Jul 21, 2019 | Updated: 08:54 AM EDT

The Last Days Of The Wooly Mammoth: Genetic Meltdown Influenced Their Demise

Mar 07, 2017 11:34 AM EST

Tyrannosaurus Rex Skeleton To Be Auctioned Off In Las Vegas
(Photo : Ethan Miller/Getty Images) LAS VEGAS - SEPTEMBER 30: A woolly mammoth skeleton with 90 percent of its original bones is displayed at the Venetian Resort Hotel Casino September 30, 2009 in Las Vegas, Nevada. Auctioneers Bonhams & Butterfields hope the 11-foot tall fossil will fetch about USD 150,000-200,000 when it is auctioned off on October 3 at the Venetian as part of their Natural History auction. The centerpiece of the lot of 50 fossils being auctioned is a 66-million-year-old Tyrannosaurus rex skeleton dubbed 'Samson.' The 40-foot-long female dinosaur fossil, excavated in South Dakota in 1992, contains about 170 bones and is said to be the third most complete T. rex skeleton ever unearthed. Bonhams & Butterfields is hoping Samson will fetch more than USD 6 million at the auction.

It has been found that wooly mammoths had suffered a genetic meltdown during their final days on Earth. At their prime, wooly mammoths had dominated most of Siberia, Alaska and several parts of North America. But as the climate turned warmer some 10,000 years ago, the wooly mammoths faced an extreme challenge which, unfortunately, they were unable to overcome.

First of all, the change in climate had turned the grasslands where the mammoths had grazed into forests and to add more conflict to their already diminishing situation, humans hunted them relentlessly as hunting one mammoth provided quite the bountiful feast. Eventually, the wooly mammoths then vanished from the mainland. However, a small group of them would hideout in an island in the Arctic, Wrangel Island, and survive some 6000 years more before truly vanishing from the face of the earth.

A new study reveals that the last wooly mammoths suffered from a 'genetic meltdown' which contributed to their population's demise. By comparing DNA from a 45,000-year-old wooly mammoth tissue to DNA from a 4,300-year-old wooly mammoth tooth from Wrangel Island, scientists have discovered that the latter contained an excess of bad mutations, BBC reports. According to Dr. Rebekah Rogers of the University of California, Berkeley, when there is only a small population of a species on an extended period of time the species can go into a genomic meltdown.

In the wooly mammoths of Wrangel Island's case, natural selection became inefficient due to the small population and the wooly mammoths weren't able to weed out the bad genes from the good ones. In a different report published in the New York Times, it is revealed that the Wrangel Island wooly mammoths have accumulated many mutations in their genes resulting even in the loss of the olfactory genes as well as other components that affect mammoth behavior and disrupting their social status and mate choice.

One damaged gene found in the DNA sample is FOXQ1 which turned their hair shiny and less stiff, giving a more satin-like appearance. Mammoths usually have thick and rough hair which provides them effective insulation. But with the damage in the FOXQ1 gene, their insulation has ultimately been jeopardized as well as their survival.

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