Self-Organisation and the Development of Complexity
Here the most important figure is Stuart Kauffman, whose
ideas are most accessibly presented in his At
Home in the Universe (1995).Kauffmans work stems principally out of his analysis of non-linear systems -
the mathematics of chaos, as modelled on the modern computer and applied to
biological systems. In a sense his conclusions complement Stephen Jay Goulds (see
Punctuated Equilibrium and Radical Contingency):
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Goulds stress is that the evolution of higher
organisms is not a matter of inevitable progress to greater sophistication, but
rather that higher systems are always vulnerable to environmental change (most
famously when a massive impact from space, 65 million years ago, led, it is
thought, to the extinction of the dinosaurs).
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Kauffman has made use of the work by Prigogine on
complex chemical systems held far from equilibrium. The surface of the early
Earth contained many such systems (because energy was continually pouring in
from the sun). It is now known that these systems are always likely to give
rise to greater complexity. So the
particularly elaborate systems that are self-replicating cells were, Kauffman
alleges, very likely to arise.Not merely that, but such evolving systems will tend to move to a special
ordered state near to the edge of chaos, representing the ideal balance
between stability and propensity to explore change.
So one of the properties that organisms may be expected to
evolve is evolvability - the capacity to try out new properties without
prematurely losing the benefit of the old.
Although the course of evolution will always be influenced by selection,
and radically altered by any sudden climatic or geological change, it will be
much influenced by the mathematics of self-organisation. Yes, evolution does
depend on all sorts of chances, but also yes, a thermodynamic system like the
surface of the Earth will keep throwing up the possibility of complexity.
An extension of the concept that organisms evolve
evolvability is the perception that they develop information-processing systems
which can analyse the environment and respond not just to stimuli which have
occurred in the past but to conditions not met before. The immune systems of
higher organisms would be an example, but in a sense the clearest case is the
human intellect itself - a product of natural selection which is so versatile
and creative that its activity affects the environment of millions of other
species.
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link | Feedback | Contributed by: Dr. Christopher Southgate and Dr. Michael Robert Negus
Source: God, Humanity and the Cosmos (T&T Clark, 1999)
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