Virginia Tech Magazine
Hok-E-News -|- Winter 2007

Virginia Tech Magazine's online feature, Hok-E-News, which is updated quarterly with Web-only content, gives Web-savvy readers more news and stories about some of the exciting things happening at the university today.

Ancestor of modern trees preserves record of ancient climate change
by Susan Trulove
About 350 million years ago, at the boundary of the Devonian and Carboniferous ages, the climate changed. There was no one around to record it, but there are nonetheless records in the rocks deposited by glaciers and in tissues preserved in fossils of ancient life.

"Events at the transition had terrific biological impact, marked by extinctions and the beginnings of new life forms," said Stephen Scheckler of Blacksburg, professor of biological sciences and geosciences at Virginia Tech. At the Geological Society of America national meeting held Oct. 22-25 in Philadelphia, he reported on evidence of climate change that he found in the fossils of the ancestors of modern trees.

"This glaciation was not widely understood until recently," Scheckler said. "It was a worldwide event. The Europeans recognize the extinctions as the Hangenburg event, documented in a black shale deposit that contains a series of fauna changes. But the eastern United States was at a tropical latitude at that time, so the flora and fauna show less impact--but it is there. It is believed to be a time of coldness because there was less diversity, but it is a subtle signal."

Scientists exploring parts of the world farther from the equator have found glacial deposits where the earth was scoured and sediment was dropped as the ice moved across Africa and Brazil. "Then glacial deposits were discovered in the former tropics. There is a widespread belt of rocks in Pennsylvania that were glacially deposited," said Scheckler, who studied fossils from New York, Pennsylvania, West Virginia, and Ohio from an age when the equator ran through New York and south through Virginia and the region was uniformly at a low elevation.

In his search for evidence of climate change, Scheckler, an authority on the earliest modern tree (Nature, April 22, 1999), looked at plants that made wood in the same way modern plants make wood. In modern trees, cambium tissue produces layers of wood cells on the inside and bark cells on the outside. The cambium moves outward as the tree grows and the kinds of cells it produces reflect seasonal dormancy induced by wet and dry or warm and cold conditions. The layers, of course, are tree rings.

In the fossil record, lignophytes--all those trees that grow like modern seed plants--also produced successive layers of wood from perennial cambium tissue "and left a permanent record," said Scheckler. "And if they did everything else the same as modern trees, maybe they responded to climate the same."

Tree rings are a response to resumption of growth after a period of dormancy. "Cessation of growth and resumption of growth leave an anatomical signal that differs between tropical and temperate dormancy," Scheckler added.

In temperate trees, cells become smaller and thicker walled before growth is stopped by cold; then the new wood cells become large and thin-walled when growth resumes. In tropical trees, the rings are subtle, with no change in cell-wall thickness and only slight changes in cell size. And the changes occur more in response to wet and dry periods, rather than cold periods, so they can happen several times a year.

Using this background from modern trees, Scheckler studied the ancient plants that had the same genetics for controlling wood growth and produced the same signatures for dormancy. He has documented that the fossil "trees" from most of the Devonian period show tropical growth rings, but those from the latest Devonian and earliest Carboniferous show growth rings that resemble those of temperate trees.

Coastal redwood
This times-200 magnification of the Coastal redwood, Sequoia sempervirens, a temperate rain forest tree from the western United States, shows the "temperate" type of growth ring.
fossil wood
This fossil wood, called Araucarioxylon (magnification 200X), is reported as coming from the Olentangy Shale of Ohio and shows the "temperate" type of growth ring.

"That plants of this time responded as modern plants would to cold supports the idea that there was a sudden chilling at the end of the Devonian," Scheckler said. "Later in the Carboniferous period, you no longer see the temperate signature rings because the glacial event went away."

Scheckler delivered his talk, "Woody plant growth as a proxy for climate change at the Devonian-Carboniferous boundary," as part of the session on the Devonian–Early Carboniferous Climate Change: Glacial Deposits and Proxy Records, during which there were other presentations on analysis of rocks and fossils from the period.

D2 takes home national design award
by Katie Gehrt

East Side Deli

D2, a recently renovated dining center at Virginia Tech, was recognized for its outstanding design in the August 2006 issue of the American School and University magazine.

The Educational Interiors Showcase features 16 categories, ranging from classrooms and laboratories to cafeterias and media centers. Five other college designs and two high school designs received the outstanding honor in the cafeteria/food-service design category.

Planned by MMM Design Group and associated firm Ricca Newmark Design, D2 was completed in August of 2004. What had previously been a run-of-the-mill cafeteria was transformed into an international marketplace. High windows with scenic views, varied ceiling heights to help define spaces and circulation paths, simple materials, color changes, and specialty lighting all contributed to the overall function and look.

"We envisioned an airy, open space with an artistic flare to take dining to another level," said Ted Faulkner, associate director of Housing and Dining Services. "In the design of D2, we wanted to incorporate cutting-edge delivery of non-traditional food items in a collegiate setting."

For the award, a jury of school administrators and members of the American Institute of Architects evaluate projects submitted by design firms, architects, and interior designers. They consider technical specifications, response to the program requirements, aesthetic characteristics, and overall presentation of materials. The winners and their clients receive national exposure through American School and University's readers, website, and thousands of school board members and administrators planning and designing interior-learning environments at facility trade shows.

The largest dining facility on campus, D2 is an all-you-care-to-eat restaurant located on the upper level of Dietrick Dining Center. Able to accommodate more than 1,100 customers, it features eight major food platforms, serving a wide variety of options including crème brûlée, regional cuisine, and grill items and an authentic Brazilian churrascaria serving an array of carved meats.

For more information about D2 and other Virginia Tech dining centers, go to For more information about American School and University's design awards, go to

Was there water on Mars long enough for the origination of life?
by Susan Trulove

Based on the lovely green rock, olivine, also known as the gemstone, peridot, a Virginia Tech graduate student has created a mineral lifetime diagram that provides a clue to when and for how long there might have been water on Mars.

Amanda Albright Olsen of Altoona, Pa., a doctoral student in geosciences at Virginia Tech, presented the research at the Geological Society of America national meeting in Philadelphia on Oct. 22-25. Virginia Tech Geosciences Professor Donald Rimstidt of Christiansburg, Va., is co-author.

Olivine, a silicate mineral rich in magnesium and iron, is found on earth in volcanic rock (basalts). It has also been spotted on Mars--most recently and in significant amounts by NASA's Mars Odyssey spacecraft (Geology, June 2005). Because life requires liquid water and because olivine dissolves in water, Olsen set out to establish how long it takes olivine to dissolve. The answer could help scientists determine if there was liquid water on Mars long enough for life to develop.

"Our goal is to produce a robust analysis of olivine dissolution that can be used to predict olivine grain lifetimes," Olsen said.

She used published information and laboratory studies to construct a baseline model and introduced controlling factors, such as pH and temperature. Since environmental factors have often resulted in slower dissolution rates in the field than in the lab, she compared her results with an analysis of olivine in natural environments by Virginia Tech Geoscience Professor Michal Kowalewski and Rimstidt (2003), who determined average mineral grain lifetimes based on radiometric dates.

Olsen and Rimstidt's conclusion is that the Martian olivine could take between slightly less than a million years to as long as many millions of years to dissolve in water. She cautions that pH is a highly controlling factor and a more precise estimate awaits information on the chemical conditions on the Mars surface.

"Amanda's research will be a tool to help others pin it down," Rimstidt said.

"Regardless of what physiochemical conditions that we postulate for early Martian history, we can now propose a scenario and ask, "Is it reasonable to expect that life could have originated in this time frame?" Olsen said.

Olsen presented the paper, "Using mineral lifetime diagrams: Predicting olivine grain lifetimes on Earth and Mars," at 10:30 a.m. on Wednesday, Oct. 25, in Pennsylvania Convention Center.

Alumnus Chris Kraft presents moon rock to College of Engineering
by Lynn Nystrom
moon rock The moon rock awarded to Kraft '44 was presented to the College of Engineering and is on permanent display in Norris Hall.
The man who led the U.S. mission to the Moon in the 1960s was honored at Virginia Tech Sept. 30 by the National Aeronautics and Space Administration (NASA) for his direction of America's space program. Dr. Christopher C. Kraft Jr., a 1944 aerospace engineering graduate of Virginia Tech, received NASA's Ambassador of Exploration Award.

Capt. John Young, former NASA astronaut, presented the award to Kraft in front of more than 100 of his prominent fellow alumni of Virginia Tech's College of Engineering. In turn, Kraft presented the award--a small sample of lunar material encased in Lucite and mounted for public display--to Richard Benson, dean of engineering, for permanent display in the college.

The moon rock awarded to Kraft is part of the 842 pounds of samples brought back to Earth during the six Apollo lunar expeditions from 1969 to 1972.

"We are deeply honored by Dr. Kraft's decision to present his award to Virginia Tech's College of Engineering for permanent display," said Benson. "There is a generation of engineers, of which I am a part, which came of age during the Mercury, Gemini, and Apollo space missions. Dr. Kraft was the face of those missions--engineering at its daring best. Dr. Kraft's extraordinary contributions to NASA are just the measurable part of his legacy. How many of those inspired teenagers in the 1960's went on to successful careers in aeronautics, microelectronics, medical devices, computer science, engineering education, and more? We'll never know the whole of his legacy, but we can safely say that few Americans have ever done so much to advance the engineering and scientific prowess of this great nation."

NASA also is presenting the Ambassador of Exploration Award, in ceremonies elsewhere, to the 38 astronauts and other key individuals who participated in the Mercury, Gemini, and Apollo space programs, for realizing America's vision of space exploration from 1961 to 1972.

A native Virginian, Kraft was born in Phoebus in 1924, two years prior to the launching of the first liquid-fueled rocket by the American physicist Robert Goddard. The influence of high school teachers led him to his choice of engineering as a profession and he selected Virginia Tech. Graduating in 1944 with a bachelor's degree in aeronautical engineering, he immediately joined the Langley Aeronautical Laboratory of the National Advisory Committee for Aeronautics (NACA), the precursor of NASA.

Kraft's career is indeed phenomenal. By October 1958, he was selected as one of the original members of the Space Task Group, the organization established to manage the Project Mercury. As NASA's director of flight operations in the 1960s, he was instrumental in the decision to land an astronaut on the moon. It was 1961 and the Russians had just sent Yuri Gagarin into space. Several weeks later, U.S. astronaut Alan Shepard completed a successful mission, spending 15 minutes in a suborbital flight directed by Kraft. Following that flight, President Kennedy challenged the country to land a man on the moon within the decade and return him safely to earth.

Kraft recalled this challenge, saying, "With all due respect to the memory of John F. Kennedy, I must tell you that I thought the man had taken leave of his senses. We had never even placed a man in orbit. And yet, here in front of television cameras beaming his message all over the world was the President of the United States committing us to a lunar landing."

Despite his reservations at the time, Kraft says NASA succeeded with the moon-landing because of the "national commitment to the cause. We had financial problems. We had people problems and we had horrible experiences to deal with . . . But the great majority of the public, the Congress, and the presidential administration we had during that time period were very supportive of the goals we had set."

After Neil Armstrong set foot on the moon, Kraft went on to lead the planning and operational control of the two sub-orbital Mercury missions through Gemini, Apollo, Skylab, and the Apollo Soyuz/test project.

He was deeply involved in the development of the Space Shuttle. During its definition and design studies, he played a vital role in the decision-making process that created the Space Shuttle program, and he determined the initial configuration of the Space Shuttle system, a new concept in space transportation. Kraft was the director of NASA's Lyndon B. Johnson Space Center in Houston, Texas, from January 1972 to August 1982.

Kraft retired from NASA in 1982. In a tribute to his career at the time, the The Roanoke Times editorialized that Kraft "probably instilled more confidence in our space program than any slick campaign could have done, because of his knowledge and ability to impart it. He knew more about all of the systems aboard our spacecraft than anyone else, and was in the unenviable position of making quick, life and death decision about the flights. He was the ultimate technical generalist. Even his name seemed perfect for the job."

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