A group of Finnish scientists suggests a new climate-biosphere interaction mechanism for the underlying processes in a new study, which will be published on February 14, 2007 in PLoS ONE, the international, peer-reviewed, open-access, online publication from the Public Library of Science (PLoS).
The theory invokes cold, ice-containing climates as a key precursor for multicellular life. If the model turns out to be correct, one can assume that complex life might exist also around stars which are more massive and short-lived than the Sun. Since remote sensing of highly reflecting glaciers should be possible, this may help designing future astronomical observation programmes for earthlike extrasolar planets.
Multicellular life was preceded by the cold Neoproterozoic climate 600-800 million years ago which at times produced widespread glaciations. According to the new theory, the coldness was due to low carbon dioxide concentration brought about by strong algal growth in the oceans. The algal growth was maintained by the lack of grazing animals and the ability of cold seawater to mix and transport nutrients efficiently. A moderately high seawater oxygen concentration developed as a byproduct of the algal growth. This enabled diffusive breathing of primitive multicellulars which were larger than their unicellular counterparts. The ability of cold water to contain more dissolved oxygen also helped the multicellulars to thrive.
The diversification of the marine food webs introduced by multicellular predators as well as the moving and burrowing activity of animals on the seafloor contributed to a more efficient decomposition of the algae-produced organic carbon, which slowed the rate of organic carbon sequestration. This in turn increased the atmospheric carbon dioxide level and ended the severe glaciations and the reign of unicellular algae, initiating the development of a modern-type climate.
Andrew Hyde | alfa
Preservation of floodplains is flood protection
27.09.2017 | Technische Universität München
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
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20.10.2017 | Interdisciplinary Research