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  • Cited by 3
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    This chapter has been cited by the following publications. This list is generated based on data provided by CrossRef.

    Takeuchi, N. Hogeweg, P. and Kaneko, K. 2017. Conceptualizing the origin of life in terms of evolution. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, Vol. 375, Issue. 2109, p. 20160346.

    Korzeniewski, Bernard 2013. Formal Similarities between Cybernetic Definition of Life and Cybernetic Model of Self-Consciousness: Universal Definition/Model of Individual. Open Journal of Philosophy, Vol. 03, Issue. 02, p. 314.

    Hand, Kevin P. McKay, Christopher P. and Pilcher, Carl B. 2010. Spectroscopic and spectrometric differentiation between abiotic and biogenic material on icy worlds. Proceedings of the International Astronomical Union, Vol. 6, Issue. S269, p. 165.

  • Print publication year: 1995
  • Online publication date: October 2009

15 - The RNA World: Life before DNA and Protein



All of the life that is known, all organisms that exist on Earth today or are known to have existed on Earth in the past, are of the same life form: a life form based on DNA and protein. It does not necessarily have to be that way. Why not have two competing life forms on this planet? Why not have biology as we know it and some other biology that occupies its own distinct niche? Yet that is not how evolution has played out. From microbes living on the surface of antarctic ice to tube worms lying near the deep-sea hydrothermal vents, all known organisms on this planet are of the same biology.

Looking at the single known biology on Earth, it is clear that this biology could not have simply sprung forth from the primordial soup. The biological system that is the basis for all known life is far too complicated to have arisen spontaneously. This brings us to the notion that something else, something simpler, must have preceded life based on DNA and protein. One suggestion that has gained considerable acceptance over the past decade is that DNA and protein-based life was preceded by RNA-based life in a period referred to as the ‘RNA world’.

Even an RNA-based life form would have been fairly complicated – not as complicated as our own DNA-and protein-based life form – but far too complicated, according to prevailing scientific thinking, to have arisen spontaneously from the primordial soup.

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  • Online ISBN: 9780511564970
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