Posted on 03/03/2010 8:17:46 PM PST by SeekAndFind
For 80 years it has been accepted that early life began in a 'primordial soup' of organic molecules before evolving out of the oceans millions of years later. Today the 'soup' theory has been over turned in a pioneering paper in BioEssays which claims it was the Earth's chemical energy, from hydrothermal vents on the ocean floor, which kick-started early life.
"Textbooks have it that life arose from organic soup and that the first cells grew by fermenting these organics to generate energy in the form of ATP. We provide a new perspective on why that old and familiar view won't work at all," said team leader Dr Nick lane from University College London. "We present the alternative that life arose from gases (H2, CO2, N2, and H2S) and that the energy for first life came from harnessing geochemical gradients created by mother Earth at a special kind of deep-sea hydrothermal vent - one that is riddled with tiny interconnected compartments or pores."
The soup theory was proposed in 1929 when J.B.S Haldane published his influential essay on the origin of life in which he argued that UV radiation provided the energy to convert methane, ammonia and water into the first organic compounds in the oceans of the early earth. However critics of the soup theory point out that there is no sustained driving force to make anything react; and without an energy source, life as we know it can't exist.
"Despite bioenergetic and thermodynamic failings the 80-year-old concept of primordial soup remains central to mainstream thinking on the origin of life," said senior author, William Martin, an evolutionary biologist from the Insitute of Botany III in Düsseldorf. "But soup has no capacity for producing the energy vital for life."
In rejecting the soup theory the team turned to the Earth's chemistry to identify the energy source which could power the first primitive predecessors of living organisms: geochemical gradients across a honeycomb of microscopic natural caverns at hydrothermal vents. These catalytic cells generated lipids, proteins and nucleotides giving rise to the first true cells.
The team focused on ideas pioneered by geochemist Michael J. Russell, on alkaline deep sea vents, which produce chemical gradients very similar to those used by almost all living organisms today - a gradient of protons over a membrane. Early organisms likely exploited these gradients through a process called chemiosmosis, in which the proton gradient is used to drive synthesis of the universal energy currency, ATP, or simpler equivalents. Later on cells evolved to generate their own proton gradient by way of electron transfer from a donor to an acceptor. The team argue that the first donor was hydrogen and the first acceptor was CO2.
"Modern living cells have inherited the same size of proton gradient, and, crucially, the same orientation - positive outside and negative inside - as the inorganic vesicles from which they arose" said co-author John Allen, a biochemist at Queen Mary, University of London.
"Thermodynamic constraints mean that chemiosmosis is strictly necessary for carbon and energy metabolism in all organisms that grow from simple chemical ingredients [autotrophy] today, and presumably the first free-living cells," said Lane. "Here we consider how the earliest cells might have harnessed a geochemically created force and then learned to make their own."
This was a vital transition, as chemiosmosis is the only mechanism by which organisms could escape from the vents. "The reason that all organisms are chemiosmotic today is simply that they inherited it from the very time and place that the first cells evolved - and they could not have evolved without it," said Martin.
"Far from being too complex to have powered early life, it is nearly impossible to see how life could have begun without chemiosmosis", concluded Lane. "It is time to cast off the shackles of fermentation in some primordial soup as 'life without oxygen' - an idea that dates back to a time before anybody in biology had any understanding of how ATP is made."
This one will be kicked to the curb too.
Whether the soup is in the microwave or under the broiler it’s still soup....
I CANT HEAR YOU LIFE S A MEANINGLESS ACCIDENT THERES NO GOD LA LA LA LA LA LA LA
BUMP
And how did Earth’s chemical energy come to be?, in fact, how this earth get created? who created hydrothermal vents on the ocean floor?
That looks yummy!
The problem is more like trying to get alphabet soup to run a computer program.
A different line of work using the way DNA changes as a kind of clock suggests Archaea , the germs that live in hot springs , are the oldest living things on Earth. That is consistent with this new theory of how life started.
The day some jackass generates life out of a soup or volcanic vent then I’ll buy into the theory. Until then they can all screw off.
For the record, I believe in creation but accept that it could’ve occurred in whatever fashion was deemed acceptable.
So some cells evolved to form humans? some elephants? some misquitoes? some eagles? etc.
It seems to me that we’d all be evolving towards the same thing. That certainly isn’t the case. If find it hard to believe that there was so many varieties of soup. All these varieties of soup had to be just perfect to form life. Believing that would take a leap of faith.
In the beginning God created the heavens and the earth......
Any other scenario for how it may have come about doesn’t amount to good bathroom wipe!
The energy comes from exploding supernovas which make elements heavier than lead. Solar systems form from a combination of gravity and the natural stickiness of rubbing objects. The decay of Uranium keeps the Earth warm after billions of years. The heat finds lots of ways to escape ,one of them thermal vents on ocean floor.
How did we get here?..
answer: "it just happened".. <<- Paris Hilton answer to most anything..
I’ve been unsuccessful generating life in my ongoing research over many years now; I’ve tried Chicken noodle to no avail, as well as various stews, and chowders (both Manhattan as well as New England). I even have experimented with Borscht, but no life!
You can still have God , he just did things differently from what most religions think he did.
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