Subscribe free to our newsletters via your
. 24/7 Space News .




ICE WORLD
New study points finger at climate in mammoth's demise
by Staff Writers
Paris (AFP) Sept 10, 2013


A wide-ranging probe into woolly mammoths has added to evidence that the towering tusker was wiped out by climate change, scientists said on Wednesday.

British and Swedish researchers sequenced DNA from 88 samples of mammoth bone, tooth and tusk, looking for a signature in the genetic code that is handed down on the maternal line.

They used this telltale to build a family tree of mammoths spanning 200,000 years, across northern Eurasia and North America.

They found two periods of big population shakeup, both of them occurring in "interglacials," or periods between ice ages.

A warm period 120,000 years ago caused populations to decline and become fragmented, leading to the emergence of a distinct type of mammoth that lived in western Europe.

The cold then returned, for a period lasting around 100,000 years called the Late Pleistocene -- the last ice age until now.

Superbly adapted to the cold, arid steppe and tundra, mammoths were the kings of the north.

They ruled from western Europe to the northern part of North America, which could be reached from Eurasia by an ice bridge across the Bering Strait.

Then as the temperatures gradually rose once more, the populations shifted again and the mammoths were again confined to small pockets of favourable habitat.

What happened next is the final chapter in the great mammoth mystery.

Other researchers have similarly concluded that climate change drove the mammoth to the brink but say it was hunting by humans that delivered the final blow.

But this argument has a flaw.

Humans could hardly be to blame if mammoths were able -- as in previous interglacials -- to hole up in some chilly redoubt that was too remote for habitation or hunting.

"Spells of warm climate made the mammoth more susceptible to extinction," said Love Dalen at the Swedish Museum of Natural History.

But to understand why the entire species became extinct, further investigations are needed in the final places where mammoths survived, said Dalen.

Two good candidate locations are St. Paul, an island off Alaska, and Wrangel, an island in the Siberian Arctic, said co-researcher Ian Barnes at London's Royal Holloway University.

Wrangel Island, in the Siberian Arctic, and the island of St. Paul, off Alaska, are believed to have been the mammoths' last refuge.

Populations there may have survived as recently as 6,000 years ago, some 5,000 years later than counterparts on the mainland.

The study appears in Proceedings of the Royal Society B, published by Britain's de-facto Academy of Sciences.

.


Related Links
Beyond the Ice Age






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle








ICE WORLD
Penn Study Finds Earlier Peak for Spain's Glaciers
Philadelphia PA (SPX) Sep 10, 2013
The last glacial maximum was a time when Earth's far northern and far southern latitudes were largely covered in ice sheets and sea levels were low. Over much of the planet, glaciers were at their greatest extent roughly 20,000 years ago. But according to a study headed by University of Pennsylvania geologist Jane Willenbring, that wasn't true in at least one part of southern Europe. Due t ... read more


ICE WORLD
Scientists say water on moon may have originated on Earth

Moon landing mission to use "secret weapons"

NASA launches spacecraft to study Moon atmosphere

NASA-Funded Scientists Detect Water on Moon's Surface that Hints at Water Below

ICE WORLD
Terramechanics research aims to keep Mars rovers rolling

New technology could make for smarter planet rovers

India prepares to launch country's maiden mission to Mars

SwRI study suggests debris flows on frozen arctic sand dunes are similar to dark dune spot-seepage flows on Mars

ICE WORLD
SpaceShipTwo commercial space liner breaks sound barrier in test

Andreas Mogensen set for Soyuz mission to ISS in 2015

NASA awards nearly $1.5B in support contracts

NSBRI and NASA Reduce Space Radiation Risks by Soliciting for Center of Space Radiation Research

ICE WORLD
China civilian technology satellites put into use

China to launch lunar lander by end of year: media

China launches three experimental satellites

Medical quarantine over for Shenzhou-10 astronauts

ICE WORLD
Three astronauts back on Earth from ISS: mission control

ISS Crew Completes Spacewalk Preps

Russian cosmonaut set for space station mission resigns

Russian cosmonauts to start searching for bacterium corroding ISS body

ICE WORLD
Japan sets new date for satellite rocket launch

Arianespace delivers! EUTELSAT 25B/Es'hail 1 and GSAT-7 are orbited by Ariane 5

Arianespace to "reach for the stars" with its Soyuz launch of Europe's Gaia space surveyor spacecraft

Ariane 5 build-up is completed for Arianespace upcoming flight with EUTELSAT

ICE WORLD
Coldest Brown Dwarfs Blur Lines between Stars and Planets

NASA-funded Program Helps Amateur Astronomers Detect Alien Worlds

Observations strongly suggest distant super-Earth has water atmosphere

Waking up to a new year

ICE WORLD
Chinese-built Bolivian satellite tested in space simulator

Indiana Jones meets George Jetson

New computational approaches speed up the exploration of the universe

Advancing graphene for post-silicon computer logic




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement