Featured Research

from universities, journals, and other organizations

Seafloor Creatures Destroyed By Ice Action During Ice Ages

Date:
October 19, 2005
Source:
British Antarctic Survey
Summary:
New research by marine scientists at National Oceanography Centre, Southampton (NOC) and the British Antarctic Survey (BAS) will mean that text books will have to be rewritten. They reveal that ice ages were a time of mass destruction as whole communities of animals were wiped out by ice sheets scouring the sea floor.

Glacier flowing into Marguerite Bay, Antarctic Peninsula.
Credit: Photo grapher: Chris Gilbert

The ice ages made massive changes to the Earth'slandscape. But what was happening below the icein the oceans?

Related Articles


Research by marine scientists reveals that it wasa time of mass destruction as whole communitiesof animals were wiped out by ice sheets scouringthe sea floor.

In the past it has been thought that theseecosystems somehow dodged extinction byrecolonising from nearby habitats that escapedobliteration. But researchers at the NationalOceanography Centre, Southampton (NOC) and theBritish Antarctic Survey (BAS) reveal a bleakerscenario.

Dr Sven Thatje, an ecologist at NOC has beenworking with geoscientists, Dr Claus-DieterHillenbrand and Dr Rob Larter at BAS examiningone of the harshest environments on Earth - theAntarctic seafloor.

Writing in the October issue of Trends in Ecology& Evolution the scientists provide new evidencethat suggests that seafloor organisms were eithererased by the advance of ice sheets across theAntarctic continental shelf or starved to deathas links in the food chain were broken by thepermanent ice cover. There would have been norefuge for shallower living animals further downthe continental slope, as huge sediment slideswould have buried them. Typically theseecosystems would have been made up of sponges,urchins, sea fan corals, and starfish.

Dr Thatje said: 'We show that during ice agesseafloor organisms emigrated to the deep sea -below the effects of the sediment slides and ice.From there, organisms may have invaded openmarine shelters of the Antarctic shelf, whichwere not affected by the advance of ice masses.Or these animals may have recolonised theAntarctic shelf from the deep-sea during the warmperiod following each ice age.

'Either way it is an impressive feat against theodds as the extreme cold means that these animalsrespond much more slowly to the destruction oftheir habitat than elsewhere in the oceans. Theyhave lower metabolic rates that lower theirgrowth and reproductive rates. Elsewhere in theoceans, a brisingid starfish would reproduceannually and live for ten years. In the Antarcticthese starfish can reach 100-years-old butreproduce only once every ten years. This meansthat full community recuperation takes up tohundreds of years.'

Dr Claus-Dieter Hillenbrand explained: 'Until nowit was commonly thought that the destructiveaction of the ice sheets was not significantenough to eradicate all the fauna and thatdesolate patches were recolonised fromsurrounding areas. But our research confirms thatthe destruction was wholesale with very littlesurviving. Even today calving icebergs ploughingacross the seafloor destroy everything in theirpath. Imagine the impact of ice sheets during theice ages that covered a much wider area in a timeof lower sea levels.'

The team's research will lead to a radicalrethink of the evolutionary history of Antarcticaas the work challenges all the accepted theories.The scientists argue that shallow water animalswere retreating to the deep ocean and thenreturning to recolonise Antartica's shelf seas.Clues to how these two very different communitiescould have achieved this may lie in the animals'DNA.

Sven Thatje continued: 'Our work means that thetext books will need to be rewritten. Our nexttask is to reconstruct what happened inAntarctica during these periods of climate changeand study the genetic and biological linksbetween deep sea and shallow water communities.'



Story Source:

The above story is based on materials provided by British Antarctic Survey. Note: Materials may be edited for content and length.


Cite This Page:

British Antarctic Survey. "Seafloor Creatures Destroyed By Ice Action During Ice Ages." ScienceDaily. ScienceDaily, 19 October 2005. <www.sciencedaily.com/releases/2005/10/051018223429.htm>.
British Antarctic Survey. (2005, October 19). Seafloor Creatures Destroyed By Ice Action During Ice Ages. ScienceDaily. Retrieved October 25, 2014 from www.sciencedaily.com/releases/2005/10/051018223429.htm
British Antarctic Survey. "Seafloor Creatures Destroyed By Ice Action During Ice Ages." ScienceDaily. www.sciencedaily.com/releases/2005/10/051018223429.htm (accessed October 25, 2014).

Share This



More Fossils & Ruins News

Saturday, October 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Deep Sea 'mushroom' Could Be Early Branch on Tree of Life

Reuters - Innovations Video Online (Oct. 24, 2014) Miniature deep sea animals discovered off the Australian coast almost three decades ago are puzzling scientists, who say the organisms have proved impossible to categorise. Academics at the Natural History of Denmark have appealed to the world scientific community for help, saying that further information on Dendrogramma enigmatica and Dendrogramma discoides could answer key evolutionary questions. Jim Drury has more. Video provided by Reuters
Powered by NewsLook.com
Fossil Treasures at Risk in Morocco Desert Town

Fossil Treasures at Risk in Morocco Desert Town

AFP (Oct. 23, 2014) Hundreds of archeological jewels in and around the town of 30,000 people prompt geologists and archeologists to call the Erfoud area "the largest open air fossil museum in the world". Duration: 02:17 Video provided by AFP
Powered by NewsLook.com
Oldest Bone Ever Sequenced Shows Human/Neanderthal Mating

Oldest Bone Ever Sequenced Shows Human/Neanderthal Mating

Newsy (Oct. 23, 2014) A 45,000-year-old thighbone is showing when humans and neanderthals may have first interbred and revealing details about our origins. Video provided by Newsy
Powered by NewsLook.com
Weird-Looking Dinosaur Solves 50-Year-Old Mystery

Weird-Looking Dinosaur Solves 50-Year-Old Mystery

Newsy (Oct. 23, 2014) You've probably seen some weird-looking dinosaurs, but have you ever seen one this weird? It's worth a look. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins