Abiogenesis
From RationalWiki
Abiogenesis is the process by which a living organism arises naturally from non-living matter. Scientists speculate that life may have arisen as a result of chemical processes to produce self-replicating molecules. One hypothesis revolves around a lightning strike in a primordial soup consisting of all kinds of interesting organic molecules floating around in the shallow warm seas of the primitive earth. Experiments have demonstrated that these conditions can produce some complex molecules that could be considered the "building blocks of life", but so far no experiment has produced life itself. Another hypothesis centers on chemical reactivity around hydrothermal vents. Give those crazy scientists a half billion or so years to play,[1] though, and they might do just as well as nature once did!
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[edit] Evolution and abiogenesis
Abiogenesis and evolution are two different things. The theory of evolution says absolutely nothing about the origin of life. It merely describes the processes which take place once life has started up. There may also be multiple pathways to producing naturally occurring "life". Depending, of course, on the definition of life.
This is something that Ben Stein is apparently willfully ignorant of.
[edit] Artificial abiogenesis
Craig Venter claims to be on the point of being able to insert a wholly artificial chromosome into a bacterial cell and thus create the first artificial life form. While not complete and natural abiogenesis it certainly moves a long way in that direction.[2]
[edit] Creationists and abiogenesis
Certain creationists correctly point out that abiogenesis must have taken place at some point to begin the process of evolution. They then attempt to use this premise to "disprove" evolution, claiming that Francesco Redi disproved abiogenesis in 1668.
In fact, Redi did no such thing. He only proved that maggots do not form spontaneously on hunks of raw meat.
The fact that the original organisms posited by abiogenesis are of the kingdom Archaea (and are therefore significantly less complicated than maggots), and that they had millions (or billions) of years on a planetary surface full of organic molecules that was being constantly bombarded by cosmic rays and racked by volcanic eruptions during which to arise, does apparently not occur to most creationists. This leads to stupid ideas like the Peanut Butter Argument[3].
In the 1950s, several experiments by Stanley Miller and Harold Urey verified that the natural formation of amino acids, components of DNA, and other organic compounds out of inorganic materials was possible under the atmospheric conditions of Primordial Earth. [4]
[edit] Oil
Main article: Abiotic oil
Oil is now understood to be biogenic in origin, not abiogenic. A hypothesis that oil was abiogenic in origin was popular in the Soviet Union until the 1980s. The abiogenic origin hypothesis proposed that oil formation results from chemical reactions taking place within the earth, and that oil is thus continually replenished and not a fossil fuel. A few (astronomer Thomas Gold until his 2004 death, and Jack Kenney) have continued to promote the abiogenic origin hypothesis.
[edit] See also
[edit] Footnotes
- ↑ Because that's roughly how long it took to form those initial molecules after things cooled down a bit
- ↑ http://www.guardian.co.uk/science/2007/oct/06/genetics.climatechange
- ↑ http://www.godtube.com/view_video.php?viewkey=ab476a318839606743bd
- ↑ http://www.issol.org/miller/miller1953.pdf
