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

Nigeria Incumbent in Tight Spot as Poll Nears

Muhammadu Buhari is running a strong challenge to Goodluck Jonathan, amid a faltering economy and Boko Haram security worries More

Video Liberia's Almost Last Ebola Patient Grateful but Still Grieving

Beatrice Yardolo tells VOA that despite her fame, life is still a struggle as she waits for government's promise of support to arrive More

Video Cambodian Land Grabs Threaten Traditional Communities

At least seven different indigenous groups in Ratanakiri depend mainly on forest products for their survival, say they face loss of their land, traditional way of life More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Liberia's Almost Last Ebola Patient Grateful but Still Grievingi
X
Benno Muchler
March 26, 2015 3:41 PM
Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Liberia's Almost Last Ebola Patient Grateful but Still Grieving

Beatrice Yardolo was to make history as Liberia’s last Ebola patient. Liberians recently started counting down 42 days, the period that has to go by without a single new infection until the World Health Organization can declare a country Ebola-free. That countdown stopped on March 20 when there was another new case of Ebola, making Yardolo’s story a reminder that Ebola is far from over. Benno Muchler reports from Monrovia.
Video

Video Cambodian Land Grabs Threaten Traditional Communities

Indigenous communities in Cambodia's Ratanakiri province say the government’s economic land concession policy is taking away their land and traditional way of life, making many fear that their identity will soon be lost. Local authorities, though, have denied this is the case. VOA's Say Mony went to investigate and filed this report, narrated by Colin Lovett.
Video

Video US, South Korea Conduct Joint Military Exercises

The Eighth U.S. Army Division and the Eighth Republic of Korea Mechanized Infantry Division put on a well orchestrated show of force for the media this week during their joint military training exercises in South Korea. VOA’s Seoul correspondent Brian Padden was there and reports the soldiers were well disciplined both in conducting a complex live fire exercise and in staying on message with the press.
Video

Video Space Program Status Disappoints 'Last Man on the Moon'

One of the films that drew big crowds last week at the annual South by Southwest festival in Austin, Texas, tells the story of the last human being to stand on the moon, U.S. astronaut Eugene Cernan. It has been 42 years since Cernan returned from the moon and he laments that no one else has gone there since. VOA’s Greg Flakus reports.
Video

Video Young Filmmakers Shine Spotlight on Giving Back

A group of student filmmakers from across the United States joined President Barack Obama at the White House this month for the second annual White House Student Film Festival. Fifteen short films were officially selected from more than 1,500 entries by students aged 6 through 18. The filmmakers and their families then joined the president and a group of celebrities for a screening of their films. VOA’s Julie Taboh reports.
Video

Video VOA Exclusive: Interview with Afghan President Ashraf Ghani

Afghan President Ashraf Ghani, during his first visit as president to Washington, gave a one-on-one interview with VOA Afghan Service reporter Said Suleiman Ashna, about his request for a change in U.S. troop levels, the threat from the Islamic State, and repairing relations with the United States and Pakistan. The interview was held at Blair House, late Sunday, in Pashto.
Video

Video California Science Center Tells Story of Dead Sea Scrolls

The ancient manuscripts were uncovered in the mid-20th century, and they are still yielding clues about life and religious beliefs in ancient Israel. As VOA's Mike O'Sullivan reports, an exhibit in Los Angeles shows how modern science is bringing the history of these ancient documents to life.
Video

Video Angelina Jolie Takes Another Bold Step

Hollywood actress and filmmaker Angelina Jolie has revealed she had her ovaries and fallopian tubes removed to lower her odds of getting cancer. Doctors say the huge publicity over her decision will help raise awareness about the importance of cancer screening. VOA’s George Putic has more

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More