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

    Native Americans Ask: What About Our Water Supply?

    They say they have been facing a dangerous water contaminant for decades - uranium – but the problem has received far less attention than water contamination by lead in Flint, Michigan

    Pakistan's President Urges Nation Not to Celebrate Valentine's Day

    Mamnoon Hussain criticizes Valentine's Day, which falls on Sunday this year, as a Western import that threatens to undermine the Islamic values of Pakistan

    Mother of IS Supporter: Son Was Peaceful, 'Role Model'

    Somali-American Abdirizak Mohamed Warsame pleaded guilty Thursday to charges of conspiring to provide material support to Islamic State militants

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    New Technology Aims to Bring Election Transparency to Ugandai
    X
    Serginho Roosblad
    February 12, 2016 9:29 PM
    A team of recent graduates from Uganda’s Makerere University has created a mobile application designed to help monitor elections and expose possible rigging. The developers say the app, called E-Poll, will make Uganda's democratic process fairer. From Kampala, VOA's Serginho Roosblad reports.
    Video

    Video New Technology Aims to Bring Election Transparency to Uganda

    A team of recent graduates from Uganda’s Makerere University has created a mobile application designed to help monitor elections and expose possible rigging. The developers say the app, called E-Poll, will make Uganda's democratic process fairer. From Kampala, VOA's Serginho Roosblad reports.
    Video

    Video Refugees in Kenya Vie to Compete in Rio Olympics

    In Kenya, refugees from other African nations are training at a special camp and competing for a limited number of slots in this year's Rio Olympics under the flag of the International Olympic Committee (IOC). As Lenny Ruvaga reports from Ngong, this is a first in Olympic history.
    Video

    Video Gateway to Mecca: Historical Old Jeddah

    Local leader Sami Nawar's family has been in the Old City of Jeddah for hundreds of years and takes us on a tour of this ancient route to Mecca, also believed to be the final resting place of Adam's wife, Eve.
    Video

    Video Two-thirds of World Faces Water Shortage

    Four billion people — or two out of every three on the planet — do not have enough water to meet their basic needs. That is far greater than previously thought, according to a new study that presents a more accurate picture of the problem. As VOA's Rosanne Skirble reports, the findings will help policymakers and the public craft solutions to address the threat.
    Video

    Video As Refugees Perish, Greek Graveyards Fill

    Aid workers on the Greek island of Lesbos say they are struggling to bury the increasing number of bodies of refugees that have been recovered or washed up ashore in recent months.  The graveyards are all full, they say, yet as tens of thousands of people clamor to get out of Syria, it is clear refugees will still be coming in record numbers. For VOA, Hamada Elrasam reports from Lesbos, Greece.
    Video

    Video Russia Bristles at NATO Expansion in E. Europe

    Russian Foreign Minister Sergei Lavrov is meeting Friday with the head of NATO after the Western military alliance and the United States announced plans for the biggest military build-up in Europe since the Cold War. Russia has called NATO's moves a threat to stability in Europe. But NATO says the troop rotations and equipment are aimed at reassuring allies concerned about Russia as VOA's Daniel Schearf reports from Moscow.
    Video

    Video To Fight Zika, Scientists Target Mosquitoes

    Mosquitoes strike again. The Zika virus outbreak is just the latest headline-grabbing epidemic carried by these biting pests, but researchers are fighting back with new ways to control them. VOA's Steve Baragona takes a look.
    Video

    Video Mosul Refugees Talk About Life Under IS

    A top U.S. intelligence official told Congress this week that a planned Iraqi-led operation to re-take the city of Mosul from Islamic State militants is unlikely to take place this year. IS took over the city in June 2014, and for the past year and a half, Mosul residents have been held captive under its rule. VOA's Zana Omar talked to some families who managed to escape. Bronwyn Benito narrates his report.
    Video

    Video Scientists Make Progress Toward Better Diabetes Treatment, Cure

    Scientists at two of the top U.S. universities say they have made significant advances in their quest to find a more efficient treatment for diabetes and eventually a cure. According to the International Diabetes Federation, the disease affects more than 370 million people worldwide. VOA’s George Putic reports.
    Video

    Video NATO to Target Migrant Smugglers

    NATO has announced plans to send warships to the Aegean Sea to target migrant smugglers in the alliance's most direct intervention so far since a wave of people began trying to reach European shores.
    Video

    Video Used Books Get a New Life on the Streets of Lagos

    Used booksellers are importing books from abroad and selling them on the streets of Africa's largest city. What‘s popular with readers may surprise you. Chris Stein reports from Lagos.
    Video

    Video After NH Primaries All Eyes on South Carolina

    After Tuesday's primary in New Hampshire, US presidential candidates swiftly turned to the next election coming up in South Carolina. The so-called “first-in-the-South” poll may help further narrow down the field of candidates. Zlatica Hoke reports.
    Video

    Video Smartphone Helps Grow Vegetables

    One day, you may be using your smartphone to grow your vegetables. A Taipei-based company has developed a farm cube — a small, enclosed ecosystem designed to grow plants indoors. The environment inside is automatically adjusted by the cube, but it can also be controlled through an app. VOA's Deborah Block has more on the gardening system.
    Video

    Video Exhibit Turns da Vinci’s Drawings Into Real Objects

    In addition to being a successful artist, Renaissance genius Leonardo da Vinci designed many practical machines, some of which are still in use today, although in different forms. But a number of his projects were never realized — until today. VOA’s George Putic reports.