Margaret Allen

Research: Fossil supervolcano discovered by SMU-led team
now part of new UNESCO Geopark

geopark“It is a rare event that geology is a catalyst of public cooperation and celebration,” says geologist and volcano expert Jim Quick, SMU’s associate vice president for research and dean of graduate studies.

The new Sesia-Val Grande Geopark is an example of just that, says Quick, whose international team in 2009 discovered a fossil supervolcano that now sits at the heart of the new geopark. The discovery sparked worldwide scientific interest and a regional geotourism industry.

Recently designated a geopark by the United Nations Educational, Scientific and Cultural Organization (UNESCO), the Sesia-Val Grande Geopark encompasses more than 80 communities in the Italian Alps.

The communities joined forces more than two years ago to promote the park’s creation, which UNESCO made official in September. The geopark spans tens of thousands of acres and has at its center the massive, 282 million-year-old fossil supervolcano.

“Sesia Valley is unique,” said Quick. “The base of the Earth’s crust is turned up on edge, exposing the volcano’s plumbing — which normally extends deep into the Earth and out of sight. The uplift was created when Africa and Europe began colliding about 30 million years ago and the crust of Italy was turned on end. We call this fossil the ‘Rosetta Stone’ for supervolcanoes because the depth to which rocks are exposed will aid scientific understanding of one of nature’s most massive and violent events and help us to link the geologic and geophysical data.”

The fossil supervolcano was discovered by Quick’s scientific team, which included scientists from Italy’s University of Trieste. The supervolcano has an unprecedented 15 miles of volcano plumbing exposed from the surface to the source of the magma deep within the Earth. Previously, the discovery record for exposed plumbing was about three miles, said Quick.

Only a handful of locations worldwide are chosen annually for UNESCO’s coveted geopark designation, which supports national geological heritage initiatives.

Written by Margaret Allen

> Read the full story at the SMU Research blog
> Visit the SMU Research and Graduate Studies homepage at smu.edu/research

Research: Depressed adolescents at risk for developing anxiety

Stock photo of pensive teenSome adolescents who suffer with symptoms of depression also may be at risk for developing anxiety, according to a new study of children’s mental health.

The study found that among youth who have symptoms of depression, the risk is most severe for those who have one or more of three risk factors, said SMU psychologist Chrystyna Kouros, who led the study.

Specifically, those who are most vulnerable are those who have a pessimistic outlook toward events and circumstances in their lives; those who have mothers with a history of an anxiety disorder; or those who report that the quality of their family relationships is poor, Kouros said.

A depressed adolescent with any one of those circumstances is more at risk for developing anxiety, the researchers found. The findings suggest that mental health professionals could target adolescents with those risk factors. Early intervention might prevent anxiety from developing, Kouros said.

“Depression or anxiety can be debilitating in itself,” said Kouros, an assistant professor of psychology in SMU’s Dedman College of Humanities and Sciences. “Combined, however, they are an even bigger threat to a child’s well-being. That’s particularly the case during adolescence, when pre-teens and teens are concerned about fitting in with their peers. Anxiety can manifest as social phobia, in which kids are afraid to interact with friends and teachers, or in school refusal, in which children try to avoid going to school.”

The findings are reported in Development and Psychopathology. The study, “Dynamic temporal relations between anxious and depressive symptoms across adolescence,” appears on the journal’s web site.

Kouros co-authored the research with psychiatrist Susanna Quasem and psychologist Judy Garber, both of Vanderbilt University. Data for the study were collected by Garber, a Vanderbilt professor of psychology and human development.

The finding was based on data from 240 children from metropolitan public schools and their mothers, all of whom were assessed annually for six years. The children were followed during the important developmental period from sixth grade through 12th grade. The study was evenly divided between boys and girls.

Consistent with previous research, the authors found also that “symptoms of anxiety were a robust predictor of subsequent elevations in depressive symptoms over time in adolescents.” That link has been known for some time, Kouros said, and the current study confirmed it.

Less well understood by researchers, however, has been the link between depressive symptoms developing further into elevated anxiety, she said.

“The current study showed that depressive symptoms were followed by elevations in anxious symptoms for a subset of youth who had mothers with a history of anxiety, reported low family relationship quality, or had a more negative attributional style,” the authors reported.

Written by Margaret Allen

> Read more at the SMU Research blog

Research: SMU students discover two new supernovae

SMU graduate student researchers have discovered two new supernovae, and their observations of these massive exploding stars will help improve the astronomical “tape measure” that scientists use to calculate the acceleration of the expansion of the universe.

A supernova discovered Wednesday, Feb. 6, 2013 exploded about 450 million years ago, said Farley Ferrante, a graduate student in the Department of Physics who made the initial observation.

The exploding star is in a relatively empty portion of the sky labeled “anonymous” in the faint constellation Canes Venatici. Home to a handful of galaxies, Canes Venatici is near the constellation Ursa Major, best known for the Big Dipper.

A second supernova discovered Tuesday, Nov. 20, 2012 exploded about 230 million years ago, said Ferrante, who made the initial observation. That exploding star is in one of the many galaxies of the Virgo constellation.

Both supernovae were spotted with the Robotic Optical Transient Search Experiment’s robotic telescope ROTSE3b, which is now operated by SMU graduate students. ROTSE3b is at the McDonald Observatory in the Davis Mountains of West Texas near Fort Davis.

The supernova that exploded about 450 million years ago is officially designated Supernova 2013X. It occurred when life on Earth consisted of creatures in the seas and oceans and along coastlines. Following naming conventions for supernovae, Supernova 2013X was nicknamed “Everest” by Govinda Dhungana, an SMU graduate student who participated in the discovery.

The supernova that exploded about 230 million years ago is officially designated Supernova 2012ha. The light from that explosion has been en route to Earth since the Triassic geologic period, when dinosaurs roamed the planet. “That’s fairly recent as these explosions go,” Ferrante said. Dhungana gave the nickname “Sherpa” to Supernova 2012ha.

Everest and Sherpa are two of about 200 supernovae discovered worldwide in a given year. Before telescopes, supernovae observations were rare — sometimes only several every few centuries, according to the scientists.

“Everest and Sherpa aren’t noteworthy for being the youngest, oldest, closest, furthest or biggest supernovae ever observed,” Ferrante said. “But both, like other supernovae of their kind, are important because they provide us with information for further science.”

Everest and Sherpa are Type 1a supernovae, the result of white dwarf explosions, said Robert Kehoe, physics professor and leader of the astronomy team in the Department of Physics.

The scientists explain that a white dwarf is a dying star that has burned up all its energy. It is about as massive as the Earth’s sun. Its core is about the size of the Earth. The core is dense, however, and one teaspoon of it weighs as much as Mount Everest, Kehoe said.

A white dwarf explodes if fusion restarts by tugging material from a nearby star, according to the scientists. The white dwarf grows to about one and a half times the size of the sun. Unable to support its weight, Kehoe said, collapse is rapid, fusion reignites and the white dwarf explodes. The result is a Type 1a supernova.

“We call these Type 1a supernovae standard candles,” Ferrante said. “Since Type 1a supernovae begin from this standard process, their intrinsic brightness is very similar. So they become a device by which scientists can measure cosmic distance. From Earth, we measure the light intensity of the exploded star. As star distances from Earth increase, their brilliance diminishes.”

While Sherpa is a standard Type 1a, Everest is peculiar. It exhibits the characteristics of a Type 1a called a 1991T, Ferrante said.

“Everest is the result of two white dwarfs that collide, then merge,” he said.

Like other Type 1a supernovae, Everest and Sherpa provide scientists with a tiny piece to the puzzle of one of the greatest mysteries of the universe: What is dark energy?

Every Type 1a supernova provides astronomers with indirect information about dark energy, which makes up 73 percent of the mass-energy in the universe. It’s theorized that dark energy explains the accelerating expansion of our universe at various epochs after the Big Bang.

“Every exploding star observed allows astronomers to more precisely calibrate the increasing speed at which our universe is expanding,” Ferrante said. “The older the explosion, the farther away, the closer it was to the Big Bang and the better it helps us understand dark energy.”

Written by Margaret Allen

> Read more from the SMU Research blog

Research: How hiding in plain sight saved the Jicarilla Apache

Book cover of 'Becoming White Clay' by B. Sunday EiseltNorth America’s Jicarilla Apache tribe cloaked themselves in trade, diplomacy, and intermarriage and nearly escaped incarceration on an American Indian reservation. How they did it has been a mystery of the historical American Southwest – until now.

“In some ways, the Jicarilla still remain invisible,” according to SMU anthropologist Sunday Eiselt.

The Jicarilla Apache, an amalgamation of nomadic tribes that in the 18th century migrated off the plains and settled in the northern Rio Grande of New Mexico, were accustomed to armed resistance, guerrilla tactics and inter-tribal warfare.

They fought alongside the Pueblo Indians in the Revolt of 1680 and later resisted Comanche raiders, sometimes as contract fighters and security guards for the Spanish and American trade caravans. Then quietly, deliberately and peacefully they slipped off the radar of Spanish colonization and U.S. Manifest Destiny until 1888, when the Jicarilla became the last Native American tribe forcibly settled on a reservation.

“This was not an accident of history,” says Eiselt. The Apache, particularly the Jicarilla, were experts at invisibility — not just physically, but also socially and economically. For example, Jicarilla warriors on raids would paint themselves during the journey to the plains with white clay to avoid detection by their enemies.

The protocol beckoned supernatural or spiritual protections to bring the warriors home safely. Just as white clay was a warrior strategy for self-preservation, it stands as a metaphor for the primary message of the book.

“By ‘becoming white clay’ in their social and economic dealings,” Eiselt contends, “the Jicarilla turned the tables on non-Indian expansion and disappeared into the cultural fabric of the Southwest’s Pueblo colonies as other Native Americans were being forced onto reservations.” The Jicarilla, without firing a shot, not only avoided confinement and even extermination for nearly two centuries, they rescued their culture from extinction.

“The Jicarilla essentially colonized the colonies,” says Eiselt, an expert on the Jicarilla. “They became invisible to government authorities because they were always on the move, they intermarried with the Pueblo and Hispanic peoples, and they established long-standing trade with them. They disappeared by becoming essential, an everyday part of the frontier society of New Mexico, which sustained Spanish, Mexican and ultimately U.S. interests.”

Encapsulation of one society within a larger, dominant or more powerful society is a phenomenon known as enclavement. As a strategy it was not new to the ancestors of the Jicarilla. In fact, enclavement may have occurred multiple times as their Athapaskan ancestors migrated from Canada to the American Southwest beginning as early as the 12th century, Eiselt says.

“Few scholars recognize how significant the Jicarilla contribution was to the survival of the traditional cultures of New Mexico,” says Eiselt, whose new book “Becoming White Clay” (University of Utah Press, 2012) is a comprehensive study of one of the longest-lived and most successful nomadic ethnic group enclaves in North America. “There hasn’t been a whole lot of research into the Jicarilla, even though they’ve always been there and their contribution to New Mexican history is almost entirely underappreciated.”

“Sunday Eiselt has produced the definitive work on Jicarilla Apache history and archaeology,” says Ronald H. Towner, University of Arizona. “She uses a strong theoretical approach to enclavement and combines history, archaeology and ethnohistory to not only describe past Jicarilla movements and cultural development throughout the Southwest, but to explain how and why Jicarilla social organization at different scales structured that development during times of warfare, removal from traditional lands and economic stress. Eiselt’s scholarship is second-to-none.”

Written by Margaret Allen

> Read the full story at the SMU Research blog

Research: SMU paleontologist identifies new Texas fossil species

A new species of coelacanth fish has been discovered in Texas. Pieces of tiny fossil skull found in Fort Worth have been identified as 100 million-year-old coelacanth bones, according to SMU paleontologist John Graf.

The coelacanth has one of the longest lineages — 400 million years — of any animal. It is the fish most closely related to vertebrates, including humans.

The SMU specimen is the first coelacanth in Texas from the Cretaceous, said Graf, who identified the fossil. The Cretaceous geologic period extended from 146 million years ago to 66 million years ago.

Graf named the new coelacanth species Reidus hilli. It is now the youngest coelacanth identified in the Lone Star State, a distinction previously belonging to a 200 million-year-old coelacanth from the TriassicReidus hilli is also the first coelacanth ever identified from the Dallas-Fort Worth area.

Coelacanth fossils have been found on every continent except Antarctica. Few have been found in Texas, said Graf, a paleontology graduate student in the Huffington Department of Earth Sciences of SMU’s Dedman College.

The coelacanth has eluded extinction for 400 million years. Scientists estimate it reached its maximum diversity during the Triassic. The fish was thought to have gone extinct about 70 million years ago. However, the fish rose to fame in 1938 after live specimens were caught off the coast of Africa. Today coelacanths can be found swimming in the depths of the Indian Ocean.

“These animals have one of the longest lineages of any vertebrates that we know,” Graf said.

The SMU specimen demonstrates there was greater diversity among coelacanths during the Cretaceous than previously known.

“What makes the coelacanth interesting is that they are literally the closest living fish to all the vertebrates that are living on land,” he said. “They share the most recent common ancestor with all of terrestrial vertebrates.”

Coelacanths have boney support in their fins, which is the predecessor to true limbs. “Boney support in the fins allows a marine vertebrate to lift itself upright off the sea floor,” Graf said, “which would eventually lead to animals being able to come up on land.”

Written by Margaret Allen

> Read the full story at the SMU Research blog

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