Loss of food cited as cause of woolly mammoths’ demise

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A major decline in plant diversity resulted in the extinction of the woolly mammoth, woolly rhinoceros and many other large animals following the last Ice Age, according to a new study published in the journal Nature.

Relying on DNA-based research, the Centre for GeoGenetics at the Natural History Museum of Denmark has found that the flowering plants that mammoths and other large creatures depended on for survival disappeared from North American and northern Asia during the last glacial period, eliminating a major food source for the animals.

Prior the that period, the landscapes of the Northern hemisphere were far more diverse and stable than today’s steppes, with megafauna like woolly rhinos and mammoths feeding on grasses and protein-rich flowering plants, or forbs.

But at the height of the last Ice Age – 25,000-15,000 years ago, at a time when the climate was at its coldest and driest – a major loss of plant diversity occurred, the study’s authors wrote.

As a result, the giant animals barely survived.

Once the Ice Age ended about 10,000 years ago the climate warmed again. However, the protein-rich forbs did not recover to their former abundance and were replaced with different kinds of vegetation, including grasses prevalent on today’s plains and steppes.

“This likely proved fatal for species like woolly rhino, mammoth, and horse in Asia and North America,” according to the University of Copenhagen. “Even though it became warmer again after the end of the Ice Age the old landscapes did not return.”

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La Salle expedition wreck being restored

Researchers in Texas are freeze-drying the remains of French ship that, when it sank more than 320 years ago, ultimately altered the course of North American history.

The La Belle was captained by Rene-Robert Cavelier Sieur de La Salle, who had hoped to colonize Texas for France.

When the 54-1/2-foot vessel foundered in 1686 in a storm on Matagorda Bay, about midway between Galveston and Corpus Christi, La Salle’s colony was fated for oblivion.

“When La Belle sank, that doomed La Salle’s colony and opened up the door for Spain to come in and occupy Texas,” said Jim Bruseth, who led the Texas Historical Commission effort to recover the remains.

By placing the ship in a constant environment of up to 60 degrees below zero, more than 300 years of moisture will be safely removed from hundreds of European oak and pine timbers and planks, according to The Telegraph.

The operation, taking place at the old Bryan Air Force base several miles northwest of College Station, Texas, is the first such undertaking of its size.

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Confederate cannons to be sought in Pee Dee

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A team of underwater archaeologists from the University of South Carolina will begin work to locate and raise three Confederate cannons – each weighing upwards of 5 tons – from the silty sediment at the bottom of Mars Bluff on the Pee Dee River later this year.

Researchers from the SC Institute for Archaeology and Anthropology will use remote sensing technology, including a magnetometer that identifies the presence of iron, to survey the Confederate Mars Bluff Navy Yard on the Pee Dee River and locate cannons, according to information from the school.

The Mars Bluff Naval Yard was one of seven Confederate naval yards that were located inland so gunboats and support vessels for the war could be built and protected from Union forces. Mars Bluff was chosen for its inland location, proximity to the railroad, water communication with Charleston via Georgetown and the abundance of ash, oak and pine lumber.

The cannons to be located and recovered are from the 170-foot gunboat C.S.S. Pee Dee, which was constructed at Mars Bluff and launched in January 1865. The Pee Dee’s career was cut short when Gen. William T. Sherman’s Union troops advanced northward, leading to the destruction of the naval yard and the scuttling of the Pee Dee on March 15, 1865.

Historic records are scanty, but indicate that the Pee Dee had two Confederate brooks rifled cannons and one captured Union Dahlgren, smooth-bore, nine-inch shell cannon on board at the time of the ship’s sinking.

Little else is known about the Pee Dee, other than she was a twin-screw gunboat. One engine was ordered from the Naval Iron Works in Richmond and the other is believed to have run the blockade from Great Britain.

The survey is set to begin April 30, with location of the cannons and excavation of the Naval Yard taking place in late May to mid-June. Once located and verified, the cannons will be raised as early as this fall.

The project is funded in part by a $200,000 grant from the Drs. Bruce and Lee Foundation in Florence.

Artifacts from the Mars Bluff Naval Yard and the CSS Pee Dee can be found at the War Between The States Museum in Florence.