics.

The team suspects that flexible glass or polymer fiber optics will be more flesh-friendly than rigid electrodes. In addition, optical fibers transmit several signals at once, carrying 10 times as much data as their electrical counterparts. “Our goal is to do for neural interfaces what fiber optics did for the telecom industry,” says electrical engineer Marc Christensen, who is leading the SMU group. Transmitting more information faster should give bionic limbs more lifelike movements.

Talk to the hand: A new interface for bionic limbs.

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Culture, Society & Family Researcher news SMU In The News

British Veterinary Association journal: Sex and the profession

Veterinary Record, the journal of the British Veterinary Association, covers the research of SMU sociologist Anne E. Lincoln in which she explains the changing face of veterinary medicine.

An assistant professor in the Department of Sociology at SMU, Lincoln is an expert on how occupations transition from being either male- or female-dominated.

The article notes that Lincoln’s research has found that women now dominate the field of veterinary medicine — the result of a nearly 40-year trend that is likely to repeat itself in the fields of medicine and law. Lincoln found three factors that appear to be driving the change: the 1972 federal amendment that outlaws discrimination against female students; male applicants to graduate schools who may be deterred by a growing number of women enrolling; and the increasing number of women earning Bachelor’s degrees in numbers that far exceed those of male graduates, Lincoln says.

Read the full story.

Excerpt:

Veterinary Record
WHAT accounts for the increasing proportion of women in the veterinary profession, and does it actually matter?

These are not new questions, but they are worth revisiting in the light of a report in the Journal of the American Veterinary Association this month. In the USA, as in the UK, the gender balance of the veterinary profession has changed dramatically over the past 30 to 40 years; having previously been very much in the minority, women now make up about 50 per cent of the profession, and the proportion is set to rise further given that women account for nearly 80 per cent of students at veterinary school. The report describes a study undertaken in the USA by Anne Lincoln, a sociologist at the Southern Methodist University in Dallas, which tried to find out why this has been happening.

Using data provided by the Association of American Veterinary Colleges, Dr Lincoln examined a number of factors that could have affected enrolment to US veterinary colleges between 1975 and 1995. Enrolment of male students fell from 89 per cent in the 1969/70 academic year to 22.4 per cent in 2008/09, with the switch to a female majority occurring around 1987.

The shift to more female students started after 1972, when legislation was introduced in the USA prohibiting discrimination against female students. “I found that, after 1972, when the barriers to entry were dropped, women began enrolling in larger numbers,” Dr Lincoln said. “Male applicants dropped sharply after 1976, the first year that applicant statistics were collected.”

After that, the findings suggested that, in the USA at least, men were put off going to veterinary school by the increasing enrolment of women — a phenomenon Dr Lincoln referred to as ‘pre-emptive flight’. “There was really only one variable where I found an effect, and that was the proportion of women already enrolled in vet med schools,” she said. “So perhaps a young male student says he is going to visit a veterinary medical school, and when he sees a classroom with a lot of women he changes his choice of graduate school. That is what the findings indicate.”

The study found no evidence that men were more concerned about the cost of tuition and salaries. “There has always been this notion for any field that feminises that women don’t care about salaries because they have a husband’s earnings to fall back on,” Dr Lincoln said. “But this study found that men and women are equally affected by tuition and salaries.” She also noted that, in the USA, where veterinary medicine is a postgraduate degree, “fewer men than women are graduating with a Bachelor’s degree, so they aren’t applying because they don’t have the prerequisites.”

Read the full story.

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Culture, Society & Family

Gender gap: Selection bias snubs scholarly achievements of female scientists with fewer awards for research

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Analysis shows that female scientists win fewer awards for their research, more often for service and teaching

Women scientists must confront sexism when competing for scholarly awards, according to a new analysis.

Research funded by the National Science Foundation and sponsored by the Association for Women in Science found that female scientists win service or teaching awards in proportion to the number of women in the PhD pool for their discipline, says sociologist Anne Lincoln at Southern Methodist University. That’s not the case, however, for awards for their research, says Lincoln, one of three authors on the analysis, which was reported in Nature.

The number of women who win scholarly awards is far fewer, the authors report.

“Using data in the public domain on 13 disciplinary societies, we found that the proportion of female prizewinners in 10 of these was much lower than the proportion of female full professors in each discipline,” the authors write.

Why the gap? Lincoln, an assistant professor in the SMU Sociology Department, and her co-authors point to the award selection process.

An analysis of selection practices found that selection committees carry out their duties with few guidelines, minimal oversight and little attention to conflict-of-interest issues, the authors write. The researchers’ investigation found that the chances a woman will win an award for her research improve if a woman is serving on the committee. The analysis found, however, that many committees have no female members, that few have female chairs, and there are few female nominees, said the authors.

Nomination letters for women typically include personal details and contain stereotypically female adjectives, such as “cooperative” and “dependable,” the authors report in the article.

“Notices soliciting nominations, by contrast, tend to use language that fosters male images, such as ‘decisive’ or ‘confident,'” they say.

Co-authors were Stephanie H. Pincus, founder of the RAISE Project, sponsored by the Society for Women’s Health Research; and biochemist Phoebe S. Leboy at the University of Pennsylvania and past president of the Association for Women in Science.

Seven U.S. science societies are working now with the Association for Women in Science and using the findings to change selection committee practices, say the authors. — Margaret Allen

SMU is a private university in Dallas where nearly 11,000 students benefit from the national opportunities and international reach of SMU’s seven degree-granting schools. For more information see www.smu.edu.

SMU has an uplink facility on campus for live TV, radio or online interviews. To speak with Dr. Lincoln or to book her in the SMU studio, call SMU News & Communications at 214-768-7650.