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

    Video As Refugees Perish, Greek Graveyards Fill

    Before burial at overflowing cemeteries, unidentified dead being swapped for DNA, in case some day relatives come to learn their fate

    Russian Opposition Leader Sues Putin for Conflict of Interest

    Alexei Navalny tells VOA in exclusive interview why transfer of $2 billion from country’s wealth fund to company with ties to President Putin’s son-in-law triggered lawsuit

    Clinton, Sanders Fight for African American Votes

    Some African American lawmakers lining up to support Clinton in face of perceived surge by Sanders in race for Democratic nomination in presidential campaign

    Featured Videos

    Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
    As Refugees Perish, Greek Graveyards Filli
    X
    Hamada Elsaram
    February 11, 2016 8:01 PM
    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 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 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 Russia's Catholics, Orthodox Hopeful on Historic Pope-Patriarch Meeting

    Russia's Catholic minority has welcomed an historic first meeting Friday in Cuba between the Pope and the Patriarch of Russia's dominant Orthodox Church. The Orthodox Church split with Rome in 1054 and analysts say politics, both church and state, have been driving the relationship in the centuries since. VOA's Daniel Schearf reports from Moscow.
    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 US Co-ed Selective Service Plan Stirs Controversy

    Young women may soon be required to register with the U.S. Selective Service System, the U.S. government agency charged with implementing a draft in a national emergency. Top Army and Marine Corps commanders told the Senate Armed Services Committee recently that women should register, and a bill has been introduced in Congress requiring eligible women to sign up for the military draft. The issue is stirring some controversy, as VOA’s Bernard Shusman reports from New York.
    Video

    Video Lessons Learned From Ebola Might Help Fight Zika

    Now that the Ebola epidemic has ended in West Africa, Zika has the world's focus. And, as Carol Pearson reports, health experts and governments are applying some of the lessons learned during the Ebola crisis in Africa to fight the Zika virus in Latin America and the Caribbean.
    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 Illinois Voters Have Mixed Emotions on Obama’s Return to Springfield

    On the ninth anniversary of the launch of his quest for national office, President Barack Obama returned to Springfield, Illinois, to speak to the Illinois General Assembly, where he once served as state senator. His visit was met with mixed emotions by those with a front-row seat on his journey to the White House. VOA's Kane Farabaugh reports.
    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.
    Video

    Video Heated Immigration Debate Limits Britain’s Refugee Response

    Compared to many other European states, Britain has agreed to accept a relatively small number of Syrian refugees. Just over a thousand have arrived so far -- and some are being resettled in remote corners of the country. Henry Ridgwell reports on why Britain’s response has lagged behind its neighbors.
    Video

    Video Russia's Car Sales Shrink Overall, But Luxury and Economy Models See Growth

    Car sales in Russia dropped by more than a third in 2015 because of the country's economic woes. But, at the extreme ends of the car market, luxury vehicles and some economy brands are actually experiencing growth. VOA's Daniel Schearf reports from Moscow.