Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. Earth Science News .




ICE WORLD
New clues to decline and extinction of woolly mammoths
by Staff Writers
Amsterdam, Netherlands (SPX) Mar 27, 2014


The arrow indicates a large articulation facet of a cervical rib on a fossil cervical vertebra of a woolly mammoth of the Natural History Museum Rotterdam. Image courtesy Joris van Alphen.

Researchers recently noticed that the remains of woolly mammoths from the North Sea often possess a 'cervical' (neck) rib-in fact, 10 times more frequently than in modern elephants (33.3% versus 3.3%).

In modern animals, these cervical ribs are often associated with inbreeding and adverse environmental conditions during pregnancy. If the same factors were behind the anomalies in mammoths, this reproductive stress could have further pushed declining mammoth populations towards ultimate extinction.

Mammals, even the long-necked giraffes and the short-necked dolphins, almost always have seven neck vertebrae (exceptions being sloths, manatees and dugongs), and these vertebrae do not normally possess a rib. Therefore, the presence of a 'cervical rib' (a rib attached to a cervical vertebra) is an unusual event, and is cause for further investigation.

A cervical rib itself is relatively harmless, but its development often follows genetic or environmental disturbances during early embryonic development. As a result, cervical ribs in most mammals are strongly associated with stillbirths and multiple congenital abnormalities that negatively impact the lifespan of an individual.

Researchers from the Rotterdam Museum of Natural History and the Naturalis Biodiversity Center in Leiden examined mammoth and modern elephant neck vertebrae from several European museum collections. "It had aroused our curiosity to find two cervical vertebrae, with large articulation facets for ribs, in the mammoth samples recently dredged from the North Sea.

"We knew these were just about the last mammoths living there, so we suspected something was happening. Our work now shows that there was indeed a problem in this population", said Jelle Reumer, one of the authors on the study published today in the open access journal PeerJ.

The incidence of abnormal cervical vertebrae in mammoths is much higher than in the modern sample, strongly suggesting a vulnerable condition in the species. Potential factors could include inbreeding (in what is assumed to have been an already small population) as well as harsh conditions such as disease, famine, or cold, all of which can lead to disturbances of embryonic and fetal development.

Given the considerable birth defects that are associated with this condition, it is very possible that developmental abnormalities contributed towards the eventual extinction of these late Pleistocene mammoths.

The peer-reviewed study, entitled "Extraordinary incidence of cervical ribs indicates vulnerable condition in Late Pleistocene mammoths" was authored by Jelle Reumer of the Rotterdam Museum of Natural History and Clara ten Broek and Frietson Galis of Naturalis Biodiversity Center (Leiden). Reumer et al. (2014), Extraordinary incidence of cervical ribs indicates vulnerable condition in Late Pleistocene mammoths. PeerJ 2:e318; DOI 10.7717/peerj.318

.


Related Links
PeerJ
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




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





ICE WORLD
Glacial advances in Nyainqentanglha maybe linked to North Atlantic cooling
Beijing, China (SPX) Mar 24, 2014
Chronologies of glacial advances during the last glacial period are not contemporaneous throughout the Tibetan Plateau. Professor YI Chaolu and his research group from the Institute of Tibetan Plateau Research, Chinese Academy of Sciences, dated glacial boulders on moraines from the last glacial period in the Nyainqentanglha Mountains, Tibet. They suggested that glacial advances that occur ... read more


ICE WORLD
Eight killed, 108 unaccounted for in huge US landslide

Malaysia in uncharted territory on MH370 crash probe

MH370 relatives stage Beijing march against Malaysia

MH370 search back on as weather improves

ICE WORLD
China's rare earth trade limits break global rules: WTO

MIT engineers design 'living materials'

Unavoidable disorder used to build nanolaser

Cisco pushes into 'cloud' with $1 bn investment

ICE WORLD
Lots of carbon dioxide equivalents from aquatic environments

Deep Ocean Current May Slow Due to Climate Change

Global warming may increase methane emissions from freshwater ecosystems

High-tech materials purify water with sunlight

ICE WORLD
Ancient Indonesian climate shift linked to glacial cycle

Glacial advances in Nyainqentanglha maybe linked to North Atlantic cooling

Permafrost Thaw Exacerbates Climate Change

Braving perilous Drake Passage to Brazil's Antarctic base

ICE WORLD
Flood of dead pigs in China reservoir: report

Stanford professor maps by-catch as unintended consequence of global fisheries

Research reveals true value of cover crops to farmers, environment

Small, compact hyperspectral sensor ideal for farm field

ICE WORLD
Text messages aim to save lives in flood-prone Africa

Off-rift volcanoes explained

Ground-improvement methods might protect against earthquakes

Strong quake strikes off Chile

ICE WORLD
Underfunded S.Africa military in 'critical decline': review

France calls for more European troops for C.Africa mission

Chinese nationals held in Nigeria for illegal fishing

Peacekeepers seize large weapons cache in C. Africa

ICE WORLD
Eyes are windows to the soul -- and evolution

New stratigraphic research makes Little Foot the oldest complete Australopithecus

Stirring the simmering 'designer baby' pot

Empathy chimpanzees offer is key to understanding human engagement




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news 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 All images and articles appearing on Space Media Network have been edited or digitally altered in some way. Any requests to remove copyright material will be acted upon in a timely and appropriate manner. Any attempt to extort money from Space Media Network will be ignored and reported to Australian Law Enforcement Agencies as a potential case of financial fraud involving the use of a telephonic carriage device or postal service.