News / Science & Technology

Study: Plants Might Lack Traits Needed to Cope With Climate Change

Plants have evolved defenses, like dropping their leaves, to adapt to cold, harsh climates. (Simon Uribe-Convers)
Plants have evolved defenses, like dropping their leaves, to adapt to cold, harsh climates. (Simon Uribe-Convers)
Rosanne Skirble
A new study suggests that modern flowering plants, trees and agricultural crops may not have the characteristics, or the time, to respond to rapid human-induced climate change.
 
The report in Nature looks at how plants evolved to cope with cold in the past, but finds these same mechanisms may not provide the same defense against human-induced climate change.

Survival traits
 
Flowering plants lived in warm tropical climates 243 million years ago. Since then, they have spread across the planet into much harsher places. George Washington University ecologist Amy Zanne and her colleagues wanted to understand how the plants survived in a colder environment. 

  • Sunrise through an oak-hickory forest canopy at Tyson Research Center, Washington University in St. Louis, Missouri. (Jonathan Myers)
  • The leaves of a sugar maple start to yellow as winter approaches, Tyson Research Center, Washington University in St. Louis, Missouri. (Jonathan Myers)
  • An ornamental cherry tree loses its leaves in the fall at the Tidal Basin, Washington, DC. (Amy Zanne)
  • A frost covered dandelion head spreads as winter arrives at the University of Idaho Arboretum, Moscow, Idaho. (Simon Uribe-Convers)
  • A birch leaf turns a bright yellow as winter approaches, Gateway Arch, St. Louis, Missouri. (Amy Zanne)
  • Maple leaves change colors before they fall in Rock Creek Park, Washington, DC. (Amy Zanne)
  • Early winter brings out the reds and oranges on sugar maple trees at the Gateway Arch, St. Louis, Missouri, USA. (Amy Zanne)
  • Buckeye leaves emerge in the spring after the winter frost at Forest Park, St. Louis, Missouri. (Amy Zanne)
  • Newly emerged tulip poplar leaves in spring after winter frost at Joyce Kilmer Memorial Forest, Robbinsville, North Carolina. (Amy Zanne)

They identified three traits that help them do that: dropping their leaves before the winter chill, narrowing the cells that transport water from the roots to the leaves, and dying back to the ground and re-sprouting from their roots or seeds in the spring.     
 
“The next bit was, we wanted to not just look at where species are today and whether they are seeing freezing or not, but to try to understand the evolution of these characteristics and the order of the evolution of those characteristics or those traits,” Zanne said.  

Evolutionary tree

To do that, the researchers constructed the largest-ever time-scaled evolutionary tree of 32,000 plant species. They then compared the emergence of those adaptive traits with big changes in the Earth's climate to reconstruct how plants evolved with the cold as they spread across the globe. 

LISTEN: Plants Might Lack Traits Needed to Cope with Climate Change
Study: Plants Might Lack Traits Needed to Cope with Climate Change i
|| 0:00:00
...    
🔇
X

“We saw for all three of the traits, there was a really strong support for finding a shift into freezing and also a shift in the trait. And so to tough it out and deal with the cold, what they did was they made these narrower pipes so that they wouldn’t get these air bubbles that blocked the water through the stems," Zanne said. "So they could maintain that stem by keeping those small pipes.  Or what they did was they dropped their leaves. So they didn’t have to keep their leaves from year to year. Or the third thing that they did was they avoided or hid from the cold altogether by becoming herbaceous.” 

Herbaceous plants have leaves and stems that die back to the ground in winter. 
 
Zanne says one of the most significant findings was that the changes occurred even before the plants' range extended into colder environments.  
 
“So what we found was that plants before they even confronted the cold, they typically already had skinnier pipes and they already had become herbaceous," she said. "So they responded already to some other pressure. And so maybe it was a dry environment or something like that and that these characteristics, these traits were then really useful for dealing with the cold. So they went into the cold well armed to handle those cold temperatures.”  
 
Zanne and her team also plan to study plants in warm or dry environments. The study suggests that modern flowering plants, trees and agricultural crops may not have the traitsor the time neededto cope with human-induced climate change.

You May Like

Turkey's Erdogan: Women Not Equal to Men

Speaking at conference in Istanbul, President Erdogan says Islam has defined a position for women: motherhood More

Ahead of SAARC Summit, Subdued Expectations

Some regional analysts say distrust between Pakistani, Indian officials has slowed SAARC's progress over the year More

Philippines Leery of Development on Reef Reclamation in S. China Sea

Chinese land reclamation projects in area have been ongoing for years, but new satellite imagery reportedly shows China’s massive construction project More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Aung San Suu Kyi: Myanmar Opposition to Keep Pushing for Constitutional Changei
X
November 24, 2014 10:09 PM
Myanmar opposition leader Aung San Suu Kyi says she and her supporters will continue pushing to amend a constitutional clause that bars her from running for president next year. VOA's Than Lwin Htun reports from the capital Naypyitaw in this report narrated by Colin Lovett.
Video

Video Aung San Suu Kyi: Myanmar Opposition to Keep Pushing for Constitutional Change

Myanmar opposition leader Aung San Suu Kyi says she and her supporters will continue pushing to amend a constitutional clause that bars her from running for president next year. VOA's Than Lwin Htun reports from the capital Naypyitaw in this report narrated by Colin Lovett.
Video

Video Mali Attempts to Shut Down Ebola Transmission Chain

Senegal and Nigeria were able to stop small Ebola outbreaks by closely monitoring those who had contact with the sick person and quickly isolating anyone with symptoms. Mali is now scrambling to do the same. VOA’s Anne Look reports from Mali on what the country is doing to shut down the chain of transmission.
Video

Video Ukraine Marks Anniversary of Deadly 1930s Famine

During a commemoration for millions who died of starvation in Ukraine in the early 1930s, President Petro Poroshenko lashed out at Soviet-era totalitarianism for causing the deaths and accused today’s Russian-backed rebels in the east of using similar tactics. VOA’s Daniel Shearf reports from Kyiv.
Video

Video Hong Kong Protests at a Crossroads

New public opinion polls in Hong Kong indicate declining support for pro-democracy demonstrations after weeks of street protests. VOA’s Bill Ide in Guangzhou and Pros Laput in Hong Kong spoke with protesters and observers about whether demonstrators have been too aggressive in pushing for change.
Video

Video US Immigration Relief Imminent for Mixed-Status Families

Tens of thousands of undocumented immigrants in the Washington, D.C., area may benefit from a controversial presidential order announced this week. It's not a path to citizenship, as some activists hoped. But it will allow more immigrants who arrived as children or who have citizen children, to avoid deportation and work legally. VOA's Victoria Macchi talks with one young man who benefited from an earlier presidential order, and whose parents may now benefit after years of living in fear.
Video

Video New Skateboard Defies Gravity

A futuristic dream only a couple of decades ago, the hoverboard – a skateboard that floats above the ground - has finally been made possible. While still not ready for mass production, it promises to become a cool mode of transport... at least over some surfaces. VOA’s George Putic reports.
Video

Video Falling Gas Prices Impact US Oil Extraction

With the price of oil now less than $80 a barrel, motorists throughout the United States are benefiting from gas prices below $3 a gallon. But as VOA’s Kane Farabaugh reports, the decreasing price of petroleum has a downside for the hydraulic fracturing industry in the United States.
Video

Video Tensions Build on Korean Peninsula Amid Military Drills

It has been another tense week on the Korean peninsula as Pyongyang threatened to again test nuclear weapons while the U.S. and South Korean forces held joint military exercises in a show of force. VOA’s Brian Padden reports from the Kunsan Air Base in South Korea.
Video

Video Mama Sarah Obama Honored at UN Women’s Entrepreneurship Day

President Barack Obama's step-grandmother is in the United States to raise money to build a $12 million school and hospital center in Kogelo, Kenya, the birthplace of the president's father, Barack Obama, Sr. She was honored for her decades of work to aid poor Kenyans at a Women's Entrepreneurship Day at the United Nations.
Video

Video Ebola Economic Toll Stirs W. Africa Food Security Concerns

The World Bank said Wednesday that it expects the economic impact of the Ebola outbreak on the sub-Saharan economy to cost somewhere betweenf $3 billion to $4 billion - well below a previously-outlined worst-case scenario of $32 billion. Some economists, however, paint a gloomier picture - warning that the disruption to regional markets and trading is considerable. Henry Ridgwell reports from London.
Video

Video Chaos, Abuse Defy Solution in Libya

The political and security crisis in Libya is deepening, with competing governments and, according to Amnesty International, widespread human rights violations committed with impunity. VOA’s Al Pessin reports from London.
Video

Video US Hosts Record 866,000 Foreign Students

Close to 900,000 international students are studying at American universities and colleges, more than ever before. About half of them come from Asia, mostly China. The United States hosts more foreign students than any other country in the world, and its foreign student population is steadily growing. Zlatica Hoke reports.

All About America

AppleAndroid