http://www.guardian.co.uk/science/2013/mar/05/fossilised-giant-camel-bone-found

Fossilised giant camel bone found in High Arctic
Ancient beast stood almost three metres tall at the hump, about a third higher 
than its modern descendant

  a.. 
  a.. Ian Sample, science correspondent 
  b.. guardian.co.uk, Tuesday 5 March 2013 16.27 GMT 
  c.. 
 
The High Arctic camel on Ellesmere Island during the Pliocene warm period, 
about 3.5m years ago. Illustration: Julius T Csotonyi
Fossil hunters have unearthed fragments of leg bone belonging to a giant camel 
that lived in the forests of the High Arctic more than three million years ago.

The ancient beast stood almost three metres tall at the hump, about a third 
higher than its modern descendant, the single-humped dromedary, or Arabian 
camel.

Scientists who found the remains said the extinct mammal may have already had 
the wide, flat feet and fatty hump associated with adaptation to life in the 
desert, because they could have helped the animal endure its harsh, 
snow-covered habitat.

Remnants of the oversized ungulate, 30 pieces in all, were recovered from a 
steep, sandy slope at Fyles Leaf Bed on Ellesmere island, the most northern and 
mountainous of the Canadian Arctic archipelago.

The sediments around the fossils date to at least 3.4m years old, when the 
region was much warmer than today and dominated by larch forests. Temperatures 
hovered a few degrees below zero, and winters plunged the region into six 
months of darkness.

Fossils from previous expeditions have shown that the camel's ancestors 
originated in North America 45m years ago, and crossed the Bering Strait into 
China and Eurasia more than 7m years ago. In 1913, the first giant camel 
remains were uncovered in Yukon, about 1,200km south of the Fyles Leaf Bed site.

"This is the first evidence of camels in the High Arctic," said Mike Buckley, a 
researcher at Manchester University who studied the remains.

The frigid conditions on Ellesmere island preserved connective tissue called 
collagen in the specimens. When Buckely compared the chemical makeup of the 
collagen with tissue from the Yukon camels, he found they were closely related, 
and possibly the same species. They also matched modern dromedaries, but not 
the twin-humped Bactrian camel. The study appears in the journal, Nature 
Communications.

"This ancestor of modern camels may already have had some of the adaptations 
that helped it survive in harsh climates – the hump for fat storage for 
instance. The large flat feet were ideal for soft ground, so it didn't sink 
through sand or snow. The large eyes perhaps helped with poor visibility in the 
long, dark winters," said Buckley.

No other mammal remains have been unearthed at Fyles Leaf bed, but at a nearby 
site, expeditions uncovered fossilised remnants from a beaver, a three-toed 
horse and a badger, that lived at the same time.

"We now have a new fossil record to better understand camel evolution," said 
Natalia Rybczynski, at the Canadian Museum of Nature in Ontario. "Perhaps some 
specialisations seen in modern camels, such as their wide flat feet, large eyes 
and humps for fat may be adaptations derived from living in a polar 
environment."


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