Categories
Earth & Climate Fossils & Ruins Plants & Animals Student researchers Subfeature

Prehistoric puzzle settled: carbon dioxide link to global warming 22 million years ago

The modern link between high carbon dioxide levels and climate change didn’t appear to hold true for a time interval about 22 million years ago; but now a new study has found the link does indeed exist.

Fossil leaves from Africa have resolved a prehistoric climate puzzle — and also confirm the link between carbon dioxide in the atmosphere and global warming.

Research until now has produced a variety of results and conflicting data that have cast doubt on the link between high carbon dioxide levels and climate change for a time interval about 22 million years ago.

But a new study has found the link does indeed exist for that prehistoric time period, say researchers at Southern Methodist University, Dallas.

The finding will help scientists understand how recent and future increases in the concentration of atmospheric carbon dioxide may impact the future of our planet, say the SMU researchers.

The discovery comes from new biochemical analyses of fossil leaves from plants that grew on Earth 27 million years ago and 22 million years ago, said geologist Tekie Tesfamichael, lead scientist on the research.

The new analyses confirm research about modern climate — that global temperatures rise and fall with increases and decreases in carbon dioxide in our atmosphere — but in this case even in prehistoric times, according to the SMU-led international research team.

Carbon dioxide is a gas that is normally present in the Earth’s atmosphere, even millions of years ago. It’s dubbed a greenhouse gas because greater concentrations cause the overall temperature of Earth’s atmosphere to rise, as happens in a greenhouse with lots of sunlight.

Recently greenhouse gas increases have caused global warming, which is melting glaciers, sparking extreme weather variability and causing sea levels to rise.

The new SMU discovery that carbon dioxide behaved in the same manner millions of years ago that it does today has significant implications for the future. The finding suggests the pairing of carbon dioxide and global warming that is seen today also holds true for the future if carbon dioxide levels continue to rise as they have been, said Tesfamichael.

“The more we understand about the relationship between atmospheric carbon dioxide concentrations and global temperature in the past, the more we can plan for changes ahead,” said Tesfamichael, an SMU postdoctoral fellow in Earth Sciences.

“Previous work reported a variety of results and conflicting data about carbon dioxide concentrations at the two intervals of time that we studied,” he said. “But tighter control on the age of our fossils helped us to address whether or not atmospheric carbon dioxide concentration corresponded to warming — which itself is independently well-documented in geochemical studies of marine fossils in ocean sediments.”

The researchers reported their findings in Geology, the scientific journal of the Geological Society of America. The article is “Settling the issue of ‘decoupling’ between atmospheric carbon dioxide and global temperature: [CO2]atm reconstructions across the warming Paleogene-Neogene divide.”

Co-authors from the Roy M. Huffington Department of Earth Sciences in Dedman College are professors Bonnie Jacobs, an expert in paleobotany and paleoclimate, and Neil J. Tabor, an expert in sedimentology and sedimentary geochemistry.

Other co-authors are Lauren Michel, Tennessee Technological University; Ellen Currano, University of Wyoming; Mulugeta Feseha, Addis Ababa University; Richard Barclay, Smithsonian Institution; John Kappelman, University of Texas; and Mark Schmitz, Boise State University.

Discovery of rare, well-preserved fossil leaves enables finding
The findings were possible thanks to the rare discovery of two sites with extraordinarily well-preserved fossil leaves of flowering plants from the Ethiopian Highlands of eastern Africa.

Such well-preserved fossil leaves are a rarity, Tesfamichael said.

“Finding two sites with great preservation in the same geographic region from two important time intervals was very fortunate, as this enabled us to address the question we had about the relationship between atmospheric carbon dioxide concentration and global temperatures,” he said.

Scientists know that variations in the concentration of atmospheric carbon dioxide affect carbon fixation in leaves during photosynthesis. This causes leaves to develop anatomical and physiological changes such as the frequency and size of stomata — the pores on the surface of a leaf through which carbon passes.

Scientists can measure those attributes, among others, in fossil leaves, so that leaf fossils can be used as proxies for Earth’s atmospheric carbon dioxide history.

The sites producing the leaves for the SMU study were discovered separately in years past, but major fossil collections were produced through field work coordinated by the SMU research team and their co-authors, who have been collaborating on this project for several years.

The work has had funding from the National Science Foundation, The National Geographic Committee for Research and Exploration, the SMU Ford Fellowship Program, SMU Research Council, the Institute for the Study of Earth and Man, and the Dallas Paleontological Society Frank Crane Scholarship.

The fossils are housed permanently in the collections at the National Museum of Ethiopia in Addis Ababa. Institutional and governmental support came from the National Museum of Ethiopia, the Authority for Research and Conservation of Cultural Heritage, and Addis Ababa University.

Previous studies firmly established a temperature difference
One of the sites dates to the late Oligocene Epoch, and the other to the early Miocene.

Previous studies that measured ocean temperatures from around the world for the two intervals have firmly established a temperature difference on Earth between the two times, with one much warmer than the other. So the SMU study sought to measure the levels of carbon dioxide for the two time periods.

For the SMU analyses, fossil leaves of a single species were collected from the 27 million-year-old late Oligocene site. The leaves had been deposited during prehistoric times in the area of Chilga in northwest Ethiopia most likely at a river bank. The Earth’s climate during the late Oligocene may have been somewhat warmer than today, although glaciers were forming on Antarctica. The SMU study found carbon dioxide levels, on average, around 390 parts per million, about what it is on Earth today.

Fossil leaves of the 22 million-year-old species from the early Miocene were collected from ancient lake deposits, now a rock called shale, from the modern-day Mush Valley in central Ethiopia. The early Miocene climate at that time was warmer than the late Oligocene and likewise the SMU study found higher carbon dioxide levels. Atmospheric carbon dioxide was about 870 parts per million, double what it is on Earth today.

The SMU study confirmed a relationship between carbon dioxide and temperature during the late Oligocene and early Miocene.

Paleoclimate data can help predict our planet’s future climate
While carbon dioxide isn’t the only factor affecting Earth’s climate or global mean temperature, it is widely considered by scientists among the most significant. Much is known about climate change and global warming, but questions still remain.

“One of those is ‘What’s the sensitivity of the Earth’s temperature to carbon dioxide concentration? Is it very sensitive? Is it not so sensitive?’ Estimating temperature and carbon dioxide concentrations for times in the past can help find the answer to that question,” Jacobs said. “There’s a lot of work on paleoclimate in general, but not as much on the relationship between carbon dioxide and temperature.”

The finding is an important one.

“The amount of temperature change during this interval is approximately within the range of the temperature change that is estimated from climate models for our next century given a doubling of carbon dioxide concentration since the industrial revolution,” Jacobs said.

With the new model reaffirming the prehistoric relationship, scientists can look now at related questions, said climate change scientist Lauren Michel, who worked on the study as a post-doctoral researcher at SMU.

“Answering questions about the rate of change and which factors changed first, for example, will ultimately give a clearer picture of the Earth’s climate change patterns,” Michel said. “I think it is valuable to understand the relationship of greenhouse gases and climate factors represented in the rock record so we can have a better idea of what we can expect in the future and how we can prepare for that.”

SMU study confirms relationship that previous methods overlooked
Previous studies found little to no correlation between temperature and carbon dioxide for the late Oligocene and early Miocene. That has puzzled paleoclimate researchers for at least a decade.

“We have a good test-case scenario with these well-preserved plants from both time slices, where we know one time slice, with higher levels of carbon dioxide, was a warmer climate globally than the other,” Tesfamichael said.

“It’s been a puzzle as to why the previous methods found no relationship, or an inverse correlation,” he said. “We think it’s for lack of the well-dated proxy — such as our fossil leaves from two precise times in the same region — which deliver a reliable answer. Or, perhaps the models themselves needed improvement.”

Previous studies used methodologies that differed from the SMU study, although all methods (proxies) incorporate some aspects of what is known about living organisms and how they interact with atmospheric carbon dioxide.

Some studies rely on biochemical modeling of the relationship between single-celled marine fossils and atmospheric carbon dioxide, and others rely on the relationship between stomata and atmospheric carbon dioxide concentration observed in the living relatives of particular fossil plant species.

“Each method has its assumptions,” said Tesfamichael. “We will see if our results hold up with further studies of this time interval using the same methodology we used.” — Margaret Allen, SMU

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news SMU In The News

Australian Geographic: Secrets of leaf size revealed

New findings reveal the real reasons behind varying leaf sizes.

Australian Geographic has covered the research of SMU paleobotanist Bonnie F. Jacobs, a professor in SMU’s Roy M. Huffington Department of Earth Sciences.

Working with a global team of researchers, Jacobs and her colleagues cracked the mystery of leaf size. The research was published Sept. 1, 2017 as a cover story in Science.

The researchers from Australia, the U.K., Canada, Argentina, the United States, Estonia, Spain and China analyzed leaves from more than 7,600 species of plants over the past 20 years, then pooled and analyzed the data with new theory to create a series of equations that can predict the maximum viable leaf size anywhere in the world based on the risk of daytime overheating and night-time freezing.

The researchers will use these findings to create more accurate vegetation models. This will be used by governments to predict how vegetation will change locally and globally under climate change, and to plan for adaptation.

Jacobs contributed an extensive leaf database — research that was funded by a National Science Foundation grant. She analyzed the leaf characteristics of 880 species of modern tropical African plants, which occurred in various combinations among 30 plant communities. Jacobs measured leaves of the plant specimens at the Missouri Botanical Garden Herbarium, one of the largest archives of pressed dried plant specimens from around the world.

Jacobs is one of a handful of the world’s experts on the fossil plants of ancient Africa. As part of a team of paleontologists working there, she hunts plant and animal fossils in Ethiopia’s prolific Mush Valley, as well as elsewhere in Africa.

Read the full story.

EXCERPT:

By Karl Gruber
Australian Geographic

You may have learnt at school that leaf size depends on water availability and that they are meant to help plants avoid overheating. But a new study that looked at leaf sizes around the world found that, rather than water availability, it all boils down to temperature, both high and low.

Leaf sizes can vary by as much as 100,000 fold, with some leaves having an area of just 1 mm2 while other can have an area of up to 1 m2. But what is driving these big differences?

“The conventional explanation was that water availability and overheating were the two major limits to leaf size. But the data didn’t fit,” says Ian. “For example the tropics are both wet and hot, and leaves in cooler parts of the world are unlikely to overheat,” explained Ian Wright, from Macquarie University, who led the new study.

A key finding from the study is that for plants all around the world the main factors limiting leaf size are the risk of frosting in cold nights, which can damage leaves, and the risk of overheating during the day.

“Latitude explains 28% of variation leaf size, globally. Warm wet regions are characterised by large-leaved species, warm dry regions and cold regions by smaller-leaved species. These patterns can all be understood in relation to the energy inputs and outputs to leaves, but only if you consider both the daytime (overheating) and night-time (freezing) risks,” Wright says.

Read the full story.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news SMU In The News

BBC: Clues to why leaves come in many sizes

The huge variety of leaves in the plant kingdom has long been a source of wonder and fascination.

BBC News has covered the research of SMU paleobotanist Bonnie F. Jacobs, a professor in SMU’s Roy M. Huffington Department of Earth Sciences.

Working with a global team of researchers, Jacobs and her colleagues cracked the mystery of leaf size. The research was published Sept. 1, 2017 as a cover story in Science.

The researchers from Australia, the U.K., Canada, Argentina, the United States, Estonia, Spain and China analyzed leaves from more than 7,600 species of plants over the past 20 years, then pooled and analyzed the data with new theory to create a series of equations that can predict the maximum viable leaf size anywhere in the world based on the risk of daytime overheating and night-time freezing.

The researchers will use these findings to create more accurate vegetation models. This will be used by governments to predict how vegetation will change locally and globally under climate change, and to plan for adaptation.

Jacobs contributed an extensive leaf database — research that was funded by a National Science Foundation grant. She analyzed the leaf characteristics of 880 species of modern tropical African plants, which occurred in various combinations among 30 plant communities. Jacobs measured leaves of the plant specimens at the Missouri Botanical Garden Herbarium, one of the largest archives of pressed dried plant specimens from around the world.

Jacobs is one of a handful of the world’s experts on the fossil plants of ancient Africa. As part of a team of paleontologists working there, she hunts plant and animal fossils in Ethiopia’s prolific Mush Valley, as well as elsewhere in Africa.

Read the full story.

EXCERPT:

By Helen Briggs
BBC News

The leaves of a banana plant, for instance, are about a million times bigger than the leaves of heather.

The conventional wisdom is that leaf size is limited by the balance between how much water is available to a plant and the risk of overheating.

However, a study of more than 7,000 plant species around the world suggests the answer may be more complex.

“A banana leaf is able to be so huge because bananas naturally grow in places that are very hot and very wet,” said Ian Wright of Macquarie University in Sydney, Australia.
“Our work shows that in fact that if there’s enough water in the soil then there’s almost no limit to how large leaves can be.”

He says this is only part of the puzzle of leaf size.

“The other part is about the tendency for larger leaves to freeze at night,” Dr Wright explained.

“And, you put these two ingredients together — the risk of freezing and the risk of overheating — and this helps understand the pattern of leaf sizes you see across the entire world.”

There are hundreds of thousands of plant species on the planet, from tiny alpine plants to massive jungle palms.

Their leaves vary in area from less than 1 square millimetre to greater than 1 square metre.

Large-leaved plants predominate in tropical jungle — something that was noted as early as the 19th Century. Meanwhile, small-leaved plants thrive in arid deserts and at high latitudes.

Some decades ago, scientists realised that variability in leaf size was related to water and temperature. They proposed that the limit to leaf size was set by the risk of overheating.

Thus, when rainfall is high, plants can get away with having larger leaves.
The new research, published in the journal Science, suggests this idea applies only in certain regions of the globe.

“There were some pieces in this puzzle that were clearly missing,” Dr. Wright told BBC News.

Read the full story.

Categories
Earth & Climate Feature Fossils & Ruins Plants & Animals Researcher news

The mystery of leaf size solved by global team of scientists

A global team of researchers, including SMU paleobotanist Bonnie Jacobs, have cracked the mystery of leaf size. The research was published Sept. 1, 2017 as a cover story in Science.

SMU paleobotanist Bonnie F. Jacobs has contributed research to a major new study that provides scientists with a new tool for understanding both ancient and future climate by looking at the size of plant leaves.

Why is a banana leaf a million times bigger than a common heather leaf? Why are leaves generally much larger in tropical jungles than in temperate forests and deserts? The textbooks say it’s a balance between water availability and overheating.

But it’s not that simple, the researchers found.

The study, published in the Sept. 1, 2017 issue of Science, was led by Associate Professor Ian Wright from Macquarie University, Australia. The study’s findings reveal that in much of the world the key factor limiting the size of a plant’s leaves is the temperature at night and the risk of frost damage to leaves.

Jacobs said the implications of the study are significant for enabling scientists to either predict modern leaf size in the distant future, or to understand the climate for a locality as it may have been in the past.

“This research provides scientists with another tool for predicting future changes in vegetation, given climate change, and for describing ancient climate given fossil leaves,” said Jacobs, a professor in SMU’s Roy M. Huffington Department of Earth Sciences in the Dedman College of Humanities and Sciences.

“Now we can reliably use this as another way to look at future climate models for a specific location and predict the size of plant leaves,” she said. “Or, if we’re trying to understand what the climate was for a prehistoric site tens of millions of years ago, we can look at the plant fossils discovered in that location and describe what the climate most likely was at that time.”

Wright, Jacobs and 15 colleagues from Australia, the U.K., Canada, Argentina, the United States, Estonia, Spain and China analyzed leaves from more than 7,600 species, then pooled and analyzed the data with new theory to create a series of equations that can predict the maximum viable leaf size anywhere in the world based on the risk of daytime overheating and night-time freezing.

The researchers will use these findings to create more accurate vegetation models. This will be used by governments to predict how vegetation will change locally and globally under climate change, and to plan for adaptation.

Big data solves century-old conundrum
The iconic paintings of Henri Rousseau illustrate that when we think of steamy tropics we expect large leaves. But for scientists it’s been a century-old conundrum: why does leaf size vary with latitude – from very small near the poles to massive leaves in the tropics?

“The conventional explanation was that water availability and overheating were the two major limits to leaf size. But the data didn’t fit,” says Wright. “For example the tropics are both wet and hot, and leaves in cooler parts of the world are unlikely to overheat.”

“Our team worked both ends of the problem – observation and theory,” he says. “We used big data – measurements made on tens of thousands of leaves. By sampling across all continents, climate zones and plant types we were able to show that simple ‘rules’ seemingly operate across the world’s plant species, rules that were not apparent from previous, more limited analyses.”

Jacobs contributed an extensive leaf database she compiled about 20 years ago, funded by a National Science Foundation grant. She analyzed the leaf characteristics of 880 species of modern tropical African plants, which occurred in various combinations among 30 plant communities. Jacobs measured leaves of the plant specimens at the Missouri Botanical Garden Herbarium, one of the largest archives of pressed dried plant specimens from around the world.

She looked at all aspects of leaf shape and climate, ranging from seasonal and annual rainfall and temperature for each locale, as well as leaf shape, size, tip, base, among others. Using statistical analyses to plot the variables, she found the most prominent relationship between leaf shape and climate was that size increases with rainfall amount. Wet sites had species with larger leaves than dry sites.

Her Africa database was added to those of many other scientists who have compiled similar data for other localities around the world.

Threat of night time frost damage determines the size of a leaf
“Using our knowledge of plant function and biophysics we developed a fresh take on ‘leaf energy balance’ theory, and compared our predictions to observed leaf sizes,” Wright says.

“The most surprising result was that over much of the world the maximum size of leaves is set not by the risk of overheating, but rather by the risk of damaging frost at night. Larger leaves have thicker, insulating ‘boundary layers’ of still air that slows their ability to draw heat from their surroundings – heat that is needed to compensate for longwave energy lost to the night-time sky,” says co-author Colin Prentice from Imperial College London, who co-ordinated the mathematical modelling effort.

“International collaborations are making ecology into a predictive science at global scale,” says Emeritus Professor Mark Westoby. “At Macquarie University we’re proud to have led this networking over the past 20 years.” — Margaret Allen, SMU, and Macquarie University

By Ian Wright
Macquarie University

As a plant ecologist, I try to understand variation in plant traits (the physical, chemical and physiological properties of their tissues) and how this variation affects plant function in different ecosystems.

For this study I worked with 16 colleagues from Australia, the UK, Canada, Argentina, the US, Estonia, Spain and China to analyse leaves from more than 7,600 species. We then teamed the data with new theory to create a model that can predict the maximum viable leaf size anywhere in the world, based on the dual risks of daytime overheating and night-time freezing.

These findings will be used to improve global vegetation models, which are used to predict how vegetation will change under climate change, and also to better understand past climates from leaf fossils.

From giants to dwarfs
The world’s plant species vary enormously in the typical size of their leaves; from 1 square millimetre in desert species such as common eutaxia (Eutaxia microphylla), or in common heather (Calluna vulgaris) in Europe, to as much as 1 square metre in tropical species like Musa textilis, the Filipino banana tree.

But what is the physiological or ecological significance of all this variation in leaf size? How does it affect the way that plants “do business”, using leaves as protein-rich factories that trade water (transpiration) for carbon (photosynthesis), powered by energy from the sun?

More than a century ago, early plant ecologists such as Eugenius Warming argued that it was the high rainfall in the tropics that allowed large-leaved species to flourish there.

In the 1960s and ‘70s physicists and physiologists tackled the problem, showing that in mid-summer large leaves are more prone to overheating, requiring higher rates of “transpirational cooling” (a process akin to sweating) to avoid damage. This explained why many desert species have small leaves, and why species growing in cool, shaded understoreys (below the tree canopy) can have large leaves.

But still there were missing pieces to this puzzle. For example, the tropics are both wet and hot, and these theories predicted disadvantages for large-leafed species in hot regions. And, in any case, overheating must surely be unlikely for leaves in many cooler parts of the world.

Our research aimed to find these missing pieces. By collecting samples from all continents, climate zones and plant types, our team found simple “rules” that appear to apply to all of the world’s plant species – rules that were not apparent from previous, more limited analyses.

We found the key factors are day and night temperatures, rainfall and solar radiation (largely determined by distance from the Equator and the amount of cloud cover). The interaction of these factors means that in hot and sunny regions that are also very dry, most species have small leaves, but in hot or sunny regions that receive high rainfall, many species have large leaves. Finally, in very cold regions (e.g. at high elevation, or at high northern latitudes), most species have small leaves.

But the most surprising results emerged from teaming the new theory for leaf size, leaf temperature and water use with the global data analyses, to investigate what sets the maximum size of leaves possible at any point on the globe.

Read the author’s full essay

Categories
Culture, Society & Family Earth & Climate Economics & Statistics Energy & Matter Events Fossils & Ruins Health & Medicine Learning & Education Mind & Brain Plants & Animals Researcher news Student researchers

SMU 2015 research efforts broadly noted in a variety of ways for world-changing impact

SMU scientists and their research have a global reach that is frequently noted, beyond peer publications and media mentions.

By Margaret Allen
SMU News & Communications

It was a good year for SMU faculty and student research efforts. Here is a small sampling of public and published acknowledgements during 2015:

Simmons, Diego Roman, SMU, education

Hot topic merits open access
Taylor & Francis, publisher of the online journal Environmental Education Research, lifted its subscription-only requirement to meet demand for an article on how climate change is taught to middle-schoolers in California.

Co-author of the research was Diego Román, assistant professor in the Department of Teaching and Learning, Annette Caldwell Simmons School of Education and Human Development.

Román’s research revealed that California textbooks are teaching sixth graders that climate change is a controversial debate stemming from differing opinions, rather than a scientific conclusion based on rigorous scientific evidence.

The article, “Textbooks of doubt: Using systemic functional analysis to explore the framing of climate change in middle-school science textbooks,” published in September. The finding generated such strong interest that Taylor & Francis opened access to the article.

bichaw_v054i049.indd

Research makes the cover of Biochemistry
Drugs important in the battle against cancer were tested in a virtual lab by SMU biology professors to see how they would behave in the human cell.

A computer-generated composite image of the simulation made the Dec. 15 cover of the journal Biochemistry.

Scientific articles about discoveries from the simulation were also published in the peer review journals Biochemistry and in Pharmacology Research & Perspectives.

The researchers tested the drugs by simulating their interaction in a computer-generated model of one of the cell’s key molecular pumps — the protein P-glycoprotein, or P-gp. Outcomes of interest were then tested in the Wise-Vogel wet lab.

The ongoing research is the work of biochemists John Wise, associate professor, and Pia Vogel, professor and director of the SMU Center for Drug Discovery, Design and Delivery in Dedman College. Assisting them were a team of SMU graduate and undergraduate students.

The researchers developed the model to overcome the problem of relying on traditional static images for the structure of P-gp. The simulation makes it possible for researchers to dock nearly any drug in the protein and see how it behaves, then test those of interest in an actual lab.

To date, the researchers have run millions of compounds through the pump and have discovered some that are promising for development into pharmaceutical drugs to battle cancer.

Click here to read more about the research.

SMU, Simpson Rowe, sexual assault, video

Strong interest in research on sexual victimization
Teen girls were less likely to report being sexually victimized after learning to assertively resist unwanted sexual overtures and after practicing resistance in a realistic virtual environment, according to three professors from the SMU Department of Psychology.

The finding was reported in Behavior Therapy. The article was one of the psychology journal’s most heavily shared and mentioned articles across social media, blogs and news outlets during 2015, the publisher announced.

The study was the work of Dedman College faculty Lorelei Simpson Rowe, associate professor and Psychology Department graduate program co-director; Ernest Jouriles, professor; and Renee McDonald, SMU associate dean for research and academic affairs.

The journal’s publisher, Elsevier, temporarily has lifted its subscription requirement on the article, “Reducing Sexual Victimization Among Adolescent Girls: A Randomized Controlled Pilot Trial of My Voice, My Choice,” and has opened it to free access for three months.

Click here to read more about the research.

Consumers assume bigger price equals better quality
Even when competing firms can credibly disclose the positive attributes of their products to buyers, they may not do so.

Instead, they find it more lucrative to “signal” quality through the prices they charge, typically working on the assumption that shoppers think a high price indicates high quality. The resulting high prices hurt buyers, and may create a case for mandatory disclosure of quality through public policy.

That was a finding of the research of Dedman College’s Santanu Roy, professor, Department of Economics. Roy’s article about the research was published in February in one of the blue-ribbon journals, and the oldest, in the field, The Economic Journal.

Published by the U.K.’s Royal Economic Society, The Economic Journal is one of the founding journals of modern economics. The journal issued a media briefing about the paper, “Competition, Disclosure and Signaling,” typically reserved for academic papers of broad public interest.

The Journal of Physical Chemistry A

Chemistry research group edits special issue
Chemistry professors Dieter Cremer and Elfi Kraka, who lead SMU’s Computational and Theoretical Chemistry Group, were guest editors of a special issue of the prestigious Journal of Physical Chemistry. The issue published in March.

The Computational and Theoretical research group, called CATCO for short, is a union of computational and theoretical chemistry scientists at SMU. Their focus is research in computational chemistry, educating and training graduate and undergraduate students, disseminating and explaining results of their research to the broader public, and programming computers for the calculation of molecules and molecular aggregates.

The special issue of Physical Chemistry included 40 contributions from participants of a four-day conference in Dallas in March 2014 that was hosted by CATCO. The 25th Austin Symposium drew 108 participants from 22 different countries who, combined, presented eight plenary talks, 60 lectures and about 40 posters.

CATCO presented its research with contributions from Cremer and Kraka, as well as Marek Freindorf, research assistant professor; Wenli Zou, visiting professor; Robert Kalescky, post-doctoral fellow; and graduate students Alan Humason, Thomas Sexton, Dani Setlawan and Vytor Oliveira.

There have been more than 75 graduate students and research associates working in the CATCO group, which originally was formed at the University of Cologne, Germany, before moving to SMU in 2009.

519ca82d-6517-4df9-b5ac-26e5458882ef

Vertebrate paleontology recognized with proclamation
Dallas Mayor Mike Rawlings proclaimed Oct. 11-17, 2015 Vertebrate Paleontology week in Dallas on behalf of the Dallas City Council.

The proclamation honored the 75th Annual Meeting of the Society of Vertebrate Paleontology, which was jointly hosted by SMU’s Roy M. Huffington Department of Earth Sciences in Dedman College and the Perot Museum of Science and Nature. The conference drew to Dallas some 1,200 scientists from around the world.

Making research presentations or presenting research posters were: faculty members Bonnie Jacobs, Louis Jacobs, Michael Polcyn, Neil Tabor and Dale Winkler; adjunct research assistant professor Alisa Winkler; research staff member Kurt Ferguson; post-doctoral researchers T. Scott Myers and Lauren Michael; and graduate students Matthew Clemens, John Graf, Gary Johnson and Kate Andrzejewski.

The host committee co-chairs were Anthony Fiorillo, adjunct research professor; and Louis Jacobs, professor. Committee members included Polcyn; Christopher Strganac, graduate student; Diana Vineyard, research associate; and research professor Dale Winkler.

KERA radio reporter Kat Chow filed a report from the conference, explaining to listeners the science of vertebrate paleontology, which exposes the past, present and future of life on earth by studying fossils of animals that had backbones.

SMU earthquake scientists rock scientific journal

Modelled pressure changes caused by injection and production. (Nature Communications/SMU)
Modelled pressure changes caused by injection and production. (Nature Communications/SMU)

Findings by the SMU earthquake team reverberated across the nation with publication of their scientific article in the prestigious British interdisciplinary journal Nature, ranked as one of the world’s most cited scientific journals.

The article reported that the SMU-led seismology team found that high volumes of wastewater injection combined with saltwater extraction from natural gas wells is the most likely cause of unusually frequent earthquakes occurring in the Dallas-Fort Worth area near the small community of Azle.

The research was the work of Dedman College faculty Matthew Hornbach, associate professor of geophysics; Heather DeShon, associate professor of geophysics; Brian Stump, SMU Albritton Chair in Earth Sciences; Chris Hayward, research staff and director geophysics research program; and Beatrice Magnani, associate professor of geophysics.

The article, “Causal factors for seismicity near Azle, Texas,” published online in late April. Already the article has been downloaded nearly 6,000 times, and heavily shared on both social and conventional media. The article has achieved a ranking of 270, which puts it in the 99th percentile of 144,972 tracked articles of a similar age in all journals, and 98th percentile of 626 tracked articles of a similar age in Nature.

It has a very high impact factor for an article of its age,” said Robert Gregory, professor and chair, SMU Earth Sciences Department.

The scientific article also was entered into the record for public hearings both at the Texas Railroad Commission and the Texas House Subcommittee on Seismic Activity.

Researchers settle long-debated heritage question of “The Ancient One”

The skull of Kennewick Man and a sculpted bust by StudioEIS based on forensic facial reconstruction by sculptor Amanda Danning. (Credit: Brittany Tatchell)
The skull of Kennewick Man and a sculpted bust by StudioEIS based on forensic facial reconstruction by sculptor Amanda Danning. (Credit: Brittany Tatchell)

The research of Dedman College anthropologist and Henderson-Morrison Professor of Prehistory David Meltzer played a role in settling the long-debated and highly controversial heritage of “Kennewick Man.”

Also known as “The Ancient One,” the 8,400-year-old male skeleton discovered in Washington state has been the subject of debate for nearly two decades. Argument over his ancestry has gained him notoriety in high-profile newspaper and magazine articles, as well as making him the subject of intense scholarly study.

Officially the jurisdiction of the U.S. Army Corps of Engineers, Kennewick Man was discovered in 1996 and radiocarbon dated to 8500 years ago.

Because of his cranial shape and size he was declared not Native American but instead ‘Caucasoid,’ implying a very different population had once been in the Americas, one that was unrelated to contemporary Native Americans.

But Native Americans long have claimed Kennewick Man as theirs and had asked for repatriation of his remains for burial according to their customs.

Meltzer, collaborating with his geneticist colleague Eske Willerslev and his team at the Centre for GeoGenetics at the University of Copenhagen, in June reported the results of their analysis of the DNA of Kennewick in the prestigious British journal Nature in the scientific paper “The ancestry and affiliations of Kennewick Man.”

The results were announced at a news conference, settling the question based on first-ever DNA evidence: Kennewick Man is Native American.

The announcement garnered national and international media attention, and propelled a new push to return the skeleton to a coalition of Columbia Basin tribes. Sen. Patty Murray (D-WA) introduced the Bring the Ancient One Home Act of 2015 and Washington Gov. Jay Inslee has offered state assistance for returning the remains to Native Tribes.

Science named the Kennewick work one of its nine runners-up in the highly esteemed magazine’s annual “Breakthrough of the Year” competition.

The research article has been viewed more than 60,000 times. It has achieved a ranking of 665, which puts it in the 99th percentile of 169,466 tracked articles of a similar age in all journals, and in the 94th percentile of 958 tracked articles of a similar age in Nature.

In “Kennewick Man: coming to closure,” an article in the December issue of Antiquity, a journal of Cambridge University Press, Meltzer noted that the DNA merely confirmed what the tribes had known all along: “We are him, he is us,” said one tribal spokesman. Meltzer concludes: “We presented the DNA evidence. The tribal members gave it meaning.”

Click here to read more about the research.

Prehistoric vacuum cleaner captures singular award

Paleontologists Louis L. Jacobs, SMU, and Anthony Fiorillo, Perot Museum, have identified a new species of marine mammal from bones recovered from Unalaska, an Aleutian island in the North Pacific. (Hillsman Jackson, SMU)
Paleontologists Louis L. Jacobs, SMU, and Anthony Fiorillo, Perot Museum, have identified a new species of marine mammal from bones recovered from Unalaska, an Aleutian island in the North Pacific. (Hillsman Jackson, SMU)

Science writer Laura Geggel with Live Science named a new species of extinct marine mammal identified by two SMU paleontologists among “The 10 Strangest Animal Discoveries of 2015.”

The new species, dubbed a prehistoric hoover by London’s Daily Mail online news site, was identified by SMU paleontologist Louis L. Jacobs, a professor in the Roy M. Huffington Department of Earth Sciences, Dedman College of Humanities and Sciences, and paleontologist and SMU adjunct research professor Anthony Fiorillo, vice president of research and collections and chief curator at the Perot Museum of Nature and Science.

Jacobs and Fiorillo co-authored a study about the identification of new fossils from the oddball creature Desmostylia, discovered in the same waters where the popular “Deadliest Catch” TV show is filmed. The hippo-like creature ate like a vacuum cleaner and is a new genus and species of the only order of marine mammals ever to go extinct — surviving a mere 23 million years.

Desmostylians, every single species combined, lived in an interval between 33 million and 10 million years ago. Their strange columnar teeth and odd style of eating don’t occur in any other animal, Jacobs said.

SMU campus hosted the world’s premier physicists

The SMU Department of Physics hosted the “23rd International Workshop on Deep Inelastic Scattering and Related Subjects” from April 27-May 1, 2015. Deep Inelastic Scattering is the process of probing the quantum particles that make up our universe.

As noted by the CERN Courier — the news magazine of the CERN Laboratory in Geneva, which hosts the Large Hadron Collider, the world’s largest science experiment — more than 250 scientists from 30 countries presented more than 200 talks on a multitude of subjects relevant to experimental and theoretical research. SMU physicists presented at the conference.

The SMU organizing committee was led by Fred Olness, professor and chair of the SMU Department of Physics in Dedman College, who also gave opening and closing remarks at the conference. The committee consisted of other SMU faculty, including Jodi Cooley, associate professor; Simon Dalley, senior lecturer; Robert Kehoe, professor; Pavel Nadolsky, associate professor, who also presented progress on experiments at CERN’s Large Hadron Collider; Randy Scalise, senior lecturer; and Stephen Sekula, associate professor.

Sekula also organized a series of short talks for the public about physics and the big questions that face us as we try to understand our universe.

Click here to read more about the research.

Categories
Earth & Climate Fossils & Ruins Learning & Education Plants & Animals Researcher news SMU In The News Student researchers

Dallas Observer: SMU’s Bonnie Jacobs Is Searching for History Beyond Ancient in the Trinity River Bottoms

The history of the entire Trinity River bottoms is mainly a matter of conjecture and guesswork.

Bonnie Jacobs, Trinity Forest, Dallas Observer

The Dallas Observer has covered the research of SMU paleobotanist Bonnie Jacobs, a professor in SMU’s Roy M. Huffington Department of Earth Sciences. Jacobs is working with a team of SMU students and faculty who are collaborating with others in Dallas to understand the history of the area’s Trinity River. The Observer article published June 26 as part of the Observer’s profile of 20 of the metro area’s most interesting characters in its Dallas Observer People Issue.

Jacobs, one of a handful of the world’s experts on the fossil plants of ancient Africa, is part of a team of paleontologists hunting plant and animal fossils in Ethiopia’s prolific Mush Valley, as well as elsewhere in Africa. Most recently she and her students began working in the Trinity Forest.

Dallas Observer reporter Jim Schutze reported the news in his article “SMU’s Bonnie Jacobs Is Searching for History Beyond Ancient in the Trinity River Bottoms.”

Read the full story.

EXCERPT:

By Jim Schutze
Dallas Observer

Bonnie Jacobs studies plant fossils found in ancient rocks and deeply cored soil samples — bits of ancient leaf, specks of prehistoric pollen, other fragments that provide scientific windows into what was going on in a given spot thousands and even millions of years ago. Best known for 10 years’ work in the Mush Valley 100 miles northeast of Addis Ababa in Ethiopia, Jacobs, a professor at SMU, is now bringing her expertise to the soggy bottoms of the Trinity River in Dallas.

She and an intrepid crew of graduate students — Jewel Lipps, Shannon Hart and Hadley McPherson — are working to create a picture of the land along the Elm Fork that will show what was going on there through recorded history and back into prehistoric times. Working in the area northeast of the former Texas Stadium site, Jacobs and her team hope to come up with a real-life portrait of the land over time, showing not merely what plants were growing here but also what may have been going on in the overall environment, as reflected by changes in plant life.

As it is, the history of the entire Trinity River bottoms is mainly a matter of conjecture and guesswork. The forested area along the river from southern Dallas to the Elm Fork is often described as the largest remaining urban hardwood forest in Texas, but no one knows for sure if the Great Trinity Forest, as it is called now, existed before European settlement, or if it is in fact a product of 19th century settlement and more recent neglect.

Read the full story.

Categories
Culture, Society & Family Earth & Climate Fossils & Ruins Learning & Education Plants & Animals Researcher news Slideshows

SMU contributes fossils, expertise to new Perot Museum in ongoing scientific collaboration

From dinosaurs to sea turtles, and from technical assistance to advisory roles, SMU faculty and students, the SMU Shuler Museum, and the SMU Innovation Gymnasium have teamed with the nation’s new premier museum of nature and science in Dallas

Fossils on loan by SMU to the new Perot Museum of Nature and Science include those of animals from an ancient sea that once covered Dallas.

The fossils represent a slice of SMU’s scientific collaboration with the Perot Museum and its predecessor, the Dallas Museum of Natural History.

Items from SMU’s scientists include a 35-foot skeletal cast of the African dinosaur Malawisaurus standing sentry in the spacious glass lobby of the Perot, which opened Dec. 1 near downtown Dallas.

“The new museum building itself is an icon, but it’s also a statement by the city about taking the advances of science to the public,” said vertebrate paleontologist Louis L. Jacobs, an SMU Earth Sciences professor, who serves on the Perot Museum’s Advisory Board and Collections Committee.

Jacobs, who was ad interim director of the Dallas Museum of Natural History in 1999, led the team that discovered Malawisaurus in Africa. He provided the cast to the museum.

A 35-foot skeletal cast of the African dinosaur Malawisaurus, discovered by a team led by SMU paleontologist Louis L. Jacobs, is on display at the Perot Museum. (Image: Rich Tate, Alford Media)

“Here at SMU we train students and create new knowledge. The museum’s mission is to take the stories of science out to the general public so they can be used,” said Jacobs. “Anthony Fiorillo, Perot Museum Curator of Earth Sciences, is a world-class scientist with whom we work. We have a junction between the mission, training and knowledge we have here, infused into and enhanced by what the museum does. That’s why the museum is important to SMU and that’s why SMU is important to the museum.”

Fossils on loan are from the collection of the Shuler Museum of Paleontology in the Roy M. Huffington Department of Earth Sciences. SMU scientists provided technical expertise for exhibits and serve on the Perot Museum’s advisory committees.

Also on exhibit from SMU is a miniature unmanned autonomous helicopter designed for fighting fires that was built by SMU engineering students.

Herbivorous dinosaur is exhibited with ancient Texas plant fossils
Shuler Museum fossils can be viewed in the T. Boone Pickens Life Then and Now Hall. They include an unnamed 113 million-year-old herbivorous dinosaur discovered in 1985 at Proctor Lake southwest of Stephenville, Texas.

For perspective on that exhibit’s paleoenvironment in Texas at the time, SMU paleobotanist Bonnie F. Jacobs provided fossil wood, fossil cones, fossil leaves and images of microscopic pollen grains from the Shuler Museum. The fossils provided information used to create a model of an extinct tree to accompany the exhibit.

Fossil cones and leaves discovered in Hood County are from an extinct ancient tree, says SMU paleobotanist Bonnie F. Jacobs. (Image: SMU)

Plant fossils inform scientists of the ecological setting in which dinosaurs lived and died, said Bonnie Jacobs, an SMU associate professor in the Huffington Department. Her collaboration with the Perot’s Fiorillo, who also is an adjunct research professor of paleoecology in the SMU Earth sciences department, includes fossil plants from Alaska.

“Understanding past climate and climate change will help us understand what may happen in the future,” she said. Bonnie Jacobs is featured in a Perot Museum Career Inspirations video that is part of the permanent exhibit and also advised on the text of some exhibits.

“The world of the past is a test case for global climate models, which are computer driven,” she said. “If we can reconstruct climates of the ancient Earth accurately, then we can create better models of what may happen in the future.”

Understanding paleoclimate through fossil soils is the expertise of Neil Tabor, an SMU associate professor in the Earth Sciences Department whose Perot Museum video discusses ancient soils, environments and the biggest extinction event in Earth’s history.

Fossils date from period when D/FW was covered by ancient sea
The plant fossils are from the geologic period called the Cretaceous, from 146 million years ago to 66 million years ago. They were discovered at the prolific Jones Ranch fossil beds southwest of Fort Worth in Hood County.

At that time, the Jones Ranch — famous as the discovery site of Paluxysaurus jonesi, the state dinosaur of Texas — was not far inland from the muddy coastal shore of a vast shallow sea that a dozen years later would divide North America.

Giant fossil sea turtles were discovered in northeast Texas in 2006 by a 5-year-old girl, Preston Smith. SMU paleontologist Diana Vineyard identified the giant turtles as Toxochelys. (Image: SMU)

Other SMU fossils on loan also date from that period. They include sea turtles, as well as mosasaurs, which were ancient sea lizards that evolved flippers and streamlined bodies for life in the sea.

Stunning examples of fossil sea turtles were discovered in 2006 by a 5 year-old girl, Preston Smith, during a family outing along the North Sulphur River near Ladonia in northeast Texas. The turtles were stacked one on top of the other as if caught in sudden death 80 million years ago.

Diana Vineyard, director of administration and research associate at SMU’s Institute for the Study of Earth and Man, identified the turtles as Toxochelys while an SMU graduate student.

Also on loan from the Shuler Museum, and also identified by Vineyard, are 110-million-year-old sea turtles from the Early Cretaceous of Texas, discovered near Granbury. They represent early specimens in the transition of turtles from land and shallow marine animals to fully developed sea turtles, Vineyard said.

Exhibit includes mosasaur named for the city of Dallas

A Perot Museum exhibit includes a giant fossil sea turtle discovered in northeast Texas in 2006 by a 5-year-old girl. SMU paleontologist Diana Vineyard identified the giant turtles as Toxochelys. (Image: SMU)

Michael Polcyn, director of SMU’s Digital Earth Sciences Laboratory, put his expertise to work providing technical assistance for the museum’s Ocean Dallas marine reptile exhibit.

An expert in mosasaurs, Polcyn created digital reconstructions of Dallasaurus, named for the city of Dallas, and physically reconstructed the skeletons of Dallasaurus and another mosasaur, Tethysaurus, for the exhibit.

“The Ocean Dallas exhibit was a great opportunity to showcase the extraordinary story that the rocks in the Dallas area tell us about life in the deep past,” said Polcyn, whose mosasaur fieldwork extends from the United States to Angola.

“It was a great experience working with the museum’s creative and technical professionals on this project,” Polcyn said, “but it should be mentioned that many of the fossils in the exhibit were found by interested citizens walking the local creeks and rivers in search of these beasts, and it is they who deserve tremendous credit for bringing these finds to the public.”

Polcyn, who also is featured in a Perot Museum Career Inspirations video, created a skull reconstruction of the Perot Museum’s duck-billed dinosaur Protohadros, named by former SMU doctoral student Jason Head.

Other SMU fossils include dino footprint, croc egg and giant ammonite

The ammonite Parapuzosia, more than 3 feet in diameter and discovered in Dallas County, is on loan from SMU’s Shuler Museum to the Perot Museum.

SMU vertebrate paleontologist Dale A. Winkler, SMU research professor and director of the Shuler Museum, said other fossils on loan include:

  • a rare 110 million-year-old crocodile egg discovered with specimens of the crocodile Pachycheilosuchus trinquei west of Glen Rose. Pachycheilosuchus trinquei was named by Jack Rogers, a former SMU student. Rogers also found and identified the egg.
  • an ammonite, Parapuzosia, more than 3 feet in diameter and discovered in Dallas County.

In 2006, two SMU doctoral students assisted with excavation of the new species of dinosaur named for the museum’s namesakes, Margot and Ross Perot.

The dinosaur, Pachyrhinosaurus perotorum, was discovered by the Perot Museum’s Fiorillo and prepared by Perot Museum researcher Ronald Tykoski.

Using portable 3D laser technology, SMU scientists preserved electronically a rare 110 million-year-old fossilized dinosaur footprint from ichnospecies Eubrontes glenrosensis. The model is on display in the Perot Museum. (Image: SMU)

SMU doctoral student Christopher Strganac and former SMU doctoral student Thomas L. Adams helped dig Pachyrhinosaurus perotorum in Alaska. The only skeletal mount of its kind in the world, the 69 million-year-old skull is on display in the Life Then and Now Hall of the Perot Museum.

Also on view in the museum is a 3D cast of a dinosaur footprint that Adams and Strganac created from the laser scan of a 110 million-year-old fossilized dinosaur footprint, from ichnospecies Eubrontes glenrosensis, that was previously excavated and built into the wall of a bandstand at a Texas courthouse in the 1930s.

Another former SMU doctoral student highlighted among the exhibits is Yoshitsugu Kobayashi, who describes in a video the mentoring he received from the Perot’s Fiorillo while the two worked together in Alaska’s Denali National Park.

SMU’s Shuler Museum is named for Ellis W. Shuler, founder of the University’s geology department. Shuler was a driving force behind the precursor to the Perot Museum, the Dallas Museum of Natural History, established in 1936, said geologist James E. Brooks, SMU professor emeritus and SMU Provost emeritus. Brooks served on the Dallas Museum of Natural History’s board of directors from the 1980s until 2005.

Perot Museum presents a strong scientific face of Dallas
“Any first-rate city needs a strong public scientific face with which it’s identified,” Brooks said. “The Perot Museum is going to be that organization.”

Brooks was instrumental in the negotiations with Egypt that enabled the Dallas Museum of Natural History to bring Ramses the Great, its first major exhibit, to Dallas in 1989.

“Museums, in addition to educating children and the general public, also have the responsibility to generate new knowledge, because that makes the city a more intellectually vibrant place,” he said.

Brooks and Louis Jacobs serve on the Perot Museum’s Collections Committee, which serves in an advisory role to Perot Earth Sciences Curator Fiorillo. He and other SMU faculty and staff collaborate on field expeditions to Alaska and Mongolia.

SMU’s Innovation Gymasium contributes to Perot exhibit

Pegasus, an unmanned autonomous helicopter that can fight fires, was designed and built by Lyle Engineering students under Innovation Gymnasium Director Nathan Huntoon. (Image: SMU)

SMU’s Innovation Gymnasium is featured in an exhibit in the Texas Instruments Engineering and Innovation Hall at the Perot Museum, said Nathan R. Huntoon, director of the Innovation Gymnasium at the SMU Bobby B. Lyle School of Engineering.

Central to the Engineering and Innovation Hall exhibit is an unmanned autonomous helicopter that can fight fires, built by SMU engineering students.

The Innovation Gym enables SMU students to hone their engineering and creative skills by working on real world, design challenges. Companies, researchers and non-profits all provide real challenges for the students to develop innovative solutions, often under intense time and financial pressure.

The firefighting helicopter featured in the new museum was the first such project.

Accompanying the helicopter is a video demonstration of the helicopter fighting simulated fires, as well as a touch-screen application with interviews of Huntoon and SMU students discussing engineering and innovation.

Huntoon has been a member of the Technology Committee and the Engineering and Innovation Committee for the Perot Museum.

James Quick, a professor of Earth sciences, as well as SMU’s associate vice president for research and dean of graduate studies, applauded the establishment of the Perot Museum, the result of decades of work by many people.

“Every great urban center should have an outstanding museum of nature and science to stimulate the imaginations of people of all ages and attract them to science,” Quick said. “The contribution the Perot Museum will make to North Texas cannot be overstated.” — Margaret Allen

Follow SMUResearch.com on Twitter.

For more information, www.smuresearch.com.

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 an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

Categories
Earth & Climate Fossils & Ruins Researcher news SMU In The News Videos

National Geographic: Louis Jacobs, vertebrate paleontologist

National Geographic has launched its new Explorers web site, which includes SMU paleontologist Louis L. Jacobs.

The Explorers site acknowledges the work of the world’s scientists whose research is made possible in part through funding from National Geographic.

In a video description of the site, National Geographic explains: “In 1888 a club was formed, with a mission to explore. Today that spirit lives on in a new generation of National Geographic explorers. Innovative thinkers who redefine exploration. Living the mission and making the world a better place.”

A professor in Dedman College‘s Roy M. Huffington Department of Earth Sciences, Jacobs joined SMU’s faculty in 1983.

Currently his field projects include work in Mongolia and Angola. His book, “Lone Star Dinosaurs” (1999, Texas A&M University Press) was the basis of an exhibit at the Fort Worth Museum of Science and History that traveled the state. He consulted on the new exhibit, Mysteries of the Texas Dinosaurs, which opened in 2009.

Jacobs co-leads Projecto PaleoAngola, a collaborative international scientific research program focused on the ancient life of Angola.

Besides the discovery of the first dinosaur of Angola, the team has uncovered mosasaurs, plesiosaurs, turtles and other Cretaceous marine animals, but the aim is also to create a strong and lasting institutional and scientific collaboration that has a multiplier effect in Angolan academia.

In the laboratory, Jacobs’ research utilizes advanced imaging and stable isotope techniques to investigate paleoenvironmental, biogeographic and phylogenetic issues of the Mesozoic and Cenozoic eras.

Read the National Geographics’ Q&A with Jacobs.

EXCERPT:

What did you want to be when you were growing up?
I always wanted to be a scientist. I did not care what kind because I liked it all. Looking back, although neither of my parents was a scientist, I think they guided me when I was young and I never got off the track. I am very grateful for that.

How did you get started in your field of work?
I always liked the out-of-doors and I liked everything about animals. As a kid, we had a retired geologist as a neighbor who taught me about fossils and showed me how to tie a diamond hitch on a pack mule using a sawhorse. As an undergraduate, I was most interested in the physiology of invertebrates, such as deep-sea vent worms, which were just being discovered at the time. When I went to graduate school, I decided that the most important subject for me is evolution, the unifying concept that links disparate facts about life into a coherent whole. I studied paleontology because fossils link Earth and life, and you can hold them in your hand. I still get a thrill every time I do. I was guided in paleontology by Everett Lindsay, George Gaylord Simpson, and Edwin Harris Colbert.

What inspires you to dedicate your life to vertebrate paleontology?
There is no more all-encompassing science than paleontology because no other subject melds life and Earth in such multifaceted and grand ways. Almost every technique used to study life today, and almost every technique used to study Earth, has an application in paleontology. It is ever refreshing and always interesting because the evolution of life on Earth ultimately leads to us and to all other species living here and now. Thus, our understanding of the relationships between Earth and the life it bears is fundamentally important to our future.

What’s a normal day like for you?
Every day is a collection of new challenges.

Do you have a hero?
Every person who does the best that can be done with honor and dignity is my hero.

What has been your favorite experience in the field? The most challenging?
My favorite experience is usually the one I am having at the time. Most recently it was standing in southern Angola, my feet set on the crystalline rocks of the African continent, looking west over the fault that marked the edge of the rift valley that widened during the past 100 million years to become today’s South Atlantic Ocean. It is like being part of the most obvious icon in earth sciences, the breaking of the puzzle-like fit of South America and Africa. We, Projecto PaleoAngola, are the first paleontologists to look at the coast of Angola with “plate-tectonic eyes,” to collect beautiful fossil vertebrates in abundance, and to investigate the history of life along the shores of this growing ocean.

Read the National Geographics’ Q&A with Jacobs.

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 an SMU expert or book an SMU guest in the studio, call SMU News & Communications at 214-768-7650.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news SMU In The News

D Magazine: Bonnie Jacobs and other “Dallas Big Thinkers”

D Magazine journalist Dawn McMullan reported on the accomplishments of SMU paleobotanist Bonnie F. Jacobs in the monthly magazine’s “Dallas’ Big Thinkers” article, which published Sept. 21.

Jacobs, one of a handful of the world’s experts on the fossil plants of ancient Africa, is part of a team of paleontologists hunting plant and animal fossils in Ethiopia’s prolific Mush Valley, as well as elsewhere in Africa. Jacobs is an associate professor in SMU’s Roy M. Huffington Department of Earth Sciences.

In January Jacobs’ blogged from the field in Ethiopia for The New York Times’ “Scientist at Work” blog, which features scientists’ first-person accounts of their field work as it unfolds day-by-day.

McMullan’s D Magazine piece focuses on six of the region’s scientists who are making a difference in their scientific field: “We gave the world the microchip and the margarita machine. Here are six cool scientists whose brains are making waves,” McMullan writes.

Read the full story at D Magazine.

EXCERPT:

By Dawn McMullan
D Magazine

27-Million-Year-Old Pollen | Dr. Bonnie Jacobs
Associate professor in the Roy M. Huffington Department of Earth Sciences at SMU and blogger for the New York Times

Bonnie Jacobs’ favorite place to go as a kid was the American Museum of Natural History. She also had a thing for Egyptian artifacts. During visits to the beach, she collected snails and shells, which her mother later discovered, usually by following the smell.

“Growing up, I didn’t know the difference between paleontology and archeology,” she says. “My parents, as wonderful as they are, didn’t know the difference either.”

She eventually became a noted paleobotanist. Earlier this year, she wrote for the New York Times’ Scientist at Work blog, chronicling her work in Ethiopia, where she studies plant fossils to learn about the history of our changing climate. Her work there began years ago, when her husband, Louis Jacobs, a vertebrate paleontologist at SMU, got a job in Kenya. At the time, Jacobs was near the beginning of her Ph.D. research. This was before email. She worried about how she was going to transport boxes of manuscripts from Arizona to Africa. She worried that she wouldn’t finish her Ph.D. She even worried she wouldn’t find a good microscope.

Read the full story at D Magazine.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news SMU In The News

New York Times: A Last Look at Mush Valley

SMU paleobotanist Bonnie F. Jacobs is sharing with the public her scientific field work in Ethiopia as it happens in real time through posts filed to the New York Times’ “Scientist at Work” blog.

Jacobs, one of a handful of the world’s experts on the fossil plants of ancient Africa, is part of a team of paleontologists hunting plant and animal fossils in Ethiopia’s prolific Mush Valley. Jacobs is an associate professor in SMU’s Roy M. Huffington Department of Earth Sciences.

The Times’ “Scientist at Work” blog features scientists’ first-person accounts of their field work as it unfolds day-by-day.

Jacobs filed her first post on Dec. 27 as the scientific team she is part of arrived in Ethiopia. Her most recent — and final — post of the current field season was published Jan. 21, A Last Look at Mush Valley.

Read the full text of Jacobs’ first post Dec. 27.

EXCERPT:

Bonnie F. Jacobs, a paleobotanist at Southern Methodist University, writes from Ethiopia, where she is studying fossils of ancient plant and animal life. The current field season in the Mush Valley of Ethiopia is financed by a grant to Ellen Currano of Miami University, Ohio, from the National Geographic Society Committee on Research and Exploration.

By Bonnie F. Jacobs
Monday, Dec. 27

This winter’s field season in Ethiopia is my tenth since I began working there, and despite my experience I am filled with anticipation. Our project is a relatively new one — studying rocks and fossils from an important period of history, 22 million years ago — and the location, Mush Valley, is also somewhat new to our team (last year was our first collecting trip here).

Mush Valley is only about 160 kilometers northeast of the modern capital city, Addis Ababa, but it feels as though it could be a thousand miles away. Very little of city life intrudes into the villages of Upper and Lower Mush.

What really takes me away from it all are the rocks and fossils exposed by and alongside the Mush River. They provide us an exciting opportunity to document life, climate, landscape and atmosphere 22 million years ago. As we excavate blocks of fine-grained sediment — primarily shale — looking for clues to the past, the pivotal role played by that ancient time period is always on our mind.

Read Bonnie Jacobs’ full post from Dec. 27.

Read Jacobs’ Jan. 3 post: Eureka! A Fossil Bone, and Water Ferns to Boot

Read Jacobs’ Jan. 4 post: Evidence of Mammals and Legumes, 22 Million Years Old

Read Jacobs’ Jan. 7 post: Amid the Shales, Glimpses of an Ancient Forest

Read Jacobs’ Jan. 21 post: A Last Look at Mush Valley

Categories
Culture, Society & Family Earth & Climate Economics & Statistics Energy & Matter Fossils & Ruins Health & Medicine Learning & Education Mind & Brain Plants & Animals Researcher news Technology

2010 a year of advances for SMU scientific researchers at the vanguard of those helping civilization

From picking apart atomic particles at Switzerland’s CERN, to unraveling the mysterious past, to delving into the human psyche, SMU researchers are in the vanguard of those helping civilization understand more and live better.

With both public and private funding — and the assistance of their students — they are tackling such scientific and social problems as brain diseases, immigration, diabetes, evolution, volcanoes, panic disorders, childhood obesity, cancer, radiation, nuclear test monitoring, dark matter, the effects of drilling in the Barnett Shale, and the architecture of the universe.

The sun never sets on SMU research
Besides working in campus labs and within the Dallas-area community, SMU scientists conduct research throughout the world, including at CERN’s Large Hadron Collider, and in Angola, the Canary Islands, Mongolia, Kenya, Italy, China, the Congo Basin, Ethiopia, Mexico, the Northern Mariana Islands and South Korea.

“Research at SMU is exciting and expanding,” says Associate Vice President for Research and Dean of Graduate Studies James E. Quick, a professor in the Huffington Department of Earth Sciences. “Our projects cover a wide range of problems in basic and applied research, from the search for the Higgs particle at the Large Hadron Collider in CERN to the search for new approaches to treat serious diseases. The University looks forward to creating increasing opportunities for undergraduates to become involved as research expands at SMU.”

Funding from public and private sources
In 2009-10, SMU received $25.6 million in external funding for research, up from $16.5 million the previous year.

“Research is a business that cannot be grown without investment,” Quick says. “Funding that builds the research enterprise is an investment that will go on giving by enabling the University to attract more federal grants in future years.”

The funding came from public and private sources, including the National Science Foundation; the National Institutes of Health; the U.S. Departments of Agriculture, Defense, Education and Energy; the U.S. Geological Survey; Google.org; the Alfred P. Sloan Foundation; Texas’ own Hogg Foundation for Mental Health; and the Texas Instruments Foundation.

Worldwide, the news media are covering SMU research. See some of the coverage. Browse a sample of the research:

CERN and the origin of our universe
cern_atlas-thumb.jpgLed by Physics Professor Ryszard Stroynowski, SMU physics researchers belong to the global consortium of scientists investigating the origins of our universe by monitoring high-speed sub-atomic particle collisions at CERN, the world’s largest physics experiment.

Compounds to fight neurodegenerative diseases
Biehl%20lab%20400x300.jpg
Synthetic organic chemist and Chemistry Professor Edward Biehl leads a team developing organic compounds for possible treatment of neurodegenerative diseases such as Parkinson’s, Huntington’s and Alzheimer’s. Preliminary investigation of one compound found it was extremely potent as a strong, nontoxic neuroprotector in mice.

Hunting dark matter
Dark%20matterthumb.jpgAssistant Professor of Physics Jodi Cooley belongs to a high-profile international team of experimental particle physicists searching for elusive dark matter — believed to constitute the bulk of the matter in the universe — at an abandoned underground mine in Minnesota, and soon at an even deeper mine in Canada.

Robotic arms for injured war vets
Robotic%20hand%20thumb.jpg
Electrical Engineering Chairman and Professor Marc Christensen is director of a new $5.6 million center funded by the Department of Defense and industry. The center will develop for war veteran amputees a high-tech robotic arm with fiber-optic connectivity to the brain capable of “feeling” sensations.

Green energy from the Earth’s inner heat
Yellowstone%20thumb.jpg
The SMU Geothermal Laboratory, under Earth Sciences Professor David Blackwell, has identified and mapped U.S. geothermal resources capable of supplying a green source of commercial power generation, including resources that were much larger than expected under coal-rich West Virginia.

Exercise can be magic drug for depression and anxiety
Exercise%20for%20anxiety%20thumb.jpg
Psychologist Jasper Smits, director of the Anxiety Research and Treatment Program at SMU, says exercise can help many people with depression and anxiety disorders and should be more widely prescribed by mental health care providers.

The traditional treatments of cognitive behavioral therapy and pharmacotherapy don’t reach everyone who needs them, says Smits, an associate professor of psychology.

Virtual reality “dates” to prevent victimization
avatar%20thumb.jpg
SMU psychologists Ernest Jouriles, Renee McDonald and Lorelei Simpson have partnered with SMU Guildhall in developing an interactive video gaming environment where women on virtual-reality dates can learn and practice assertiveness skills to prevent sexual victimization.

With assertive resistance training, young women have reduced how often they are sexually victimized, the psychologists say.

Controlled drug delivery agents for diabetes
brent-sumerlin.thumb.jpgAssociate Chemistry Professor Brent Sumerlin leads a team of SMU chemistry researchers — including postdoctoral, graduate and undergraduate students — who fuse the fields of polymer, organic and biochemistries to develop novel materials with composite properties. Their research includes developing nano-scale polymer particles to deliver insulin to diabetics.

Sumerlin, associate professor of chemistry, was named a 2010-2012 Alfred P. Sloan Research Fellow, which carries a $50,000 national award to support his research.

Human speed
Usain_Bolt_Berlin%2Csmall.jpgAn expert on the locomotion of humans and other terrestrial animals, Associate Professor of Applied Physiology and Biomechanics Peter Weyand has analyzed the biomechanics of world-class athletes Usain Bolt and Oscar Pistorius. His research targets the relationships between muscle function, metabolic energy expenditure, whole body mechanics and performance.

Weyand’s research also looks at why smaller people tire faster. Finding that they have to take more steps to cover the same distance or travel at the same speed, he and other scientists derived an equation that can be used to calculate the energetic cost of walking.

Pacific Ring of Fire volcano monitoring
E_crater1%20thumb.jpgAn SMU team of earth scientists led by Professor and Research Dean James Quick works with the U.S. Geological Survey to monitor volcanoes in the Pacific Ocean’s Ring of Fire near Guam on the Northern Mariana Islands. Their research will help predict and anticipate hazards to the islands, the U.S. military and commercial jets.

The two-year, $250,000 project will use infrasound — in addition to more conventional seismic monitoring — to “listen” for signs a volcano is about to blow.

Reducing anxiety and asthma
Mueret%20thumb.jpgA system of monitoring breathing to reduce CO2 intake is proving useful for reducing the pain of chronic asthma and panic disorder in separate studies by Associate Psychology Professor Thomas Ritz and Assistant Psychology Professor Alicia Meuret.

The two have developed the four-week program to teach asthmatics and those with panic disorder how to better control their condition by changing the way they breathe.

Breast Cancer community engagement
breast%20cancer%20100x80.jpgAssistant Psychology Professor Georita Friersen is working with African-American and Hispanic women in Dallas to address the quality-of-life issues they face surrounding health care, particularly during diagnosis and treatment of breast cancer.

Friersen also examines health disparities regarding prevention and treatment of chronic diseases among medically underserved women and men.

Paleoclimate in humans’ first environment
Cenozoic%20Africa%20150x120%2C%2072dpi.jpgPaleobotanist and Associate Earth Sciences Professor Bonnie Jacobs researches ancient Africa’s vegetation to better understand the environmental and ecological context in which our ancient human ancestors and other mammals evolved.

Jacobs is part of an international team of researchers who combine independent lines of evidence from various fossil and geochemical sources to reconstruct the prehistoric climate, landscape and ecosystems of Ethiopia in particular. She also identifies and prepares flora fossil discoveries for Ethiopia’s national museum.

Ice Age humans
BwD%20Clovis%20type%20specimens%20II%20150x120px.jpg
Anthropology Professor David Meltzer explores the western Rockies of Colorado to understand the prehistoric Folsom hunters who adapted to high-elevation environments during the Ice Age.

Meltzer, a world-recognized expert on paleoIndians and early human migration from eastern continents to North America, was inducted into the National Academy of Scientists in 2009.

Understanding evolution
Cane%20rate%2C%20Uganda%2C%2020%20mya%20400x300.jpgThe research of paleontologist Alisa WInkler focuses on the systematics, paleobiogeography and paleoecology of fossil mammals, in particular rodents and rabbits.

Her study of prehistoric rodents in East Africa and Texas, such as the portion of jaw fossil pictured, is helping shed more light on human evolution.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news Slideshows

Ancient Africa mysteries: Evidence is weak for tropical rainforest 65 million years ago in Africa’s low-latitudes

Evidence is weak for tropical rainforest 65 million years ago in Africa’s low-latitudes

The landscape of Central Africa 65 million years ago was a low-elevation tropical belt, but the jury is still out on whether the region’s mammals browsed and hunted beneath the canopy of a lush rainforest.

The scientific evidence for a tropical rainforest at that time is weak and far from convincing, says paleobotanist Bonnie F. Jacobs, Southern Methodist University in Dallas.

Fossil pollen from Central and West Africa provide no definitive evidence for communities of rainforest trees at the beginning of the Cenozoic, says Jacobs, an expert in the paleobotany of Africa soon after dinosaurs had gone extinct. It was the start of the age of mammals, and Africa was largely an island continent.

Many Cenozoic mysteries remain to be solved
The rainforest mystery is characteristic of the scientific uncertainty and unknowns surrounding Africa’s ancient flora during the period called the Cenozoic.

There are large gaps in the fossil record, says Jacobs, a co-author of “A Review of the Cenozoic Vegetation History of Africa.” She is an associate professor in SMU’s Roy M. Huffington Department of Earth Sciences.

The analysis, a chapter in “Cenozoic Mammals of Africa” (University of California Press, 2010), is the first of its kind since 1978 to review and interpret the Cenozoic paleobotanical record of Africa, with paleogeographic maps showing paleobotanical site distributions through time. Jacobs co-authored the paper with Aaron D. Pan, a paleobotanist at the Fort Worth Museum of Science and History, and Christopher R. Scotese, in the Earth Sciences Department at the University of Texas at Arlington.

The 1008-page “Cenozoic Mammals of Africa” is the first scientific reference of its kind since 1978, comprising 48 chapters by 64 experts. The volume summarizes and interprets the published fossil research to date of Africa’s mammals, tectonics, geography, climate and flora of the past 65 million years.

Details sparse, but big picture emerges for past 65 million years
Paleobotanical data for Africa are generally meager and uneven for the Cenozoic, according to Jacobs and her co-authors.

In an original series of maps, they chart each Cenozoic Africa paleobotanical locale described in the published research to date. There are a mere 82 sites in all. Most of the sites date to 50 million years ago. Fewer date to 20 million, 30 million, 10 million and — perhaps most important — 2 million years ago, when the human family was evolving.

“Africa is disappointingly undersampled,” say Jacobs and her colleagues. “This vast continent, roughly three times the area of the United States, has so far been documented by only a handful of Paleogene plant and vertebrate localities, and it has a Neogene record heavily biased toward the depositional basins of the East African Rift.”

Shift from descriptive to analytic approach driven by holistic view

For a continent so important for its role in the evolution of mammals, the scarcity of plant fossil data stands in sharp contrast.

“As impressive as is the contemporary mammalian diversity of Africa, it is dwarfed by that of the Cenozoic,” write the volume’s editors, paleozoologist Lars Werdelin, the Swedish Museum of Natural History, and paleontologist William Joseph Sanders, the University of Michigan. Africa today represents 20 percent of the world’s land mass, is the only continent to occupy both the north and south temperate zones, and is home now to more than 1,100 mammalian species, they write in the introduction.

Africa’s paleobotanical record is key to a holistic understanding of ancient mammals, says H.B.S. Cooke in the preface. A mammal expert, Cooke was editor of the earlier 1978 scientific reference, “Evolution of African Mammals” (Harvard University Press).

“Most striking over the past years has been a shift in studying fossils from a largely descriptive taxonomy to a more analytical approach, including consideration of faunal associations, their distribution in time and space, and the environmental and climatic factors that prevailed and changed through time,” Cooke writes. ” … African prehistory has become more a study of paleobiology than mere paleontology.”

For images from Jacobs’ fieldwork in Africa go to SMU Research on Flickr.

More scientific exploration needed to fill gaps
Scientific exploration to learn more about Africa’s ancient vegetation is on the increase, say Jacobs and her co-authors. That should start to fill gaps in understanding, including the mystery of Africa’s palms.

While palm trees are common in wet tropical forests worldwide, that’s not the case in Africa today. Palm trees have not been found in abundance in Africa for the past 24 million years, regardless of whether the regional vegetation was forest, say the authors. Oddly, though, abundant palm samples have been found in some African locations dating between 65 million and 25 million years ago, including at Chilga in Ethiopia by Jacobs and Pan.

The implications of that difference are significant for the various endemic mammals of that time, many of which were absent by 23 million years ago, say the authors.

“We are fortunate that the sampling scale of most fossil localities is at the plant community level, and larger-scale changes took place one community at a time,” they write. “Thus, as Africa becomes better sampled, the uneven record will ultimately become a more complete narrative of dynamic change at the community and ecosystem levels.”

Funding for “Cenozoic Mammals of Africa” came from the Swedish Research Council; the University of Michigan’s College of Literature, Science, and the Arts, and the Museum of Paleontology; and the Regents of the University of California. — 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.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news SMU In The News

National Geographic: Texas pterosaur Aetodactylus Halli in the spotlight after 95 million years

National Geographic News interviewed SMU postdoctoral researcher Timothy S. Myers about the new species and genus of pterosaur he identified and named, Aetodactylus Halli.

In the April 28 article “Toothy Texas Pterosaur Found; Soared Over Dallas” reporter John Roach talked to Myers about the 95 million-year-old jaw that was discovered by Lake Worth resident Lance Hall.

The pterosaur flew over the ancient sea that used to cover much of the Dallas-Fort Worth area. A rare species of pterosaur in North America, Myers named the new flying reptile after Hall.

Others who wrote about Myers’ Aetodactylus Halli research include:

Others who published a story about the find were: American Scientist, MSNBC, FOX News, the San Diego Tribune and many others.

EXCERPT:

By John Roach
National Geographic News

Long before six flags flew over Texas, a newfound species of winged reptile
with an exceptionally toothy grin owned the skies over what is now the Lone
Star State.

The recently discovered pterosaur, dubbed Aetodactylus halli, was identified based on a 95-million-year-old lower jawbone found outside of Dallas by amateur fossil hunter Lance Hall.

The pterosaur had a relatively slender jaw filled with thin, needlelike teeth, which might have helped the creature pluck fish from the shallow sea that once covered the region, a new study says.

“It was hanging out near the ocean, and that is probably where it derived its food from,” said study leader Timothy Myers, a paleontologist at Southern Methodist University in Dallas.

By comparing the jawbone to more complete pterosaur fossils, Myers and his team think A. halli was a medium-size animal with a nine-foot (three-meter) wingspan and a short tail.

Texas’s Toothy Pterosaur a Rare Find
Pterosaurs ruled the skies from the late Triassic period, more than 200 million years ago, until dinosaurs went extinct at the end of the Cretaceous, about 65 million years ago.

Read the full story

Categories
Fossils & Ruins Plants & Animals Slideshows

Texas discovery: Rare 95 million-year-old flying reptile Aetodactylus halli is new genus, species of pterosaur

A 95 million-year-old fossilized jaw discovered in Texas has been identified as a new genus and species of flying reptile, Aetodactylus halli.

Aetodactylus halli is a pterosaur, a group of flying reptiles commonly referred to as pterodactyls.

The rare pterosaur — literally winged lizard — is one of the youngest members in the world of the pterosaur family Ornithocheiridae, says paleontologist Timothy S. Myers, who identified and named Aetodactylus halli.

The newly identified reptile is only the second ornithocheirid ever documented in North America, Myers says. He is a postdoctoral fellow in the Roy M. Huffington Department of Earth Sciences at Southern Methodist University in Dallas.

Aetodactylus halli would have soared over what is now the Dallas-Fort Worth area during the Cretaceous Period when much of the Lone Star state was under water, covered by a vast ancient sea.

Click here to view larger image of Aetodactylus halli

While rare in North America, toothed pterosaurs belonging to the Ornithocheiridae are a major component of Cretaceous pterosaur faunas elsewhere in the world, Myers says. The Texas specimen — a nearly complete mandible with most of its 54 teeth missing — is definitively younger than most other ornithocheirid specimens from Brazil, England and China, he says. It is five million years younger than the only other known North American ornithocheirid.

Myers describes the new species in the latest issue of the Journal of Vertebrate Paleontology.

Myers named the pterosaur Aetodactylus halli after Lance Hall, a member of the Dallas Paleontological Society who hunts fossils for a hobby. Hall found the specimen in 2006 in North Texas. It was embedded in a soft, powdery shale exposed by excavation of a hillside next to a highway. The site was near the city of Mansfield, southwest of Dallas and west of Joe Pool Lake. Hall donated the specimen to SMU.

Pterosaurs ruled the skies from the late Triassic, more than 200 million years ago, to the end of the Cretaceous, about 65 million years ago, when they went extinct. They represent the earliest vertebrates capable of flying.

Fossil hunter saw long row of teeth sockets
The Aetodactylus halli jaw was discovered in the geologic unit known as the Eagle Ford Group, which comprises sediments deposited in a shallow sea, Myers says. Outcrop of the Eagle Ford Group extends northward from southwestern Texas into southern Oklahoma and southwestern Arkansas.

“I was scanning the exposure and noticed what at first I thought was a piece of oyster shell spanning across a small erosion valley,” Hall recalls of the discovery. “Only about an inch or two was exposed. I almost passed it up thinking it was oyster, but realized it was more tan-colored like bone. I started uncovering it and realized it was the jaw to something — but I had no idea what. It was upside down and when I turned over the snout portion it was nothing but a long row of teeth sockets, which was very exciting.”

SMU vertebrate paleontologist Louis L. Jacobs, a dinosaur expert internationally recognized for his fossil discoveries in Texas and Africa, and SMU paleontologist Michael J. Polcyn, recognized for his expertise on the extinct marine reptiles called mosasaurs, both told Hall it was a pterosaur and an important find.

Unique jaw differs from others
The 38.4-centimeter Aetodactylus jaw originally contained 54 slender, pointed teeth, but only two remain in their sockets, Myers says. The lower teeth were evenly spaced and extended far back along the jaw, covering nearly three quarters of the length of the mandible. The upper and lower teeth interlaced when the jaws were closed.

In Aetodactylus, changes in tooth size along the jaw follow a similar pattern to those of other ornithocheirids. However, Aetodactylus differs from all other ornithocheirids in that its jaws were thin and delicate, with a maximum thickness not much greater than 1 centimeter, Myers says. But the specimen does compare favorably with Boreopterus, a related pterosaur from the Early Cretaceous of China, in terms of the number of teeth present in the lower jaw, he says.

Myers has estimated the wingspan around roughly 3 meters, or about 9 feet, indicating Aetodactylus would have been a “medium-sized” pterosaur, he says. While it’s not known how Aetodactylus died, at the time of death the reptile was flying over the sea and fell into the water, perhaps while fishing, Jacobs says.

Find hints at new diversity of pterosaurs
North American pterosaurs that date from the Cretaceous are all toothless, except for Aetodactylus and Coloborhynchus, Myers says. The thinness of the jaws, upward angle of the back half of the mandible and the lack of a pronounced expansion of the jaw tips indicate that Aetodactylus is different from other ornithocheirids and represents a new genus and species of pterosaur.

“Discovery of another ornithocheirid species in Texas hints at a diversity of pterosaurs in the Cretaceous of North America that wasn’t previously realized,” Myers says. “Aetodactylus also represents one of the final occurrences of ornithocheirids prior to the Late Cretaceous transition to pterosaur faunas that were dominated by the edentulous, or toothless, species.”

Texas now claims the only two of their kind
Hall on April 14 was presented with the Dallas Paleontological Society’s highest honor, the Lloyd Hill award. The award is named for the late Lloyd Hill, an amateur fossil hunter and longtime member of the Dallas Paleontological Society. Hill wrote the well-regarded novel The Village of Bom Jesus.

Much of Texas was once submerged under the Western Interior Seaway. The massive sea split North America from the Gulf of Mexico to the Arctic Ocean.

On shore, the terrain was flat and flowering plants were already dominating flora communities in this part of North America, according to paleobotanist Bonnie Jacobs, associate professor of Earth Sciences at SMU.

“There were still conifers and ferns as well, but mostly of the sort that had tiny needle leaves, like junipers,” says Bonnie Jacobs. “Sycamores and their relatives would have been among the flowering plants.”

The first ornithocheirid remains from North America, discovered in Fort Worth, were described by former SMU student Young-Nam Lee and donated by amateur collector Chris Wadleigh, says SMU’s Louis Jacobs.

“The ancient sea that covered Dallas provided the right conditions to preserve marine reptiles and other denizens of the deep, as well as the delicate bones of flying reptiles that fell from their flight to the water below,” says Louis Jacobs, a professor in SMU’s Huffington Department of Earth Sciences.

“The rocks and fossils here record a time not well represented elsewhere in North America,” says Louis Jacobs. “That’s why two species of ornithocheirids have been found here but nowhere else, and that’s why discoveries of other new fossils are sure to be made by Lance Hall and other fossil lovers.”

Myers’ article in the Journal of Vertebrate Paleontology is titled “A new ornithocheirid pterosaur from the Upper Cretaceous (Cenomanian-Turonian) Eagle Ford Group of Texas.”

The research was funded by SMU’s Roy M. Huffington Department of Earth Sciences and SMU’s Institute for the Study of Earth and Man.

Categories
Earth & Climate Fossils & Ruins Plants & Animals Researcher news

Ethiopian fossils define prehistoric ecosystems, human evolution, climate change

Leaf3%2Clr.jpgFor paleobotanist Bonnie Jacobs standing atop a mountain in the highlands of northwest Ethiopia, it’s as if she can see forever — or at least as far back as 30 million years ago.

Jacobs is part of an international team of researchers hunting scientific clues to Africa’s prehistoric ecosystems.

The researchers are among the first to combine independent lines of evidence from various fossil and geochemical sources to reconstruct the prehistoric climate, landscape and ecosystems of Ethiopia in particular, and tropical Africa in general for the time interval from 65 million years ago — when dinosaurs went extinct, to about 8 million years ago — when apes split from humans.

BonnieTreeMush3%2Clr.jpg
Paleobotanist Bonnie Jacobs in Ethiopia.

While it’s generally held that human life began in Africa, ironically there is little known about changes in the continent’s vegetation during the time when humans were evolving.

The team’s work also will help climate scientists trying to model future global warming by providing data from the tropics that up to now did not exist.

The multi-disciplinary team is studying fossils they’ve found near Chilga, a small region in the agricultural highlands.

Contrary to the common notion that vegetation decomposes in the tropics too quickly to supply evidence, sediments there have preserved an abundant variety of 28 million-year-old fossils. These include fruits, seeds, leaves, woods, pollen and spores, says Jacobs, an associate professor of Earth Sciences at Southern Methodist University and director of the Environmental Science and Studies Programs.

“There are lifetimes of work to be done in Africa on plant fossils alone, and certainly a lot more to be done with vertebrates as well,” says Jacobs, who’s done research in Africa since 1980 in Kenya, Tanzania and Ethiopia. “There’s not a well established record of plant fossils, so there’s no real context. It’s all new — so whatever you find is interesting.”

With the permission of the Ethiopian government, Jacobs — along with Ellen Currano, in the Department of Geology at Miami University, and paleobotanist Aaron Pan, curator of science at the Fort Worth Museum of Science and History — is now studying more than 1,600 fossil leaves the team gathered from two age-equivalent sites to understand climate, precipitation, vegetation and the physical landscape.

Jacobs is calculating precipitation and temperature estimates for the two Ethiopian sites using leaf traits for size and shape. While the rainfall estimates are statistically identical, the temperature estimates are not, an informative reflection of the method itself.

Pan has identified palm fossils, which help to address a big question about the timeframe for a decline in the presence of palm trees in Africa. He’s also calculating past climate using species composition of fossil leaves, fruit and flowers.

Morediggers%2Clr.jpg Currano is looking at insect damage on fossil leaves, to see if the insect fauna is as diverse and as specialized as expected for tropical forests. Neil Tabor, associate professor of Earth Sciences at SMU and an expert in sedimentology and isotope geochemistry, is calculating past climate using oxygen isotopes in minerals from fossil soils.

“We’re using multiple independent lines of evidence to get at climate reconstruction during this time interval for a place — the tropics of Africa — for which there were few data before,” Jacobs says. “The lower latitudes are especially poorly documented for fossils, which tell us about climate, so the tropical regions of Earth are poorly documented for past climate as well.”

The project is funded with a three-year, $322,000 grant from the National Science Foundation. Paleoanthropologists and vertebrate paleontologists from UT Austin, Washington University and the University of Michigan have studied the fossil bones that co-occur with the plants.

Questions they will address:

  • When and how did Africa’s rain forests evolve into the present day savannas and how did that impact human evolution?
  • What happened to the prehistoric lowland forest that’s been hypothesized across Africa in the tropical belt?
  • When did the Great Rift Valley’s formation divide the forest into eastern and western components, and how did the process evolve?
  • Why is there evidence of a large diversity of palm trees at 33 million years ago in Africa, but certain species are missing by 28 million years ago?
  • Why were palm trees abundant and diverse 100 million years ago in Africa and South America, but now rare in present-day Africa, while still prolific in the tropical forests of Southeast Asia, South America and Madagascar?
DanAfarWindow3%2Clr.jpg
SMU graduate student Daniel Danehy.

Jacobs will present her research in October at a seminar on “Cenozoic Evolution of African Landscapes” at Penn State. She and other members of the team will also report on the Ethiopian fossils in a Geological Society of America Topical Session called “Phanerozoic Paleoenvironmental Evolution of Africa,” which they’ve organized for the annual meeting from Oct. 18-21.

Jacobs’ research today expands on earlier work. She reported with her collaborators at the 2008 “Celebrating the International Year of Planet Earth” meeting of the Geological Society of America that palm trees were significant in Africa 28 million years ago

In a 2006 study that published in the “Botanical Journal of the Linnean Society,” Jacobs and lead author Pan reported that Chilga fossil leaves represent the earliest records of Africa’s characteristic palm genus “Hyphaene.”

The leaf fossils that Jacobs, Currano, and Pan are cataloging will be permanently housed in a new building now under construction at the National Museum of Ethiopia in Addis Ababa.

With a $21,600 supplemental grant from the National Science Foundation, cabinets for storing the plant and vertebrate fossils have been made in Ethiopia and Jacobs, Currano and Pan will return later this year to curate the collections. — Margaret Allen

Related links:
Ethiopia project home page
Bonnie Jacobs
Bonnie Jacobs’ research
Neil Tabor
Ellen Currano
Why fossils matter
Bonnie Jacobs’ guide to finding fossils
SMU Student Adventures blog: Research team in Ethiopia, 2007-2008
Roy M. Huffington Department of Earth Sciences
Dedman College of Humanities and Sciences

Categories
Earth & Climate Fossils & Ruins

Ethiopian fossils to shed light on climate change

Crew2007-2008-sm.jpgA team of researchers led by paleobotanist Bonnie Jacobs and sedimentologist Neil Tabor of Southern Methodist University returned to northwestern Ethiopia in late December 2007 to spend almost a month collecting additional plant fossils and gaining a more thorough understanding of their geological context.

In December 2006, the team collected more than 600 plant fossils, which are on loan for study in labs at SMU’s Roy M. Huffington Department of Earth Sciences in Dedman College. All told, the team has documented more than 1,500 plant fossils, hundreds of vertebrate fossils and numerous examples of ancient soils. This year they widen their search to better understand the geology, landscape, plant and animal communities, and climate of Chilga, Ethiopia, 28 million years ago.

The project, which also is training Ethiopian students in geology and paleontology, is funded by a $300,000, three-year grant from the National Science Foundation.

In this second year of the grant period, the team will collect from a fruit and seed deposit — to compare with that collected last year — sample leaves to provide information about insect plant-eaters, and explore for new fossil sites, according to Jacobs, associate professor, and Tabor, assistant professor, both in the Department of Earth Sciences.

The 2007-2008 Ethiopia crew

The project is expected to help scientists understand the world’s changing climate, by knowing about that of the past based upon plant fossils and ancient soils.

Documenting past climate at low latitudes, including in Africa, helps researchers understand global climate change. In addition, the early origins of Africa’s flora are largely a mystery. What we know comes primarily from hypotheses generated by the modern distributions of plants rather than from the fossil record.

bonnie-and-neil.jpg

Angiosperms, “flowering plants,” make up nearly all living plants in today’s tropical, subtropical and temperate regions. In Africa, little is known about how they changed and adapted between their evolutionary origins 130 million years ago and recent times. Chilga fossils provide a unique view of the Earth’s plant life 28 million years ago, and fill a gap in understanding the evolution of today’s tropical floras.

The 2006 effort focused on, CH-3, which was known to produce both plant and vertebrate fossils. Until last year, only 92 plant specimens had been collected from CH-3 and these all came from the surface. These are usually bigger, less delicate specimens because they’ve been exposed to erosion and perhaps moved from their original position in the sediment.
Bonnie Jacobs, Neil Tabor and crew

The researchers excavated into the hillside at CH-3, exposing the fossiliferous deposit and, after only eight days, collected 523 specimens — mainly fruits and seeds. Their finds included some things never seen before at Chilga, such as several flowers, some very tiny seeds, and a large fruit, all of which are still being studied.

Besides Jacobs and Tabor, the 2007 team included: SMU students Dan Danehy and Harvey Herr; John Kappelman, University of Texas at Austin; and Ellen Currano, Penn State University.

Related links:
Ethiopia project home page
Bonnie Jacobs
Bonnie Jacobs’ research
Neil Tabor
Dan Danehy
John Kappelman
Ellen Currano
Why fossils matter
Bonnie Jacobs’ guide to finding fossils
SMU Student Adventures blog: Research team in Ethiopia, 2007-2008
Roy M. Huffington Department of Earth Sciences
Dedman College of Humanities and Sciences
Mongabay.com: Climate shift in East Africa due to geology