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Evolution holes

  1. Sep 29, 2005 #1
    Where are the current unknowns in the evolution timeline?
    It is my knowledge that the progressions from gaslike "soup" to amino acids is believed to have been caused by intense lightning and UV radiation. But the mystery is how we went from amino acid to protein? Are there any other unknowns in this theory.
  2. jcsd
  3. Sep 29, 2005 #2


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    These questions about the origins of life are not part of the theory of evolution. Evolution assumes the ability of organisms capable of reproducing with variation.

    There are a number of theories about the origin of life. The lightning explanation was suggested by Miller's early experiment showing that a flask of "chemical soup" could form amino acids under the effect of an electric arc. But the lighning is not thought to have been very probably in prebiotic earth's atmosphere; life is involved in putting water vapor into the atmosphere which would, at least on simple models, be requied for lightning to form.
  4. Sep 29, 2005 #3


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    It depends on what you're asking about.
    If you demand, say, a full historical record of all life-forms on Earth, and hence, the complete history of evolution, then that story will never appear.
  5. Sep 29, 2005 #4
    You seem to be referring to the Miller Urey experiments.

    There are several other scenarios that are possible. One involves self-assemble of organic molecules on a type of clay found near lakes. Another involves chemistry at deep sea vents.

    The original bio-molecule was more likely RNA or ribo-proteins (not sure if I nailed that name) --- it can replicate *and* perform catalysis. Protein and DNA each only do one of these, to our knowledge.

    Amino acids can be catalyzed to form proteins without the aid of enzymes, but any "meaningful" string of amino acids would need to be directed by a somewhat stable code (RNA).

    Also - go to pubmed and search for abstracts using terms like: prebiotic chemistry" "origins of life" etc. You should find lots of reviews and other types of information.
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