Professor Large and Professor Maslennikov on the hunt for suitable black shales in Siberia Courtesy of University of Tasmania
Posted on 02/25/2014 10:11:29 AM PST by null and void
Professor Large and Professor Maslennikov on the hunt for suitable black shales in Siberia Courtesy of University of Tasmania
Tasmanian researchers have revealed ancient conditions that almost ended life on Earth, using a new technique they developed to hunt for mineral deposits.
The first life developed in the ancient oceans around 3.6 billion years ago, but then nothing much happened. Life remained as little more than a layer of slime for a billion years. Suddenly, 550 million years ago, evolution burst back into action — and here we are today. So, what was the hold-up during those ‘boring billion’ years?
According to University of Tasmania geologist Professor Ross Large and his international team, the key was a lack of oxygen and nutrient elements, which placed evolution in a precarious position. “During that billion years, oxygen levels declined and the oceans were losing the ingredients needed for life to develop into more complex organisms.”
By analyzing ancient seafloor rocks, Ross and his Australian, Russian, US and Canadian colleagues were able to show that the slowdown in evolution was tightly linked to low levels of oxygen and biologically-important elements in the oceans.
“We’ve looked at thousands of samples of the mineral pyrite in rocks that formed in the ancient oceans. And by measuring the levels of certain trace elements in the pyrite, using a technique developed in our labs, we’ve found that we can tell an accurate story about how much oxygen and nutrients were around billions of years ago.”
Their research will be published in the March 2014 issue of the journal Earth and Planetary Science Letters.
“We were initially looking at oxygen levels in the ancient oceans and atmosphere to understand how mineral deposits form, and where to look for them today. That’s a focus of the Centre for Ore Deposit and Exploration Science (CODES), which we established with ARC and industry funding at UTAS in 1989,” Ross explains. “But the technology we have developed to find minerals can also tell us much about the evolution of life.”
After an initial burst of oxygen, the study plots a long decline in oxygen levels during the ‘boring billion’ years before leaping up about 750-550 million years ago.
“We think this recovery of oxygen levels led to a significant increase in trace metals in the ocean and triggered the ‘Cambrian explosion of life’. We will be doing much more with this technology, but it’s already becoming clear that there have been many fluctuations in trace metal levels over the millennia and these may help us understand a host of events including the emergence of life, fish, plants and dinosaurs, mass extinctions, and the development of seafloor gold and other ore deposits,” says Ross.
The Centre for Ore Deposit and Exploration Science was established as an Australian Research Council Centre of Excellence. The study has been funded by the Australian Research Council and is collaboration with the Russian Academy of Science, University of California, the Yukon Geological Survey, Geological Survey of Western Australia, Flinders University, Museum Victoria, and Mineral Resources Tasmania.
Democrats were in charge, obviously................
How is it possible serious researchers can be so stupid regarding cause and effect? I hope it’s only the reporting that is so bad.
Plants are the prevalent life forms. To them, carbon dioxide is life, and oxygen is nothing more than a dangerous waste product. When plants prosper, oxygen levels rise. Attributing an increase in life to a rise in oxygen... my brain wants to explode!
Tasmanian researchers have revealed ancient conditions that almost ended life on Earth...
Well, we know one thing for sure. If life on earth HAD ended, it would have been George W. Bush's fault...
from what I have read, the build up of green sludge and algae or that type of plant life in the oceans, and then dying, due to the over-all loss of oxygen on the planet, resulted in the majority of our oil deposits. It settled to the bottom and formed miles deep layers of bio mass, which became the oil.
not a scientist, it’s just what I have read.
My brain wants to explode at your false conclusions.
Before there were plants there were single celled organisms. These single celled organism likely grew a dependence on an ocean that was saturated with Oxygen, when the oxygen crashed the majority of these organisms disappeared. Those that survived developed mechanisms to utilize available energy sources such as iron oxide and CO2. Giving rise to more complex organisms.
Kinda hard to get solid scientific proof for this, eh? So it’s a way of getting recognition and getting in the news.
the key was a lack of oxygen and nutrient elements, which placed evolution in a precarious position. “During that billion years, oxygen levels declined and the oceans were losing the ingredients needed for life to develop into more complex organisms.”
What is this nonsense? Times of hardship and shortage are exactly when natural selection kicks into high gear, selecting the most fit organisms even more aggressively than usual. If anything would stall natural selection, it would be an extended period of plenty, not a shortage.
Sounds like the later. Interesting that both types depend on each other, now. Well, O2 life relies on plants to produce O2.
“Plants are the prevalent life forms. To them, carbon dioxide is life, and oxygen is nothing more than a dangerous waste product.”
Plants do respire oxygen at night though, so it’s not really a dangerous waste product.
I don’t know what any of that is supposed to mean, but I do know that “Cloister the Stupid” would make a great Freeper name!
You’re the ignorant one. Molecular oxygen is the 2nd most strongly reducing molecule in the cosmos. It cannot long persist in any environment which has not been already nearly completely reduced. The initial atmosphere, therefore, had almost zero oxygen and high concentrations of carbon dioxide.
For millenia, only chemotrophic organisms existed, held in meager numbers by the organism’s own inability to generate their own food. The atmosphere became rich in oxygen when single-celled autotrophs emerged, which consumed CO2 and generated molecular oxygen. At first, their waste product, oxygen, continued to react with the still only partially reduced environment, and be removed from the system. But eventually, the oxygen began to build up and poison nearly the entire first-generation biosphere. Fortunately, before the autotrophs were destroyed, an equilibrium between one one hand natural and chemotrophic reduction and on the other autotrophic oxygen production was reached. Thus the autotrophs survived long enough for the world’s first oxidizing autotrophs to emerge.
Ok, so life evolved 3.6 billion years ago, then sat around being boring and slimy until 550 million (0.6 billion) years ago. The article repeatedly states that this boring epoch (3.6 - 0.6) was “one billion” years. Someone’s math is a bit off. Or maybe it’s fedgov accounting (”a few billion here, a few billion there, what’s the difference”)?
>> Plants do respire oxygen at night though, so it’s not really a dangerous waste product. <<
Well, yes and no:
The plants that SURVIVED the great oxygen poisoning are not poisoned by oxygen, tautologically. But 99.9999999999999% of all the plants which existed at the time went extinct. (By plants, I mean autotrophs, whether procryotic, eucaryotic or multicellular. With 3-, 5- and even 8-kingdom models, some people think you mean “Kingdom Plantae” when you say “plants.” Plantae were not around.)
Also, only a very small portion of plants respire oxygen at night. These are called “C-4” plants, although they are disappointingly not very explosive.
>> It cannot long persist in any environment which has not been already nearly completely reduced <<
Any first-semester chemistry student will recognize I wrote “reduced” when I obviously meant “oxidized.”
Red Dwarf was a BBC science fiction comedy. A science fiction comedy??? Does that even work? Oh yeah, BIG time.
It ran for eight seasons, and had a subsequent movie and a few books.
It skewers so much of modern life that the saying around the nully household is “If it exists, there is a Red Dwarf of it.”
There are DVDs available, and I believe it’s on Netflix
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.