Scientists solve the 320-year-old mystery of how the
Experts were baffled by how the now extinct animal crossed the sea
Mystery was first recorded in 1690 - and raised again by Charles Darwin
Researchers analysed DNA from famously tame animal found by Darwin
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It is a mystery that has puzzled biologists - including Charles Darwin - for 320 years.
Biologists had been unable to work out how the Falklands
wolf came to be the only land-based mammal on the isolated islands, which are
460km from the nearest land,
Previous theories have suggested the wolf somehow rafted on ice or vegetation, crossed via a now-submerged land bridge or was even semi-domesticated and transported by early South American humans.
Illustration of 'Dusicyon australis', the
THE
The Falkland Islands wolf (Dusicyon australis), is also
known as the warrah and occasionally as the
It was the only native land mammal of the
The first recorded sighting was by Captain John Strong in
1690. He took one, but during the voyage back to
When Charles Darwin visited the islands in 1833 he found the
species present on both West and
Islanders hunted it for its fur, and were also concerned it would attack sheep.
Now,
Researchers from the University’s Australian Centre for
Ancient DNA (ACAD) extracted tiny pieces of tissue from the skull of a specimen
collected personally by
The 320-year-old mystery was first recorded by early British explorers in 1690 and raised again by Charles Darwin following his encounter with the famously tame species on his Beagle voyage in 1834.
The findings were published in Nature Communications today and concluded that, unlike earlier theories, the Falkland Islands wolf (Dusicyon australis) only became isolated about 16,000 years ago around the peak of the last glacial period.
'The eureka moment was finding evidence of submarine
terraces off the coast of
'They recorded the dramatically lowered sea levels during the Last Glacial Maximum (around 25-18,000 years ago).'
'At that time, there was a shallow and narrow (around 20km) strait between the islands and the mainland, allowing the Falkland Islands wolf to cross when the sea was frozen over, probably while pursuing marine prey like seals or penguins.
'Other small mammals like rats weren’t able to cross the ice.'
The team also used samples from a previously unknown
specimen, which was recently re-discovered as a stuffed exhibit in the attic of
The 'submarine terraces' that enabled the Falklands wolf to
cross from
The yellow dots show the areas in
'Previous studies used ancient DNA from museum specimens to suggest that the Falkland Islands wolf diverged genetically from its closest living relative, the South American maned wolf (Chrysocyon brachyurus) around seven million years ago,' said Associate Professor Jeremy Austin, Deputy Director of ACAD and co-lead author with Dr Julien Soubrier.
'As a result, they estimated that the wolf colonised the islands about 330,000 years ago by unknown means.
'Critically, however, these early studies hadn’t included an extinct relative from the mainland, the fox-like Dusicyon avus.
'We extracted ancient DNA from six specimens of D. avus
collected across
ACAD’s analyses showed that D. avus was the closest relative
of the
The Falkland Islands wolf (Dusicyon australis), also known
as the warrah and occasionally as the
It was the only native land mammal of the
The Falklands wolf had baffled scientists, as they could not
work out how it crossed from
The first recorded sighting was by Capt. John Strong in 1690.He took one, but during the voyage back to Europe it became frightened by the firing of the ship's cannon and jumped overboard.
When Charles Darwin visited the islands in 1833 he found the
species present on both West and
Islanders hunted it for its fur, and were also concerned it would attack sheep.
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