Science Current Events | Science News | Brightsurf.com
 

Notre Dame research into oaks helps us understand climate change

August 03, 2012
Jeanne Romero-Severson, associate professor of biological sciences at the University of Notre Dame, and her collaborators, are tracking the evolution of the live oaks of eastern North America, seeking to understand how the trees adapted to climate change during glacial periods.

When the ice advanced, the oaks retreated. When the ice retreated the oaks advanced, spreading from tropical to temperate zones, up from Central America and Mexico into the Piedmont Carolinas. The researchers expect the study of live oak migrations and phylogeny will provide clues to the success of the oaks that range up into northern Ontario in Canada.

Oaks originated in southeast Asia before the continents split and migrated both east and west, but North America has far more species than other regions. Researchers have long suspected that repeated climate challenges might have led to this diversity. Previous studies have shown that the live oaks that live in Mexico cannot survive the Carolina winters. This shows that there are genetic differences between the southern live oaks and their northern descendants.

"In Mexico, live oaks do not experience repeated cycles of freezing and thawing," Romero-Severson says. "Are the live oak species that now live further north different species because of this cold tolerance? What about the live oak species that span the tropical-temperate divide? It is logical to assume there is a genetic basis for the ability to survive in those cold temperatures. With four groups of researchers working together, we can tease out how it was that oaks were able to adapt to the climate as they moved north. What were the genetic changes they underwent?"

Romero-Severson focuses on genetics and genomics of the oaks. Andrew Hipp of the Morton Arboretum in Lisle, Ill., is studying their morphological differences; Paul Manos of Duke University is studying their systematics (family trees based on DNA markers); and Jeannine Cavender-Bares of the University of Minnesota is studying their ecophysiology, including the survival of seedlings in cold temperatures. A National Science Foundation grant supports the research.

The team hypothesizes that trees in contact with relatives who could just manage to survive in the cold were able to "capture" from these relatives a few genes favorable for survival in colder climates, without retaining extensive genetic changes that would alter their morphology. Different animal species rarely hybridize in nature and when they do, the offspring are often sterile, like mules. Different forest tree species often make fertile interspecific hybrids, but the parent species remain morphologically distinct.

"It's a mystery to us how oak species can have rampant interspecies hybridization and yet maintain species distinction, but they do," Romero-Severson says. "Favorable gene combinations from one live oak species can be captured by any other live oak species." There might be an "interspecific hybrid screen," a process that retains a relatively small number of good genes that equip the species for successful northward migration, while maintaining all the other genes that determine species identity.

Identification of the genetic changes in the relatively small number of live oak species in the southeastern United States and Mexico can provide clues for study of the more extensive deciduous red and white oaks, which reach from the Caribbean into California to the west and up into Canada from the east. Eastern North America alone has more than two dozen red oak species and close to two dozen white oak species. Some regions in the southeastern United States have the highest concentration of oak species in the world.

"Our hypothesis is that the same set of genes is involved in cold tolerance in all of these species," Romero-Severson says. "We feel that we have defined the problem so carefully that what we learn from these live oaks will help us understand how evolution works, and how natural adaptation arises. Our goal is to understand the role of hybridization in the evolution of forest trees and how forest trees actually respond to rapid climate change."

Romero-Severson, who came to Notre Dame in 2003, is also part of a team of researchers from seven universities with an NSF grant to develop genomics tools for finding the genetic basis for tolerance to the introduced insects and diseases that threaten the nation's hardwood trees.

University of Notre Dame


Related Climate Change Current Events and Climate Change News Articles


No one-size-fits-all approach in a changing climate, changing land
As climate change alters habitats for birds and bees and everything in between, so too does the way humans decide to use land.

Climate Change Will Threaten Fish by Drying Out Southwest U.S. Streams, Study Predicts
Fish species native to a major Arizona watershed may lose access to important segments of their habitat by 2050 as surface water flow is reduced by the effects of climate warming, new research suggests.

Trees and shrubs invading critical grasslands, diminish cattle production
Half of the Earth's land mass is made up of rangelands, which include grasslands and savannas, yet they are being transformed at an alarming rate.

NOAA analysis reveals significant land cover changes in US coastal regions
A new NOAA nationwide analysis shows that between 1996 and 2011, 64,975 square miles in coastal regions--an area larger than the state of Wisconsin--experienced changes in land cover, including a decline in wetlands and forest cover with development a major contributing factor.

Waterloo makes public most complete Antarctic map for climate research
The University of Waterloo has unveiled a new satellite image of Antarctica, and the imagery will help scientists all over the world gain new insight into the effects of climate change.

Purdue ag economists: Shale oil 'dividend' could pay for smaller carbon footprint
Unanticipated economic benefits from the shale oil and gas boom could help offset the costs of substantially reducing the U.S.'s carbon footprint, Purdue agricultural economists say.

Why global warming is taking a break
Global warming is currently taking a break: whereas global temperatures rose drastically into the late 1990s, the global average temperature has risen only slightly since 1998 - surprising, considering scientific climate models predicted considerable warming due to rising greenhouse gas emissions.

Environment and health experts commit to actions on climate change
More than 500 delegates to the EcoHealth 2014 conference have issued a call to action to urgently and collaboratively address the impacts of climate change on the health of humans, animals and the global environment in light of the lack of a truly collective response to date.

The double threat of climate and land use change enhances risks to biodiversity
Researchers from Aarhus University, Denmark, and the University of Wisconsin-Madison, USA, have developed a new approach to measure the combined exposure of species to both climate and land use change.

Sun's activity influences natural climate change
For the first time, a research team has been able to reconstruct the solar activity at the end of the last ice age, around 20,000-10,000 years ago, by analysing trace elements in ice cores in Greenland and cave formations from China.
More Climate Change Current Events and Climate Change News Articles

Climate Change: Evidence and Causes (PDF Booklet)

Climate Change: Evidence and Causes (PDF Booklet)
by National Academies Press


Climate Change: Evidence and Causes is a jointly produced publication of The US National Academy of Sciences and The Royal Society. Written by a UK-US team of leading climate scientists and reviewed by climate scientists and others, the publication is intended as a brief, readable reference document for decision makers, policy makers, educators, and other individuals seeking authoritative information on the some of the questions that continue to be asked. Climate Change makes clear what is well-established and where understanding is still developing. It echoes and builds upon the long history of climate-related work from both national academies, as well as on the newest climate-change assessment from the United Nations' Intergovernmental Panel on Climate Change. It touches on current...

Climate Change: What the Science Tells Us

Climate Change: What the Science Tells Us
by Charles Fletcher (Author)


Fletcher's 1st edition of "Climate Change: What the Science Tells Us" places strong emphasis on the peer-reviewed literature in reporting the impacts of climate change on the ocean, terrestrial ecosystems, the water cycle, human communities, dangerous weather patterns, and potential future Earth systems. The book offers detailed discussion of greenhouse gases, oceanic and atmospheric processes, Pleistocene and Holocene paleoclimate, the human fingerprints of climate change, modeling climate, sea level rise, climate impacts on economic sectors, and dangerous weather patterns associated with climate change.Fletcher offers the first real textbook to present the science surrounding climate change at the right level for an undergraduate student. His polished writing style makes this an...

Don't Even Think About It: Why Our Brains Are Wired to Ignore Climate Change

Don't Even Think About It: Why Our Brains Are Wired to Ignore Climate Change
by George Marshall (Author)


Most of us recognize that climate change is real, and yet we do nothing to stop it. What is this psychological mechanism that allows us to know something is true but act as if it is not? George Marshall’s search for the answers brings him face to face with Nobel Prize-winning psychologists and the activists of the Texas Tea Party; the world’s leading climate scientists and the people who denounce them; liberal environmentalists and conservative evangelicals. What he discovered is that our values, assumptions, and prejudices can take on lives of their own, gaining authority as they are shared, dividing people in their wake.

With engaging stories and drawing on years of his own research, Marshall argues that the answers do not lie in the things that make us different and drive...

Reason in a Dark Time: Why the Struggle Against Climate Change Failed -- and What It Means for Our Future

Reason in a Dark Time: Why the Struggle Against Climate Change Failed -- and What It Means for Our Future
by Dale Jamieson (Author)


From the 1992 Rio Earth Summit to the 2009 Copenhagen Climate Conference there was a concerted international effort to stop climate change. Yet greenhouse gas emissions increased, atmospheric concentrations grew, and global warming became an observable fact of life.

In this book, philosopher Dale Jamieson explains what climate change is, why we have failed to stop it, and why it still matters what we do. Centered in philosophy, the volume also treats the scientific, historical, economic, and political dimensions of climate change. Our failure to prevent or even to respond significantly to climate change, Jamieson argues, reflects the impoverishment of our systems of practical reason, the paralysis of our politics, and the limits of our cognitive and affective capacities. The...

Climate Change: Picturing the Science

Climate Change: Picturing the Science
by Gavin Schmidt (Author), Joshua Wolfe (Author), Jeffrey D. Sachs (Foreword)


An unprecedented union of scientific analysis and stunning photography illustrating the effects of climate change on the global ecosystem. Going beyond the headlines, this work by leading NASA climate scientist Gavin Schmidt and master photographer Joshua Wolfe illustrates as never before the ramifications of shifting climate. Photographic spreads show retreating glaciers, sinking villages in Alaska’s tundra, and drying lakes. The text follows adventurous scientists through the ice caps at the poles to the coral reefs of the tropical seas. Marshaling data spanning centuries and continents, the book sparkles with cutting-edge research and visual records, including contributions from experts on atmospheric science, oceanography, paleoclimatology, technology, politics, and the polar...

The Climate Crisis: An Introductory Guide to Climate Change

The Climate Crisis: An Introductory Guide to Climate Change
by David Archer (Author), Stefan Rahmstorf (Author)


An incredible wealth of scientific data on global warming has been collected in the last few decades. The history of the Earth's climate has been probed by drilling into polar ice sheets and sediment layers of the oceans' vast depths, and great advances have been made in computer modeling of our climate. This book provides a concise and accessible overview of what we know about ongoing climate change and its impacts, and what we can do to confront the climate crisis. Using clear and simple graphics in full color, it lucidly highlights information contained in the Intergovernmental Panel on Climate Change reports, and brings the subject completely up-to-date with current science and policy. The book makes essential scientific information on this critical topic accessible to a broad...

This Changes Everything: Capitalism vs. The Climate

This Changes Everything: Capitalism vs. The Climate
by Naomi Klein (Author)


The most important book yet from the author of the international bestseller The Shock Doctrine, a brilliant explanation of why the climate crisis challenges us to abandon the core “free market” ideology of our time, restructure the global economy, and remake our political systems.

In short, either we embrace radical change ourselves or radical changes will be visited upon our physical world. The status quo is no longer an option.

In This Changes Everything Naomi Klein argues that climate change isn’t just another issue to be neatly filed between taxes and health care. It’s an alarm that calls us to fix an economic system that is already failing us in many ways. Klein meticulously builds the case for how massively reducing our greenhouse emissions is our best chance...

Climate Change: The Science of Global Warming and Our Energy Future

Climate Change: The Science of Global Warming and Our Energy Future
by Edmond A. Mathez (Author)


Climate Change is geared toward a variety of students and general readers who seek the real science behind global warming. Exquisitely illustrated, the text introduces the basic science underlying both the natural progress of climate change and the effect of human activity on the deteriorating health of our planet. Noted expert and author Edmond A. Mathez synthesizes the work of leading scholars in climatology and related fields, and he concludes with an extensive chapter on energy production, anchoring this volume in economic and technological realities and suggesting ways to reduce greenhouse-gas emissions. Climate Change opens with the climate system fundamentals: the workings of the atmosphere and ocean, their chemical interactions via the carbon cycle, and the scientific framework...

Climate Change: Evidence, Impacts, and Choices: Set of 3 Booklets

Climate Change: Evidence, Impacts, and Choices: Set of 3 Booklets
by Division on Earth and Life Studies (Author), National Research Council (Author)


What is climate? Climate is commonly thought of as the expected weather conditions at a given location over time. People know when they go to New York City in winter, they should take a heavy coat. When they visit the Pacific Northwest, they should take an umbrella. Climate can be measured as many geographic scales - for example, cities, countries, or the entire globe - by such statistics as average temperatures, average number of rainy days, and the frequency of droughts. Climate change refers to changes in these statistics over years, decades, or even centuries.

Enormous progress has been made in increasing our understanding of climate change and its causes, and a clearer picture of current and future impacts is emerging. Research is also shedding light on actions that might be...

The Sixth Extinction: An Unnatural History

The Sixth Extinction: An Unnatural History
by Elizabeth Kolbert (Author)


A major book about the future of the world, blending intellectual and natural history and field reporting into a powerful account of the mass extinction unfolding before our eyes Over the last half a billion years, there have been five mass extinctions, when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are currently monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs. This time around, the cataclysm is us. In The Sixth Extinction, two-time winner of the National Magazine Award and New Yorker writer Elizabeth Kolbert draws on the work of scores of researchers in half a dozen disciplines, accompanying many of them into the field: geologists who study...

© 2014 BrightSurf.com