SCIENTISTS FIND EVOLUTION OF LIFE HELPED KEEP EARTH HABITABLE
Andrew Yee <[EMAIL PROTECTED]> Lawrence Livermore National Laboratory Contact: Anne Stark Phone: (925) 422-9799 E-mail: [EMAIL PROTECTED] FOR IMMEDIATE RELEASE: October 30, 2003 NR-03-10-07 Scientists Find Evolution of Life Helped Keep Earth Habitable LIVERMORE, Calif. -- A trio of scientists including a researcher from the Lawrence Livermore National Laboratory has found that humans may owe the relatively mild climate in which their ancestors evolved to tiny marine organisms with shells and skeletons made out of calcium carbonate. In a paper titled "Carbonate Deposition, Climate Stability and Neoproterozoic Ice Ages" in the Oct. 31 edition of Science, UC Riverside researchers Andy Ridgwell and Martin Kennedy along with LLNL climate scientist Ken Caldeira, discovered that the increased stability in modern climate may be due in part to the evolution of marine plankton living in the open ocean with shells and skeletal material made out of calcium carbonate. They conclude that these marine organisms helped prevent the ice ages of the past few hundred thousand years from turning into a severe global deep freeze. "The most recent ice ages were mild enough to allow and possibly even promote the evolution of modern humans," Caldeira said. "Without these tiny marine organisms, the ice sheets may have grown to cover the earth, like in the snowball glaciations of the ancient past, and our ancestors might not have survived." The researchers used a computer model describing the ocean, atmosphere and land surface to look at how atmospheric carbon dioxide would change as a result of glacier growth. They found that, in the distant past, as glaciers started to grow, the oceans would suck the greenhouse gas -- carbon dioxide out of the atmosphere -- making the Earth colder, promoting an even deeper ice age. When marine plankton with carbonate shells and skeletons are added to the model, ocean chemistry is buffered and glacial growth does not cause the ocean to absorb large amounts of carbon dioxide from the atmosphere. But in Precambrian times (which lasted up until 544 million years ago), marine organisms in the open ocean did not produce carbonate skeletons -- and ancient rocks from the end of the Precambrian geological age indicate that huge glaciers deposited layers of crushed rock debris thousands of meters thick near the equator. If the land was frozen near the equator, then most of the surface of the planet was likely covered in ice, making Earth look like a giant snowball, the researchers said. Around 200 million years ago, calcium carbonate organisms became critical to helping prevent the earth from freezing over. When the organisms die, their carbonate shells and skeletons settle to the ocean floor, where some dissolve and some are buried in sediments. These deposits help regulate the chemistry of the ocean and the amount of carbon dioxide in the atmosphere. However, in a related study published in Nature on Sept. 25, 2003, Caldeira and LLNL physicist Michael Wickett found that unrestrained release of fossil-fuel carbon dioxide to the atmosphere could threaten extinction for these climate-stabilizing marine organisms. Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by the University of California for the U.S. Department of Energy's National Nuclear Security Administration. ============ (10) AND FINALLY: UK SCIENTISTS DEMORALISED BY SCARE-MONGERS AND TECHNO-HYSTERICS The Times, 31 October 2003 http://www.timesonline.co.uk/newspaper/0,,174-874930,00.html By David Charter, Chief Political Correspondent More than 100 leading scientists have made a once-in-a-generation appeal to Tony Blair to save British science from a tide of neglect and abuse that is driving the brightest young brains abroad. The academics, including a Nobel laureate and a host of Royal Society fellows, warned Mr Blair that government attitudes were causing some scientists to flee Britain and demoralising others whose work had been "misrepresented and sabotaged". In a letter delivered to Downing Street yesterday, 114 eminent researchers blamed Mr Blair for a "backward slide" in the climate for debate over technologies such as genetic modification. Britain should lead the world for years to come but instead "we risk seeing technologies lose out to prejudice and procrastination", they claimed. The letter was provoked by a largely hysterical media response to recent GM farm trials, reported as spelling doom for the technology but which in fact showed almost unbridled benefits, the scientists said. Derek Burke, the lead signatory and former chairman of the Government's GM advisory committee, said: "This is a measure of the concern that is out there. A cross-section of the British scientific community feels that evidence that has been carefully and painfully collected is just being swept aside." Professor Burke was scathing of the public debate on GM technology announced by Margaret Beckett, the Environment Secretary, which ran during the summer. "The public meetings were awful," he said. "They were seen as rallies by the green groups and the questions were just hostile. Margaret Beckett was notable by her absence and we felt we were just dropped in it." The letter comes almost 18 months after Mr Blair pledged to break down the strong"anti-science fashion" in Britain. He added that the Government would never give way to misguided protesters who stand in the way of medical and economic advance. However, the scientists do not believe that Mr Blair's words have been backed by actions and want a renewed commitment from the Prime Minister to let the public hear the case for GM. The letter states: "The Government . . . has consistently neglected opportunities to address any of the unsubstantiated assertions about the process of genetic modifications. "Some scientists are leaving the UK but many more are thoroughly demoralised by hostility to the work they do, which is continually misrepresented and even sabotaged. "Those who have contributed many hours to public communication . . . feel undermined by the Government's failure to contradict false claims about 'Frankenfoods' and 'superweeds'." They are also angry that "work on the basic science of genetic engineering and its applications to plants is being scaled down". They conclude: "It is distressing to experience such a backward slide . . . for our students just starting out, it is deeply distressing." One signatory is Mark Tester, head of plant science at Cambridge University, who is heading to the Waite Institute, Adelaide, in search of a safer environment and better funding. He said: "Industry has left in droves and that reduces the options for researchers and students." Another signatory, Professor Christopher Leaver, head of plant sciences at Oxford, has gone ex-directory to escape personal threats as a result of taking part in the GM debate. Professor Alan Malcolm, chief executive of the Institute of Biology, who helped to deliver the letter, said: "We are running experiments to test the (GM) issue, many of which have been dug up, and the Government seems unable to prevent that from happening. We have had court cases where those who dug them up were found not guilty of criminal damage. We are faced with the fact that we cannot get answers to some of the (GM) questions." Names on the letter include Lord Winston, the fertility expert, Dr Tim Hunt, a Nobel prizewinner, and Professor Janet Bainbridge, chairman of the Government's GM advisory committee from 1997 to this year. Dr Claire Cockroft, a Fellow at Cambridge University who helped to deliver the letter, added: "This should be a very exciting time for young scientists, who recognise the opportunity for exploiting the latest advances in plant science to achieve more sustainable agriculture for the benefit of humankind. Unfortunately, current attitudes are undermining their vision." |
