News / Science & Technology

Wildflowers' Disappearance May Have Doomed Ice Age Giants

FILE- Wildflowers bloom on a hill overlooking a fjord filled with icebergs near the south Greenland town of Narsaq, July 27, 2009.
FILE- Wildflowers bloom on a hill overlooking a fjord filled with icebergs near the south Greenland town of Narsaq, July 27, 2009.
Reuters
Flower power may have meant the difference between life and death for some of the extinct giants of the Ice Age, including the mighty wooly mammoth and wooly rhinoceros.
 
Scientists who studied DNA preserved in Arctic permafrost sediments and in the remains of such ancient animals have concluded that these Ice Age beasts relied heavily on the protein-rich wildflowers that once blanketed the region.
 
But dramatic Ice Age climate change caused a huge decline in these plants, leaving the Arctic covered instead in grasses and shrubs that lacked the same nutritional value and could not sustain the big herbivorous mammals, the scientists reported in the journal Nature last week.
 
The change in vegetation began roughly 25,000 years ago and ended about 10,000 years ago - a time when many of the big animals slipped into extinction, the researchers said.
 
Scientists for years have been trying to figure out what caused this mass extinction, when two-thirds of all the large-bodied mammals in the Northern Hemisphere died out.
 
“Now we have, from my perspective at least, a very credible explanation,” Eske Willerslev of the University of Copenhagen, an expert in ancient DNA who led an international team of researchers, said in a telephone interview.
 
The findings contradicted the notion that humans arriving in these regions during the Ice Age caused the mass extinction by hunting the big animals into oblivion - the so-called overkill or Blitzkrieg hypothesis.
 
“We think that the major driver [of the mass extinction] is not the humans,” Willerslev said, although he did not rule out that human hunters may have delivered the coup de grace to some species already diminished by the dwindling food supplies.
 
The Arctic region once teemed with herds of big animals, in some ways resembling an African savanna. Large plant eaters included wooly mammoths, wooly rhinos, horses, bison, reindeer and camels, with predators including hyenas, saber-toothed cats, lions and huge short-faced bears.
 
The scientists carried out a 50,000-year history of the vegetation across the Arctic in Siberia and North America.
 
They obtained 242 permafrost sediment samples from various Arctic sites and studied the feces and stomach contents from the mummified remains of Ice Age animals recovered in places like Siberia. They determined the age of the samples and analyzed the DNA.
 
While many scientists had thought the ecosystem had been grasslands and the big animals were grass eaters, this study showed it instead was dominated by a kind of plant known as forbs - essentially wildflowers.
 
“The whole Arctic ecosystem looked extremely different from today. You can imagine these enormous steppes with no trees, no shrubs, but dominated by these small flowering plants,” Willerslev said.
 
Christian Brochmann, a botanist at the Natural History Museum at the University of Oslo, said the permafrost contained “a vast, frozen DNA archive left as footprints from past ecosystems,” that could be deciphered by exploring animal and plant collections already stored in museums.

You May Like

Philippines, Muslim Rebels Try to Salvage Peace Pact

Peace process faces major setback after botched military operation to find terrorists results in bloody gunbattle between government forces, Moro Islamic Liberation Front fighters More

Republicans Expect Long, Expensive Presidential Battle

Political strategist says eventual winner will be one who can put together strongest coalition of various conservative groups that make up Republican Party More

Video New Wheelchair Is Easier to Use, Increases Mobility

Engineers have come up with a lever-operated design that makes use of easily accessible bicycle technology More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Islamic State Prisoners Talk of Curiosity, God, Regreti
X
Zana Omer
March 28, 2015 1:19 AM
Islamic State fighter, a prisoner of Kurdish YPG forces, asked his family asking for forgiveness: "I destroyed myself and I destroyed them along with me." The Syrian youth was one of two detainees who spoke to VOA’s Kurdish Service about the path they chose; their names have been changed and identifying details obscured. VOA's Zana Omer reports.
Video

Video Islamic State Prisoners Talk of Curiosity, God, Regret

Islamic State fighter, a prisoner of Kurdish YPG forces, asked his family asking for forgiveness: "I destroyed myself and I destroyed them along with me." The Syrian youth was one of two detainees who spoke to VOA’s Kurdish Service about the path they chose; their names have been changed and identifying details obscured. VOA's Zana Omer reports.
Video

Video Germanwings Findings Raise Issue of Psychological Testing for Pilots

More is being discovered about the co-pilot in the crash of Germanwings Flight 9525 in the French Alps. Investigators say he was hiding a medical condition, raising questions about the mental qualifications of pilots. VOA's Carolyn Presutti reports.
Video

Video Hi-tech Motorbike Helmet's Goal: Improve Road Safety

In cities with heavily congested traffic, people can get around much faster on a motorcycle than in a car. But a rider who is not sure of his route may have to stop to look at the map or consult a GPS. A Russian start-up company is working to make navigation easier for motorcyclists. Designers at Moscow-based LiveMap are developing a smart helmet with a built-in navigation system, head-mounted display and voice recognition. Zlatica Hoke has more.
Video

Video New Wheelchair Is Easier to Use, Increases Mobility

Traditional push-rim wheelchairs create a lot of stress for arm, shoulder and neck muscles and joints. A redesigned chair, based on readily available bicycle technology, radically increases mobility while reducing the physical effort. VOA’s George Putic reports.
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 Virginia Tavern Takes Patrons Back to Medieval Times

European martial arts are not widely practiced and are unknown by most people. A tavern in Old Town Alexandria, outside Washington, wants to change this by promoting these fighting techniques from medieval times. Through combining visual arts, martial arts and culinary arts, this tavern brings medieval history back to life. VOA's Yang Lin and Helen Wu report.
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.

VOA Blogs

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