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The Iceland Diaries
for Astrobiology Magazinea Moffett Field (SPX) Feb 12, 2008 In June 2007, Prof. Charles Cockell, Dr. Aude Herrera, Joseph Deeks from the Geomicrobiology Research Group at the Open University and Prof. Stephen Self from the Volcano Dynamics Group at the Open University left England to spend one week in Landmannalaugar, a region near the volcano Hekla in the Southern Highlands of Iceland. Their goal was to collect volcanic rock samples in order to study the bacteria that colonize them. This work, which is funded by the Leverhulme Trust in the UK, required them to fly to Reykjavik and then drive to Landmannalaugar, with a stop on the way in Valahnukar. Aude Herrera recalls their adventures in the first part of her journal.
June 11, 2007: Valahnukar The lava in Valahnukar comes from an eruption of Hekla in 150 A.D., one of the main volcanoes in Iceland. The view is amazing; the field around me is completely devoid of vegetation for as far as I can see. And we can see really far today... We are lucky; the sun shines beyond all our hopes for this time of the year. The ground is covered by dark ash and blocks of volcanic rock. Some of these blocks are old "bombs" ejected from Hekla, although the volcano looks far away from us. They have been here all this time, just to remind us how violent the 150 A.D. eruption actually was. It's fantastic to be here and to imagine that this spectacle would have been common on the early Earth. The general belief among scientists is that the early Earth, prior to 3.8 billion years ago, was a hot volcanic environment in which no living thing could survive. In addition to the hot temperatures, an atmosphere rich in carbon dioxide and other volcanic gases would have defined the environmental conditions. The first traces of life appear in the rock record about 1 billion years after the Earth's formation 4.5 billion years ago. Although travelling back through time to witness the emergence of life is not possible, there exist today a few unique places on Earth that, in some small way, resemble how our planet was in the past. By studying these environments, we might be able to find clues about conditions on the early Earth. Investigations of life in volcanic environments offer a unique window into the past, and a way to investigate life as it could have been in the beginning. Iceland may be the most famous volcanic spot on Earth, with a very high concentration of active volcanoes due to its unique geological conditions. The island has about 130 volcanic mountains, of which 18 have erupted since the settlement of Iceland. Over the past 500 years, Iceland's volcanoes have erupted a third of the total global lava output. Although the early Earth was a harsh place, life may have been able to exist in specific extreme environments. Today, scientists have discovered bacteria and other microbes living in similarly hostile conditions. Indeed, micro-organisms are able to grow in places where nobody would have previously expected (high temperature, high salinity, low nutrient source...). Their ability to adapt to extreme conditions challenges our understanding of microbiology. The question of the origin of life is as old as humankind. A host of philosophers and scientists, from Aristotle (384 - 322 B.C.) to Haldane (1892 - 1964), have described various theories to explain it, and scientists today continue to examine this fundamental and controversial question. For our project, we decided to concentrate our research on the extreme volcanic conditions in Iceland. Our challenge was to understand how bacteria are able to grow, and to determine the methods they use to colonize the volcanic rocks.
June 12, 2007: Landmannalaugar The purpose of my research is to determine the ability of microorganisms to colonize terrestrial volcanic rock, and more specifically to investigate the interactions between rock minerals and microorganisms. Can the silicate content affect microorganism growth? Are there preferential places inside the rock, or maybe on the surface, where microorganisms can find all they need to develop their own habitat and start to colonize the rock? How can microorganisms manage to grow in a glass rock matrix where other organisms are unable to live? For today, we chose to collect samples from obsidian (rhyolitic composition) formed during the A.D. 150 lava flow-forming eruption of Domadalshraun. I feel a bit like an astronaut exploring the martian surface, driving a rover through the barren landscape and collecting rock samples. A major issue when collecting samples in the field, especially for microbial analyses, is to avoid contaminating the samples with our "own" microorganisms. It's important to ensure that microorganisms detected in the rock had been growing in the rocks before we collected them. To protect against contamination, we push samples into a sterile bag by using another rock. By doing this, we avoid touching the samples and they remain protected in the sterile bag until they are analysed in the microbial laboratory, where additional precautions are taken to keep the workspace sterile. Our first day sampling has been a real success and we are coming back to the hut satisfied by our collecting. I'm starting to imagine all the interesting experiments we will be able to run in a few weeks back at the Open University in Milton Keynes. There was some bad news waiting for us in the hut where we planned to stay over the four next days. Because of an "unfortunate technical problem", there will be no hot water for the next four days. And, of course, the showers are outside! Never mind... we are in Iceland, the kingdom of hot springs! This minor incident didn't affect our scientific enthusiasm at all. Indeed, on some occasions we awoke at 7 o'clock in the morning to the sound of Prof. Charles Cockell singing improvised songs about bacteria! Community Email This Article Comment On This Article Related Links Explore The Early Earth at TerraDaily.com
Scientists Rebuild Ancient Proteins To Reveal Primordial Earth's Temperature
Gainesville FL (SPX) Feb 08, 2008Using the genetic equivalent of an ancient thermometer, a team of scientists has determined that the Earth endured a massive cooling period between 500 million and 3.5 billion years ago. Reporting in the journal Nature, researchers from the University of Florida, the Foundation for Applied Molecular Evolution and the biotechnology company DNA2.0 describe how they reconstructed proteins from ancient bacteria to measure the Earth's temperature over the ages. |
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