Thursday, March 30, 2017
Contact us    |    Advertise    |   Help   RSS icon Twitter icon Facebook icon
    Home  ·  News  ·  Forum  ·  Stories  ·  Image Gallery  ·  Columns  ·  Encyclopedia  ·  Videos
Find: in

DNA offers clues to woolly mammoth's demise


Posted on Saturday, 4 March, 2017 | Comment icon 13 comments

The mammoth held on until around 4,000 years ago. Image Credit: Charles Robert Knight
An analysis of mammoth DNA has revealed that the species had become wracked with genetic disease.
Study leader Dr Rebekah Rogers from the University of California, Berkeley maintains that just before it went extinct, the woolly mammoth had gone into "genomic meltdown".

The DNA sample in question had come from a mammoth which lived around 4,000 years ago - a time when the species had been all but wiped out save for a few isolated island populations.

To confirm the findings, the researchers also analyzed the DNA of a mammoth from 45,000 years ago which did not show the same signs of genetic disease as its more recent counterpart.

"You had this last refuge of mammoths after everything has gone extinct on the mainland," said Dr Rogers. "The mathematical theories that have been developed said that they should accumulate bad mutations because natural selection should become very inefficient."

The discovery is worrying as similar issues could also plague some of today's endangered species.

"When you have these small populations for an extended period of time they can go into genomic meltdown, just like what we saw in the mammoth," said Dr Rogers.

"So if you can prevent these organisms ever being threatened or endangered then that will do a lot more to help prevent this type of genomic meltdown compared to if you have a small population and then bring it back up to larger numbers."

Source: BBC News | Comments (13)

Tags: Mammoth, DNA


 
Recent comments on this story
Comment icon #4 Posted by godnodog on 5 March, 2017, 12:40
Ice ages are cyclic. http://earthguide.ucsd.edu/virtualmuseum/climatechange2/01_1.shtml
Comment icon #5 Posted by EBE Hybrid on 5 March, 2017, 21:40
It sounds as if the last herd of mammoth had a lack of genetic variety, genetic defects becoming more common as they were past from one generation to the next. Norfolf!!!!
Comment icon #6 Posted by Carnoferox on 5 March, 2017, 21:44
The Wrangel Island population of mammoths had such a high number of genetic defects because they were inbreeding. Genetic bottlenecks happen when animals become stranded on smallislands with limited resources. However, these geneticdefects did not cause the extinction of the species as a whole.
Comment icon #7 Posted by Farmer77 on 5 March, 2017, 21:55
Could geographic isolation due to human predation create conditions for sustained interbreeding and genetic degradation?
Comment icon #8 Posted by oldrover on 5 March, 2017, 22:38
This is one of the key aspects to a major theory about the megafauna extinction in general.
Comment icon #9 Posted by Carnoferox on 5 March, 2017, 22:51
Definitely. That is what happened to the Wrangel Island woolly mammoths. However, it is not known for sure if the geographic isolation was caused by human hunting. A more likely explanation is the gradualdisappearance of the mammoth steppe (the natural habitat of the woolly mammoth and numerous other species)and its replacement with boreal forests.
Comment icon #10 Posted by oldrover on 5 March, 2017, 23:48
It's also one of the factors which played a part in the extinction of the thylacine, and the decline in devil numbers de to DFTD. Not necessarily in the case of the thylacine initially through human agency, and not in the case of the devil. Both instances are the result of geographic isolation. However with the tiger human hunting and land alteration probably exacerbated the effect. The same has I believe been postulated for hunting patterns in N America during the late Pliestocene early Holocene. Extinction has lots of little helpers.
Comment icon #11 Posted by AnchorSteam on 6 March, 2017, 18:59
Wrangle wasn't always an island, the Mammoths didn't swim there. Jean Auel said that it was habitat lose that did them in; their environment was the edge of the Glaciers, almost literally. Wrangle may have been the last place in the world they felt comfortable.
Comment icon #12 Posted by Carnoferox on 6 March, 2017, 19:24
Woolly mammoths reached Wrangel Island while it was still part of the Bering Land Bridge, then became trapped as sea levels rose again. Habitat loss was a major contributing factor to the extinction of the woolly mammoth. Woolly mammoth habitat wasn't right at the edge of glaciers though, but rather on the wide open steppe. Auel is just an author (not a paleontologist), so I wouldn't use her as a reliable source.
Comment icon #13 Posted by AnchorSteam on 6 March, 2017, 21:01
Yeah, but I liked her books.


Please Login or Register to post a comment.


  On the forums
Forum posts:
Forum topics:
Members:

5873581
252511
166423

 
Man eats pancakes in the middle of the road
3-29-2017
A prankster was charged this week after being filmed tucking in to pancakes at a busy intersection.
Statue of King Tut's grandmother unearthed
3-29-2017
A rare alabaster carving of Queen Tiye has been discovered along the west bank of the River Nile.
Firm plans to build upside-down skyscraper
3-29-2017
The bizarre plan would see the world's tallest building being hung upside-down from an orbiting asteroid.
Woman blames car crash on Bigfoot sighting
3-28-2017
An unidentified motorist ended up hitting a deer in her car after being distracted by a 'hairy beast'.
Featured book
 
By Guy Lyon Playfair
A look at the story of Peggy Hodgson and her four children who, between 1977 and 1979, were at the center of one of the most terrifying poltergeist cases ever documented.
Featured Videos
Gallery icon 
Bird of paradise courtship spectacle
Posted 3-29-2017 | 0 comments
A look at the extreme lengths birds of paradise go to in order to attract a mate.
 
Mythical monsters
Posted 3-28-2017 | 1 comment
Jeremy Wade investigates the stories behind some of the world's best known monster myths.
 
6ft rockets in slow motion
Posted 3-27-2017 | 0 comments
The Slo Mo Guys use their high-speed camera to record some rocket launches.
 
Most watched animal on YouTube
Posted 3-26-2017 | 2 comments
Maru the cat has accumulated more views than any other animal on the video sharing site.
 
ALMA's 100-ton antennas
Posted 3-25-2017 | 0 comments
A special vehicle is used to carry ALMA's ultra-heavy antennas in to place in the desert.
 
 View: More videos
Stories & Experiences
My nightly occurrences
2-28-2017 | Manchester, UK
 
Saved by a stranger
2-7-2017 | Green River Wyoming
 
Spooky sense
2-4-2017 | India
 
Ghost car
2-4-2017 | Chicago, IL, USA
 
Mysterious powder
2-4-2017 | USA, North Carolina
 
Puerto Rico UFO sighting
2-4-2017 | Sabana Grande, Puerto Rico
 
Phantom vehicle
1-6-2017 | Ramer, United States
 
True ghost stories
1-6-2017 | Southern California
 
Floating tiles
1-6-2017 | Chewelah, Washington
 
A haunting in Northern California
12-28-2016 | Northern California
 

         More stories | Send us your story
 
Top   |  Home   |   Forum   |   News   |   Image Gallery   |  Columns   |   Encyclopedia   |   Videos   |   Polls
UM-X 10.7 Unexplained-Mysteries.com 2001-2017
Privacy Policy and Disclaimer   |   Cookies   |   Advertise   |   Contact   |   Help/FAQ