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

Obama: Alaskans Feel Signs of Climate Change

They're seeing bigger storm surges as sea ice melts, more wildfires, erosion of glaciers, shorelines More

Katrina Brought Enduring Changes to New Orleans

The city’s recovery is the result of the people and culture the city is famous for, as well as newcomers and start-up industries More

Magical Photo Slides Show Native Americans in Late 1800s

Walter McClintock spent 20 years photographing the Blackfoot Indians and their vanishing culture at the dawn of the modern age More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Colombians Flee Venezuela as Border Crisis Escalatesi
X
August 27, 2015 2:08 AM
Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Colombians Flee Venezuela as Border Crisis Escalates

Hundreds of Colombians have fled Venezuela since last week, amid an escalating border crisis between the two countries. Last week, Venezuelan President Nicolas Maduro ordered the closure of a key border crossing after smugglers injured three Venezuelan soldiers and a civilian. The president also ordered the deportation of Colombians who are in Venezuela illegally. Zlatica Hoke reports.
Video

Video Is China's Economic Data Accurate?

Some investors say China's wild stock market gyrations have been made worse by worries about the reliability of that nation's economic data. And some critics say the reports can mislead investors by painting an unrealistically-strong picture of the economy. A key China scholar says Beijing is not fudging ((manipulating)) the numbers, but that the economy is evolving quickly from smoke-stack industries to services, and the ways of tracking new economic activity are falling behind the change. V
Video

Video Next to Iran, Climate at Forefront of Obama Agenda

President Barack Obama this week announced new initiatives aimed at making it easier for Americans to access renewable energy sources such as solar and wind. Obama is not slowing down when it comes to pushing through climate change measures, an issue he says is the greatest threat to the country’s national security. VOA correspondent Aru Pande has more from the White House.
Video

Video Shipping Containers Provide Experimental Housing

Housing prices around the San Francisco Bay area are out of reach for many people, so some young entrepreneurs, artists and tech industry workers are creating their own houses using converted shipping containers. But as VOA's Mike O’Sullivan reports from Oakland, the effort requires ingenuity and dealing with restrictive local laws.
Video

Video Arctic Draws International Competition for Oil

A new geopolitical “Great Game” is underway in earth’s northernmost region, the Arctic, where Russia has claimed a large area for resource development and President Barack Obama recently approved Shell Oil Company’s test-drilling project in an area under U.S. control. Greg Flakus reports.
Video

Video Philippine Maritime Police: Chinese Fishermen a Threat to Country’s Security

China and the Philippines both claim maritime rights in the South China Sea.  That includes the right to fish in those waters. Jason Strother reports on how the Philippines is catching Chinese nationals it says are illegal poachers. He has the story from Palawan province.
Video

Video Technique May Eliminate Drill-and-Fill Dental Care

Many people dread visiting dentists because they're afraid of drills. Now, however, a technology developed by a British firm promises to eliminate the need for mechanical cleaning of dental cavities by speeding a natural process of tooth repair. VOA’s George Putic reports.
Video

Video China's Spratly Island Building Said to Light Up the Night 'Like A City'

Southeast Asian countries claim China has illegally seized territory in the Spratly islands. It is especially a concern for a Philippine mayor who says Beijing is occupying parts of his municipality. Jason Strother reports from the capital of Palawan province, Puerto Princesa.
Video

Video Ages-old Ice Reveals Secrets of Climate Change

Ice caps don't just exist at the world's poles. There are also tropical ice caps, and the largest sits atop the Peruvian Andes - but it is melting, quickly, and may be gone within the next 20 years. George Putic reports scientists are now rushing to take samples to get at the valuable information about climate change locked in the ice.
Video

Video French Experiment in Integrating Roma Under Threat

Plans to destroy France’s oldest slum have sparked an outcry on the part of its Roma residents. As Lisa Bryant reports from the Paris suburb of La Courneuve, rights groups argue the community is a fledgling experiment on integrating Roma who are often outcasts in many parts of Europe.
Video

Video Kenyans Turn to Agriculture for Business

Each year Kenyan universities continue to churn out graduates for the job market despite the already existing high rate of unemployment among youth in the country. Some of these young men and women have realized that agriculture can be as rewarding as any other business or job, and they are resorting to agribusiness in large numbers as a way of tackling unemployment. Rael Ombuor reports for VOA.
Video

Video First Women Graduate Elite Army Ranger School

Two women are making history for the U.S. Army by proving they are among the toughest of the tough. VOA's Carla Babb reports from Fort Benning, Georgia as 94 men and those two women rise as graduates of the difficult Ranger school.

VOA Blogs