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


First eyewitness accounts of mystery volcanic eruption
This eruption occurred just before the 1815 Tambora volcanic eruption which is famous for its impact on climate worldwide, with 1816 given memorable names such as 'Eighteen-Hundred-and-Froze-to-Death', the 'Year of the Beggar' and the 'Year Without a Summer' because of unseasonal frosts, crop failure and famine across Europe and North America.

Fall foliage season may be later, but longer on warmer Earth
The fall foliage season that prompts millions of Americans to undertake jaunts into the countryside each year could come much later and possibly last a little longer within a century, according to new research.

World population to keep growing this century, hit 11 billion by 2100
Using modern statistical tools, a new study led by the University of Washington and the United Nations finds that world population is likely to keep growing throughout the 21st century.

Study finds Great Barrier Reef is an effective wave absorber
New research has found that the Great Barrier Reef, as a whole, is a remarkably effective wave absorber, despite large gaps between the reefs.

Politics Divide Coastal Residents' Views of Environment, UNH Research Finds
From the salmon-rich waters of Southeast Alaska to the white sand beaches of Florida's Gulf Coast to Downeast Maine's lobster, lumber and tourist towns, coastal residents around the U.S. share a common characteristic: their views about coastal environments divide along political lines.

Saltmarsh recovery looks good, falls short
In some places Cape Cod's imperiled saltmarsh grasses have been making a comeback, but a new study reports that their ability to protect the coast has not returned nearly as fast as their healthy appearance would suggest.

Small algae with great potential
The single most important calcifying algae of the world's oceans is able to simultaneously adapt to rising water temperatures and ocean acidification through evolution.

Decoding Virus-Host Interactions in the Oxygen-Starved Ocean
For multicellular life-plants and animals-to thrive in the oceans, there must be enough dissolved oxygen in the water. In certain coastal areas, extreme oxygen-starvation produces "dead zones" that decimate marine fisheries and destroy food web structure.

Researchers discover new producer of crucial vitamin
New research has determined that a single group of micro-organisms may be responsible for much of the world's vitamin B12 production in the oceans, with implications for the global carbon cycle and climate change.

Study solves the bluetongue disease 'overwintering' mystery
The bluetongue virus, which causes a serious disease that costs the cattle and sheep industries in the United States an estimated $125 million annually, manages to survive the winter by reproducing in the insect that transmits it, report veterinary scientists at the University of California, Davis.
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...

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...

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...

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...

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...

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...

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...

Climate Change: Evidence, Impacts, and Choices

Climate Change: Evidence, Impacts, and Choices
by National Academies Press


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 taken...

The Thinking Person's Guide to Climate Change

The Thinking Person's Guide to Climate Change
by Robert Henson (Author)


Everybody can be a thinking person when it comes to climate change, and this book is a perfect roadmap.  Start a web search for “climate change” and the first three suggestions are “facts,” “news,” and “hoax.” The Thinking Person's Guide to Climate Change is rooted in the first, up to date on the second, and anything but the last. Produced by one of the most venerable atmospheric science organizations, it is a must-read for anyone looking for the full story on climate change.

Using global research and written with nonscientists in mind, the Guide breaks down the issues into straightforward categories: “Symptoms” covers signs such as melting ice and extreme weather, while “Science” lays out what we know and how we figured it out....

© 2014 BrightSurf.com