Category: Videos

Tiny teeth discovered from Inner Mongolia are new species of today’s birch mouse, rare “living fossil”

Post author By Margaret Allen
Post date May 23, 2011

Birch mouse is now 9 million years older than previously known and migrated from Asia to North America

Tiny fossil teeth discovered in Inner Mongolia are a new species of birch mouse, indicating that ancestors of the small rodent are much older than previously reported, according to paleontologist Yuri Kimura, Southern Methodist University in Dallas.

Fossils of the new species were discovered in sediments that are 17 million years old, said Kimura, who identified the new species and named it Sicista primus to include the Latin word for “first.”

Previously the oldest prehistoric ancestor of the modern-day birch mouse was one that inhabited Inner Mongolia 8 million years ago.

Adding 9 million years to the ancestry of the rodent family that includes birch mice and jumping mice distinguishes this genus, Sicista, as a “living fossil,” Kimura said. That places the genus among some of the most unique rodents on earth — those whose ancestry spans 2 to 3 times the average, she said.

Kimura identified Sicista primus from 17 tiny teeth, whose size makes them difficult to find. A single molar is about the size of half a grain of rice. The teeth, however, are distinctive among the various genera of rodents known as Dipodidae. Cusps, valleys, ridges and other distinguishing characteristics on the surface of the teeth are identifiable through a microscope.

“We are very lucky to have these,” Kimura said. “Paleontologists usually look for bones, but a mouse is very tiny and its bones are very thin and fragile. The teeth, however, are preserved by enamel. Interestingly, small mammal teeth are very diverse in terms of their structure, so from that we can identify a species.”

Kimura reported the new species in the article “The earliest record of birch mice from the Early Miocene Nei Mongol, China” in the scientific journal Naturwissenschaften. Images of the research and expedition are posted on the SMU Research flickr site. Go to SMUVideo’s “Inner Mongolia yields ‘living fossil’” to watch Kimura discuss the research.

An SMU doctoral student in the Huffington Department of Earth Sciences, Kimura was part of the international team that discovered the fossils during expeditions to Inner Mongolia in 2004, 2005 and 2007.

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Microscopic evidence of a living fossil
The new fossils of Sicista primus from the Early Miocene age are also now the earliest known record of Sicista, the birch mouse genus that comprises 13 modern and 7 fossil species, said Kimura. As a result, Sicista now boasts the most ancient ancestry of the 326 genera in the largest rodent suborder to which it belongs, Myomorpha. The suborder includes laboratory mice and rats.

“The birch mouse is a rare case of a small mammal genus persisting from the Early Miocene without significant morphological changes,” Kimura said in reporting the findings.

Rodents, both modern and prehistoric, rank as the most prolific mammals on earth. After the reign of dinosaurs, 65 million years ago, rodents evolved and dispersed worldwide during the Cenozoic, the “Age of Mammals.” They comprise about 42 percent of all living mammals. Scientists know now that only 1.5 percent of modern rodent genera, however, go as far back as the Early Miocene or older.

“Diversity within a rodent genus is not unusual, but the long record of the genus Sicista, first recognized at 17 million years ago, is unusual,” said Kimura. “The discovery of Early Miocene S. primus reveals that Sicista is fundamental to understanding how a long-lived genus persisted among substantially fast-evolving rodent groups.”

Birch mice migrated from Asia to North America
Previously the record for the oldest species of Sicista belonged to an 8 million-year-old species identified in Eurasia, Kimura said.

In identifying the new species, Kimura also reverses the long-held hypothesis that ancestors of birch mice migrated from North America to Asia. That hypothesis has been based on a 14.8 million-year-old specimen from South Dakota, which was identified in 1977 as the separate rodent genus Macrognathomys. Kimura’s analysis, however, concludes that Macrognathomys is actually Sicista. For that reason, she concluded, Sicista first inhabited the forests and grasslands of prehistoric Asia and then dispersed to North America via the Bering Land Bridge, Kimura said.

In a comparison of the molars and premolars from Macrognathomys and Sicista primus, Kimura reported finding 12 shared dental characteristics. In addition, phylogenetic analysis to identify evolutionary relationships indicated that both belong to the same genus, Sicista, she said.

Reconnaissance of earlier Central Asiatic Expedition localities yields small mammals
The teeth of Sicista primus were discovered in fine sediments gathered from Gashunyinadege, a fossil locality in the central region of Inner Mongolia.

Gashunyinadege is one of several fossil localities near Tunggur, a fossil site discovered in the 1920s by the Central Asiatic Expedition, which was led by Roy Chapman Andrews from the American Museum of Natural History.

Kimura is a member of an international scientific team sponsored by the Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology and the Natural History Museum of Los Angeles County. The team’s expeditions have been led by paleontologists Qiu Zhuding, IVPP; Wang Xiaoming, Natural History Museum of Los Angeles County; and Li Qiang, IVPP. Their expeditions retrace important classic localities, as well as prospect new fossil localities.

Kimura and other members of the team discovered the birch mouse fossils by first prospecting Gashunyinadege for small mammal fossils visible to the naked eye. Those fossils indicated the possibility of even smaller mammal fossils, so the team gathered 6,000 kilograms, more than 13,000 pounds, of Early Miocene sediment. Using standing water from recent rains, they washed the sediments repeatedly through continually smaller screens to separate out small fossils. Bags of concentrate containing particles the size of mouse teeth were returned to IVPP laboratories to hunt for fossils with a microscope.

The research was funded by the Institute for the Study of Earth and Man at SMU, Dallas Paleontological Society, Geological Society of America, Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology. — Margaret Allen

SMU is a nationally ranked private university in Dallas founded 100 years ago. Today, SMU enrolls nearly 11,000 students who benefit from the academic opportunities and international reach of seven degree-granting schools. For more information see www.smu.edu.

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

Tags Dedman College, Huffington Department of Earth Sciences, Yuri Kimura

Culture, Society & Family Fossils & Ruins Slideshows Videos

3-D mapping of Guatemala’s “Head of Stone” confirms ancient Maya buildings buried beneath forest cover

Post author By Margaret Allen
Post date April 12, 2011

Mapping of Maya’s “Holtun” site in Central Lakes region of Guatemala locates triadic pyramid, astronomical observatory, ritual ball court, residential mounds, plazas

Archaeologists have made the first three-dimensional topographical map of ancient monumental buildings long buried under centuries of jungle at the Maya site “Head of Stone” in Guatemala.

The map puts into 3-D perspective the location and size of Head of Stone’s many buildings and architectural patterns, which are typical of Maya sites: 70-foot-tall “triadic pyramid,” an astronomical observatory, a ritual ball court, numerous plazas and also residential mounds that would have been the homes of elites and commoners, according to archaeologist Brigitte Kovacevich, Southern Methodist University, Dallas.

The map situates the primary buildings relative to one another and also places them within the context of the site’s hills and valleys in the Central Lakes agricultural region of north-central Guatemala.

The buildings date from 800 B.C. to 900 A.D., says Kovacevich, an expert in Meso-American cultures and co-leader of an international scientific team that has been granted permission by the Guatemalan government to work the site, which has never before been excavated.

Movement to understand early periods, how kingship developed
Known for its far-reaching state-level government, Maya civilization during the “Classic” period from 200 A.D. to 900 A.D. consisted of huge monumental cities with tens of thousands of people ruled by powerful kings, palaces, pyramidal temples and complex political and economic alliances, Kovacevich says.

The ancient culture at its peak during the Classic period has been well-documented by archaeologists studying the civilization’s large urban centers, such as Tikal, which was one of the most powerful and long-lasting of the Maya kingdoms.

In contrast, “Head of Stone,” called “Holtun” in Maya, is a modest site from the “Pre-Classic” period, 600 B.C. to 250 A.D., she says. The small city had no more than 2,000 people at its peak. Situated about 35 kilometers south of Tikal, “Head of Stone” in its heyday preceded the celebrated vast city-states and kingship culture for which the Maya are known.

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To book a live or taped interview with Dr. Brigitte Kovacevich in the SMU News Broadcast Studio call SMU News at 214-768-7650 or email SMU News at news@smu.edu.

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By excavating a small city, Kovacevich says, the archaeologists hope to understand early Maya trade routes and alliances, the importance of ritual for developing political power, how political power emerged, and how kingship lines evolved and solidified.

“There is a movement toward a greater understanding of these early periods, with smaller sites and common people,” says Kovacevich, an assistant professor in SMU’s Anthropology Department. “Little is known about how kingship developed, how individuals grabbed political power within the society, how the state-level society evolved and why it then was followed by a mini-collapse between 100 A.D. and 250 A.D.”

Kovacevich presented “‘Head of Stone’: Archaeological Investigation at the Maya Site of Holtun, Guatemala” during the 76th annual meeting of the Society for American Archaeology in Sacramento, Calif., March 30 to April 3.

Besides Kovacevich, archaeologists on the team and co-authors of the paper are Michael G. Callaghan, University of Texas at Arlington; Patricia R. Castillo, Universidad San Carlos, Guatemala; and Rodrigo Guzman, Universidad del Valle, Guatemala. The 3-D topographic map expands surveys from 1995 and 2002 by Guatemalan archaeologist Vilma Fialko and Guatemala’s Institute of Anthropology and History, which were documented by Fialko and archaeologist Erick M. Ponciano.

Situated in a patch of rainforest on defensible escarpment
Head of Stone today sits in a patch of rainforest surrounded by cow pastures and cornfields on a limestone escarpment, which would have made it highly defensible, Kovacevich says.

Holtun’s structures — more than 100 of them — now are overgrown with a thin layer of centuries-old jungle foliage and soil. The site is about one kilometer long and half a kilometer wide, or almost three-quarters of a mile long and one-third of a mile wide. The large mounds protruding here and there from the jungle floor signal to archaeologists the familiar building arrangements customary at a Maya site, Kovacevich says.

As with most Maya sites, looters have tunneled into many of the important structures. Kovacevich and her colleagues will dig more tunnels to further explore the buildings with the help of Guatemalan experts skilled at working Maya sites.

Key structures: “E Group,” residential group
The 3-D mapping has confirmed an “E Group,” a key Maya architectural structure. Holtun’s “E Group” dates from 600 B.C. to 600 A.D. and consists of stair-step pyramids and elongated buildings that likely served as astronomical observatories central to Maya rituals. A stepped pyramid to the west of a long narrow building directly oriented north-south served as the observational structure and was related to veneration of sacred ancestors, Kovacevich says.

“From the observational structure you can see the sun rising at the different solstices throughout the year, which is very important agriculturally, to know the timing of the seasons and when to plant and when to harvest,” she says. “So the people creating this are harnessing that knowledge to show their followers and constituents that they possibly are even controlling the change of seasons.”

Adjacent to the “E Group” are four structures that face one another around a central patio. The pattern usually indicates a residential group, where cooking and food processing were carried out on the patio, Kovacevich says.

“The closeness of the residential structure to the “E Group” suggests these were very early elites, and possibly kings,” she says. “Kingship was just being established during this period.”

The Maya often left offerings to their ancestors, such as jade or ceramics, at the base of structures.

Triadic pyramid represents Maya mythology?
Besides the “E Group,” a triadic pyramid dating from 300 B.C. to 300 A.D. sits at the north end of the site. As is typical at Maya sites, three pyramids about 10 feet tall sit atop a high platform that rises about 60 feet from the jungle floor, Kovacevich says. One of the pyramids faces south, flanked on either side by the other two, which face inward around a central patio. The platform sits atop — and obscures — an earlier sub-structure platform, buried underground and decorated with monumental masks that are visible from the looters’ tunnels.

“Some archaeologists argue that this configuration represents elements of Maya mythology: the three hearthstones of creation that were set down by the gods to create the first home and hearth, thereby civilizing humanity,” Kovacevich says. “Re-creation of that by the people at Holtun would show piousness and connection to ancestors.”

During the Classic period, kings were typically buried in Maya pyramids. During the Pre-Classic period, however, that isn’t the case and they were typically buried in their residence. It’s possible an early king of Holtun was buried in one of the residential structures, Kovacevich says.

“Ancestors are buried beneath the floor and kept very close and venerated,” she says. “The more ancestors a residence has, the more times the family redoes their floor, making a new floor, and so their mound gets higher and higher. A person with more ties, more ancestors, has more status.”

Another familiar structure is a ball court, signified by two long mounds that are exactly parallel, said Kovacevich.

“Those are the two sides of the ball court, and the ball would have been bounced in the center off of the sides,” she said. “Almost all Maya sites had a ball court.”

The team’s Holtun excavation is scheduled to start this summer. Funding is from the Institute for the Study of Earth and Man, the Downey Family Fund for Faculty Excellence and SMU. — Margaret Allen

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

Tags Brigitte Kovacevich, Dedman College, SMU Department of Anthropology

Culture, Society & Family Health & Medicine Mind & Brain Videos

Pilot study looks at women with rare Triple Negative breast cancer, which often strikes young women, minorities

Post author By Margaret Allen
Post date March 30, 2011

Pilot study looking at stress, anxiety of aggressive breast cancer striking young minorities

When an aggressive form of breast cancer strikes a young woman, what kind of stress, anxiety and other psychological and social challenges does she face?

That question hasn’t been answered in the published psychological cancer literature, but a new pilot study just launched is gathering data to change that, according to psychologist Georita M. Frierson at SMU.

The two-year study will survey up to 60 women recently diagnosed with an aggressive form of breast cancer that typically strikes younger women under 40, mostly African-American or Hispanic, or those who test positive for a mutation of the human gene that suppresses tumors, BRCA1.

Known as Triple Negative Breast Cancer, this unconventional subtype categorized as “nonhormonal” strikes 10 to 20 percent of women diagnosed with breast cancer.

The study is probing patients’ stress, anxiety and concerns about the psychological and social hurdles they face, said Frierson, principal investigator. SMU is collaborating on the Triple Negative study with the University of Texas Southwestern Simmons Cancer Center, a National Cancer Institute-designated cancer center.

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To book a live or taped interview with Dr. Georita M. Frierson in the SMU Studio call SMU News at 214-768-7650 or email news@smu.edu.

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“We don’t know anything about this population psychologically,” said Frierson, an expert in behavioral health psychology and an assistant professor in the SMU Department of Psychology. “But based on this study, for any of their concerns we could tailor a psychological intervention to help other women like the women in my pilot. These women will be our pioneers in the psychological area to help their sisters that may have Triple Negative in the future.”

For younger, minority women: Different cancer, different challenges
Triple Negative patients face far different challenges than women with traditional hormonal-type breast cancer, whose psychological and social challenges have been widely examined in the published psychological cancer literature, Frierson said. Traditional hormonal-type patients are typically over age 50, in a later career phase, raising their families, and probably have peers who may be struggling with a chronic illness.

In contrast, a Triple Negative patient is young, maybe mid-career, may not have started a family, and her peers are largely healthy and active. Because Triple Negative is a very aggressive cancer, Triple Negative patients can have lower survival rates and higher recurrence rates, and the medical treatment is different from hormonal-type cancer, Frierson said. For example, while chemotherapy can be an effective treatment for the Triple Negative patient, it can lead to short-term menopause, which may or may not be reversible, she said.

Breast cancer is the second leading cause of cancer death among women after lung cancer. In 2010, there were more than 192,300 new breast cancer cases in the United States, with more than 40,000 deaths.

The subtype is called Triple Negative because it tests negative for all three of the hormone receptors that fuel many types of breast cancer: estrogen, progesterone and human epidermal receptor 2. Some traditional breast cancer hormonal treatment therapy drugs, such as Tamoxifen, aren’t effective against Triple Negative Breast Cancer.

Results will establish protocol to develop interventions
Health care providers, social workers and others can use the study data to develop programs to reduce and manage stressors in the lives of Triple Negative patients, Frierson said.

“We want to fill a gap that needs to be addressed,” she said. “The information from this pilot can help us develop programs and support groups to ease the burden on Triple Negative survivors. When we talk about breast cancer, many people think about the woman in her 50s. But these are young cancer survivors. Really understanding those differences is important.”

Health providers who have agreed to refer patients with medical approval by their physicians include: U.T. Southwestern and Parkland Hospital in Dallas; and Moncrief Cancer Institute in Fort Worth. As a partner in the study, The Cooper Institute in Dallas will provide participants with fitness testing. The survey is also online, so a woman outside the Dallas-Fort Worth area can answer a one-time questionnaire and participate in the study.

The survey, which takes 45 minutes to an hour to answer, asks questions about physical activity, diet, nutrition, compliance with doctor appointments, stress levels, body image, quality of life, relationships, friendships, fertility, depression, anxiety, sleep and fatigue.

The research is funded with a two-year, $50,000 grant from The Discovery Foundation, Dallas. — 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.

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

Tags Georita M. Frierson, SMU Department of Psychology

Fossils & Ruins Plants & Animals Researcher news SMU In The News Videos

WFAA: North Texan finds dinosaurs in our backyards

Post author By Margaret Allen
Post date March 22, 2011

WFAA-TV reporter Jonathan Betz has covered the flying reptile research of SMU paleontologist Timothy S. Myers and the rare discovery of the bones by amateur fossil hunter Gary Byrd. The story, North Texan finds dinosaurs in our backyards, aired March 17.

Myers identified fossilized bones discovered in Texas from a flying reptile that died 89 million years ago. The bones may be the world’s earliest occurrence of the prehistoric creature known as Pteranodon, Myers says.

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.

The specimen identified by Myers had a wing span between 12 and 13 feet, or 3.6 to 4 meters. It was discovered in a rock unit that dates to early in the Late Cretaceous.

Read the full story.

EXCERPT:

By Jonathan Betz
WFAA
Look up and you’ll see Gary Byrd on a roof. That’s where his work is.

But it’s what’s underground that fascinates him.

Every free moment, the contractor roams North Texas digging in the dirt.

“When I was a kid, we’d run up and down creeks and look for stuff, and wonder what it was,” he said. “I just kept doing it, kept finding more interesting things.”

For most of his life, the 55-year-old has scoured construction sites and creek beds for dinosaur bones.

Often, he finds just dirt and rocks. But on occasion, Byrd has unearthed some truly extraordinary finds.

His treasures are enough to fill cabinets at Southern Methodist University.

“This specimen is 89 million years old,” he boasted, displaying the rare remains of a pterosaur, an ancient flying reptile that until now, had not been thought to live in Texas.
Byrd plucked the fossilized bones out of a half-built Plano subdivision.

“Finding a fossil of this magnitude is a once-in-a-lifetime kind of find,” said SMU researcher Timothy Myers. “A lot of paleontologists would probably go their entire careers without finding something this significant.”

And that’s not all. Byrd has even discovered a new dinosaur species, a large duck-billed herbivore called Protohadros byrdi — yes, named after Bird himself, who found the remains near a highway.

“That really got me going,” he confessed.

Read the full story.

Tags Dale A. Winkler, Dedman College, Huffington Department of Earth Sciences, Louis L. Jacobs, Timothy S. Myers

Earth & Climate Fossils & Ruins Plants & Animals Slideshows Videos

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

Post author By Margaret Allen
Post date February 28, 2011

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.

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

Tags Dale A. Winkler, Dedman College, Huffington Department of Earth Sciences, Louis L. Jacobs, Timothy S. Myers

Birch mouse is now 9 million years older than previously known and migrated from Asia to North America

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Mapping of Maya’s “Holtun” site in Central Lakes region of Guatemala locates triadic pyramid, astronomical observatory, ritual ball court, residential mounds, plazas

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

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