Changes

[[File:Francis_Crick.jpg|thumb|right|thumbnail|200px|[[Francis Crick]] ]]

[[File:Francis_Crick.jpg|thumb|right|thumbnail|200px|[[Francis Crick]] ]]

The attempt to explain the origin of life faces numerous difficult problems which is why the theory has not fared well in recent times:

The attempt to explain the origin of life faces numerous difficult problems which is why the theory has not fared well in recent times:

#Cross contamination of impure reactants and products in the natural world inhibit further formation of more complex biomolecules from simple ones, separation of necessary compounds generally does not occur in nature, any functional molecule that could even form would get terminated by the majority of nonfunctional material it emerged from, and self-organization is not a intrinsic property of biological matter.<ref name="NAS" />

#Laboratory experience from centuries of organic chemistry indicate that cross contamination of impure reactants and products in the natural world inhibit further formation of more complex biomolecules from simple ones, separation of necessary compounds generally does not occur in nature, any functional molecule that could even form would get terminated by the majority of nonfunctional material it emerged from, and self-organization is not a intrinsic property of biological matter.<ref name="NAS" />

#'''Chicken or the Egg problem regarding [[DNA]] and [[protein]]s''': John Horgan wrote: "Many investigators now consider nucleic acids to be much more plausible candidates for the first self-replicating [[molecule]]s. The work of [[James Watson|Watson]] and [[Francis Crick|Crick]] and others has shown that proteins are formed according to the instructions coded in DNA. But there is a hitch. DNA cannot do its work, including forming more DNA, without the help of catalytic proteins, or [[enzyme]]s. In short, proteins cannot form without DNA, but neither can DNA form without proteins. To those pondering the origin of life, it is a classic chicken-and-egg problem: Which came first, proteins or DNA?" - (John Horgan,[science writer], "In The Beginning...," ''[[Scientific American]]'', Vol. 264, No. 2, February 1991, pp.&nbsp;100–109, p.&nbsp;103)"<ref name="members.iinet.net.au"/>

#'''Chicken or the Egg problem regarding [[DNA]] and [[protein]]s''': John Horgan wrote: "Many investigators now consider nucleic acids to be much more plausible candidates for the first self-replicating [[molecule]]s. The work of [[James Watson|Watson]] and [[Francis Crick|Crick]] and others has shown that proteins are formed according to the instructions coded in DNA. But there is a hitch. DNA cannot do its work, including forming more DNA, without the help of catalytic proteins, or [[enzyme]]s. In short, proteins cannot form without DNA, but neither can DNA form without proteins. To those pondering the origin of life, it is a classic chicken-and-egg problem: Which came first, proteins or DNA?" - (John Horgan,[science writer], "In The Beginning...," ''[[Scientific American]]'', Vol. 264, No. 2, February 1991, pp.&nbsp;100–109, p.&nbsp;103)"<ref name="members.iinet.net.au"/>

#Complexity of the [[cell]]: [[Molecule|Molecular]] [[biology|biologist]] Michael Denton wrote regarding the complexity of the cell: "To grasp the reality of life as it has been revealed by [[molecular biology]], we must magnify a [[cell]] a thousand million times until it is twenty [[kilometer]]s in diameter and resembles a giant airship large enough to cover a great city like [[London]] or [[New York City|New York]]. What we would then see would be an object of unparalleled complexity and adaptive design. On the surface of the cell we would see millions of openings, like the port holes of a vast space ship, opening and closing to allow a continual stream of materials to flow in and out. If we were to enter one of these openings we would find ourselves in a world of supreme technology and bewildering complexity... Is it really credible that random processes could have constructed a reality, the smallest element of which-a functional [[protein]] or [[gene]] - is complex beyond our own creative capacities, a reality which is the very antithesis of chance, which excels in every sense anything produced by the intelligence of man?"<ref>Michael Denton, Evolution: A Theory in Crisis, Burnett Books, London, 1985, pages 328 and 342</ref>

#Complexity of the [[cell]]: [[Molecule|Molecular]] [[biology|biologist]] Michael Denton wrote regarding the complexity of the cell: "To grasp the reality of life as it has been revealed by [[molecular biology]], we must magnify a [[cell]] a thousand million times until it is twenty [[kilometer]]s in diameter and resembles a giant airship large enough to cover a great city like [[London]] or [[New York City|New York]]. What we would then see would be an object of unparalleled complexity and adaptive design. On the surface of the cell we would see millions of openings, like the port holes of a vast space ship, opening and closing to allow a continual stream of materials to flow in and out. If we were to enter one of these openings we would find ourselves in a world of supreme technology and bewildering complexity... Is it really credible that random processes could have constructed a reality, the smallest element of which-a functional [[protein]] or [[gene]] - is complex beyond our own creative capacities, a reality which is the very antithesis of chance, which excels in every sense anything produced by the intelligence of man?"<ref>Michael Denton, Evolution: A Theory in Crisis, Burnett Books, London, 1985, pages 328 and 342</ref>