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Woolly mammoths survived on remote Arctic island for 7,000 YEARS longer than their continental cousins – before 'humans arrived and wiped them out'

The last mammoths, who lived on Wrangel Island, Arctic ocean, died suddenlyScientists uncovered a number of factors that may have sealed mammoths' fateExtreme weather, starvation and human contribution could have played a part 

The last of the woolly mammoths appear to have lived on an island in the Arctic and survived for 7,000 years longer than those on the mainland.

Researchers suggested the prehistoric beasts were separated as the land masses moved around, and extinction moved more slowly on the island.

They lived on Wrangel Island, which is to the north of where Russia and Alaska come close to meeting.

Groups of the mammals on the continent contain evidence of DNA mutations as they approached extinction, but these are less apparent in the Wrangel Island fossils.

Scientists have found they were wiped out suddenly about 4,000 years ago, likely by a combination of humans arriving, extremely cold weather, and deteriorating drinking water quality. 

Woolly mammoths survived on remote Arctic island for 7,000 YEARS longer than their continental cousins – before 'humans arrived and wiped them out'

An illustration of a family of Woolly Mammoths grazing on what is left of the grasses as winter approaches in this ice age scene (stock image)

Around 4,000 years ago the last surviving mammoths who lived on Wrangel Island in the Arctic Ocean died out suddenly

Researchers at the University of Helsinki and Tübingen and the Russian Academy of Sciences said a combination of factors likely led to the later mammoths' demise.

A combination of factors is believed to have sealed the ancient giants' fate including their location on the isolated island, exposure to extreme weather events and even the introduction of prehistoric humans to the island. 

Mammoths were widespread across most of the Northern hemisphere from Spain to Alaska during the last ice age, around 100,000 to 15,000 years ago. 

But global warming that began 15,000 years ago saw the mammoths reign dwindle as their icy habitats of Alaska and northern Siberia shrank.  

The study, published in the latest edition of Quaternary Science Reviews, detailed how a small population of mammoths, cut off from mainland Siberia and Alaska, outlived the rest of the species by 7,000 years. 

It was the remnants of this long surviving population of Wrangel Island that researchers used to compare with the bones and teeth of mammoths from Northern Siberia, Alaska, the Yukon.

Scientists from Finland, Germany and Russia studied isotope compositions of carbon, nitrogen, sulfur and strontium in the mammoth bones and teeth ranging from 40,000 to 4,000 years in age.

HOW MAMMOTHS BRAVED THE COLD 

Genetic research on woolly mammoths has helped to reveal how the ice age giants adapted to survive in the cold expanses of northern Asia and Europe.

Scientists compared the genomes of two woolly mammoths with those of Asian elephants - their closest living relatives - in an attempt to understand the differences between them.

The research found that woolly mammoths and Asian elephants have nearly 1.4 million DNA letters difference between their genomes.

These difference alter more than 1,600 genes, bringing about changes in skin and hair development, fat storage, metabolism and temperature sensation.

One mammoth gene, known as TRPV3, was involved in sensitivity to the cold.

It is thought these adaptations allowed the mammoth to survive in the freezing temperatures during the last ice age, but it is possible they left them ill equipped to cope as the climate warmed.

They discovered that unlike the isotopes found in woolly mammoths from the Ukrainian-Russian plains, who went locally extinct 15,000 years ago,  and the mammoths of St. Paul Island in Alaska, who died out 5,600 years ago, the composition of Wrangel Island mammoths' collagen carbon and nitrogen isotopes did not change with the warming climate.

This suggests that they were not subject to a long-term disturbance in their diet and environment - a fact that has previously left scientists puzzled as to why the mammoths went extinct in what appear to have been favourable conditions.

A change in the DNA of Wrangel Island mammoths was also observed by another study which found mutations in the way the animals metabolised fat.

While Siberian mammoths had to rely on reserves of fat, Wrangel mammoths did not as they did not endure such harsh conditions as their predecessors. 

The two populations showed differences in their carbonate carbon isotope values indicating a change in the fats and carbohydrates in the later population's diet. 

Dr Laura Arppe from the Finnish Museum of Natural History Luomus, University of Helsinki, who led the team of researchers said: 'We think this reflects the tendency of Siberian mammoths to rely on their reserves of fat to survive through the extremely harsh ice age winters, while Wrangel mammoths, living in milder conditions, simply didn't need to.' 

Mammoth tooth on the riverbank on Wrangel Island – scientists used these fossils to determine that mammoths there had survived longer than mainland individuals

Drinking water for the Wrangel Island mammoths may have been affected by the break down of bedrock as higher levels of sulfur and strontium were found in the bones of later members of the population.

With no obvious conclusion as to why the mammals went extinct so quickly researchers can only theorise the short-term events that led to their demise. 

Extreme snow and ice leading to a lack of food and starvation is a likely scenario, say researchers.

Winter sunrise on Wrangell island, Alaska (stock image)

Professor Hervé Bocherens from the Senckenberg Center for Human Evolution who co-wrote the study said: 'It's easy to imagine that the population, perhaps already weakened by genetic deterioration and drinking water quality issues could have succumbed after something like an extreme weather event.' 

However scientists say they have believe human contribution may have played a part. 

Human bones dating just a few hundred years were found on on Wrangle island after the extinction of mammoths, meaning it is possible the spread of humans meant a decline in mammoth numbers leading to extinction. 

Isolated populations of large mammals are found to be particularly vulnerable to human behaviour and environmental factors by the study. 

COULD WE RESURRECT MAMMOTHS?

Male woolly mammoths were around 12 feet (3.5m) tall, while the females were slightly smaller.

They had curved tusks up to 16 feet (5m) long and their underbellies boasted a coat of shaggy hair up to 3 feet (1m) long.

Tiny ears and short tails prevented vital body heat being lost.

Their trunks had 'two fingers' at the end to help them pluck grass, twigs and other vegetation.

They get their name from the Russian 'mammut', or earth mole, as it was believed the animals lived underground and died on contact with light – explaining why they were always found dead and half-buried.

Their bones were once believed to have belonged to extinct races of giants.

Woolly mammoths and modern-day elephants are closely related, sharing 99.4 per cent of their genes.

The two species took separate evolutionary paths six million years ago, at about the same time humans and chimpanzees went their own way.

Woolly mammoths co-existed with early humans, who hunted them for food and used their bones and tusks for making weapons and art. 

The most widely used technique, known as CRISPR/Cas9, allows scientists to create a hybrid animal from the preserved fossils of woolly mammoths and merging it with cells from a living elephant. The two species share 99.4 per cent of their DNA

'De-extincting' the mammoth has become a realistic prospect because of revolutionary gene editing techniques that allow the precise selection and insertion of DNA from specimens frozen over millennia in Siberian ice. 

The most widely used technique, known as CRISPR/Cas9, has transformed genetic engineering since it was first demonstrated in 2012.

The system allows the 'cut and paste' manipulation of strands of DNA with a precision not seen before.

Using this technique, scientists could cut and paste preserved mammoth DNA into Asian elephants to create and elephant-mammoth hybrid. 

Mammoths roamed the icy tundra of Europe and North America for 140,000 years, disappearing at the end of the Pleistocene period, 10,000 years ago.

They are one of the best understood prehistoric animals known to science because their remains are often not fossilised but frozen and preserved.

Topic: #ice #mammoth
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HOT COMMENTS

Chandramani

atleast let's save what is still available

2 Months ago

2
Gandhara

hope some day the scientists will be able to bring them back, hope it happens in my lifetime

2 Months ago

1
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