It has been a long time since I read articles or even books on the evolution of life. For me, as a chemist the prebiogenetic stage under reductive atmosphere seemed to be fairly convincing, supported by numerous experimental evidence. (Although lately even this stage was questioned by some scientists arguing that there was enough oxygen even in the reductive atmosphere to counter the assumed abiogenetic processes). Once the cells appeared, biological evolution offers a relatively acceptable scheme to imagine what happened later.
For me the most puzzling is the intermediate phase, where synchronized cycles (described by Tibor Gánti in his chemoton model) developed. Although his model was in principle applicable to enzyme-less systems too, the biggest question for me is the spontaneous (?) appearence of enzymes, and the spontaneous (?) synchronizaton of the nucleic acid and protein synthesis. I heard about the "RNA world" model, but even that does not explain everything. Could you suggest some review of the present status digestable even for an interested non-biologist?
Sir, your question addresses an important aspect of evolution. I am not an expert in the area but i can tell this. Its need based improvisation as cellular life came into being.
And i wish everyone happy new year. May this year be one of scientific enlightenment.
@Joachim: thank you for the references
@Lynn: canned food is rather for maintaining life, but the idea is good. I prefer fresh food, however ...
Gyorgy,
Perhaps you can read my paper "Origin of Evolution versus Origin of Life: A Shift of Paradigm" which is on open access on Google: you have just to type the title.
My hypothesis is that the first catalytic sites appeared on the inner side of the membrane of lipid vesicles composed of heterogeneous amphiphiles.
If you read the paper we could discuss the hypothesis.
Sure. Just look up Pasteur and spontaneous generation on Google..
Try repeating the old experiment on creating amino acids in sealed flasks, with any combination fo simple elements that could have existed on early earth.
Most of these reactions go against entropy. Complex chemicals, if they do form, break down and release their energy.
Dear Marc, thank you for drawing my attention to this interesting article. Right now I had only time to save a copy of itand and to read the introduction. I will surely read it full, but I'm afraid I am not competent do make an evaluation of it, as it inot my field of speciality.
Lynn,
Of course if there is no catalysis such reactions are not favored. In my model there are such catalyses via specific catalytic membrane sites.
it is usually added to the neg-entropy argument that a monotonic entropy increase is "prescirbed" only for closed systems, while the Earth is definitely not a closed system. In a system where there is continuous energy flow (form the Sun) and which is far from equilibrium dissiaptive structures may arise which do exhibit a certain order. (This was the basic assumption of Progogine et al - "Order out of Chaos"). It has not been demonstrated, however, that it is possible to perdict the characteristics and formation rate of such dissipative structures form the distance form equilbirium and from the peripheral conditions. Among others it has not been demonstrated to get cyclic, self-reproductive reactions under such conditions.
Please have a look at my Thermodynamic Dissipation Theory for the origin of life http://www.earth-syst-dynam.net/2/37/2011/esd-2-37-2011.html
There I suggest an Ultraviolet and Temperature Assisted Reproduction (UVTAR) for DNA and RNA based on the photon dissipation properties of these molecules. I also suggest that the first amino acids were those of aromatic rings (tyrosine, tryptophan, phenylalanine, and histidine) since these also absorb strongly in the UV and they have strong chemical attraction to their anti-codons on RNA.
Hi Gyorgy,
My work on the hydrolysis of phosphate ester in the aged inorganic iron solution may answer your questions,. I believe that the inorganic enzyme, as I suggested, more and more were reported recently provide solid evidence that life was from inorganic to organic, instead of the RNA world.
Hydrolysis of Glucose-6-phosphate in Aged, Acid-Forced Hydrolysed Nanomolar Inorganic Iron Solutions — An Inorganic Biocatalyst?
Article in RSC Advances 2(1):199-208 · January 2012
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