Increasing complexity
Early organisms are likely to have been severly limited in the volume of
information they can reliably store in their genomes.
The question arises as to how they can do very much in the
way of synthesizing error correction machinery - when they
cannot become complex enough to specify it.
A possible resolution to this dilemma arises in the form of multiple species.
If compounds A, B,
C, D, E
and F are needed in order to synthesize some piece of
complex equipment, one might think that organisms are stumped if they can only
snthesize two components before they face a mutational meltdown due to a high
error rate.
A possible resolution to this dilemma arises in the form of multiple species.
We can envisage, one species synthezizing A and B,
another synthesizing C and D
and a third synthesizing E and F.
If these species coesxisted in the same environment, all the components
necessary for the synthesis would be available in solution.
While this is a fairly obvious point, it suggests that even
small simple self-replicating systems with relatively high
error rates may be relevant to the origin of life.
Even if such organisms were not themselves capable of much
in the way of complexity they may nontheless contain the
seeds of more complex systems.
References
The first expression of this idea I have encountered is due to Gordon Allen:
Genetic information could be integrated extrinsically for simplest life forms;
tim@tt1.org | http://originoflife.net/
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