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``Autopoiesis'' is the explanatory principle for the organization of living systems, a concept directly applicable to the problematic issues surrounding the origins of life. Because it provides criteria by which a system may be judged as living, autopoiesis can be used to characterize a minimal living system. Once these defining characteristics have been established, we can extrapolate the conditions which would have made possible the emergence of earliest life. Because autopoiesis is a principle of organization, it provides a definition of living systems not restricted to specific molecules or structures - that is, to those nucleic-acid/protein/lipid cellular life forms with which we are familiar. Autopoiesis provides the conceptual and systematic framework within which any living system may be identified. In examining living systems, then, autopoiesis gives us a literally ``meta-physical'' view of life.
Fleischaker, G. R.; Margulis, L.
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The two biggest mysteries of evolutionary biology is how complex cells can emerge from a chemical matrix , then form into muti-cellular animals. Chemistry alone cannot explain how these complex circular systems form in the first place.
The fossil record of the Cambrian shows multi-cellular life appears very complex at the beginning 535 million years ago. Some may assume life has became more complex since, but actually we have less phylum level body plans now, than then.
These two rings of self organizations, (autopoiesis) from the cell to the macro-physiology it is embedded within seems to more like a nonlinear event, rather than a gradual progression.
My point is this: Life, and the evolution of life, cannot be defined though strictly biochemical constraints. Evolution, reproduction, autopsies, and origins can only be understood more fully though the lens of quantum mechanics, nonlinear dynamics and chaos. Biological system are made up of chemical components, but contain organizational dynamics more akin to the cycles and pulses of the underlying dynamics of the quantum world.
Consider the following:
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Chaos and Complexity
One of the themes straddling both biological and physical sciences is the quest for a mathematical model of phenomena of emergence (spontaneous creation of order), and in particular adaptation, and a physical justification of their dynamics (which seems to violate physical laws).
The physicist Sadi Carnot, one of the founding fathers of Thermodynamics, realized that the statistical behavior of a complex system can be predicted if its parts were all identical and their interactions weak. At the beginning of the century, another French physicist, Henri Poincare`, realizing that the behavior of a complex system can become unpredictable if it consists of few parts that interact strongly, invented "chaos" theory. A system is said to exhibit the property of chaos if a slight change in the initial conditions results in large-scale differences in the result. Later, Bernard Derrida will show that a system goes through a transition from order to chaos if the strength of the interactions among its parts is gradually increased. But then very "disordered" systems spontaneously "crystallize" into a higher degree of order.
First of all, the subject is "complexity", because a system must be complex enough for any property to "emerge" out of it. Complexity can be formally defined as nonlinearity.
The world is mostly nonlinear. The science of nonlinear dynamics was originally christened "chaos theory" because from nonlinear equations unpredictable solutions emerge.
A very useful abstraction to describe the evolution of a system in time is that of a "phase space". Our ordinary space has only three dimensions (width, height, depth) but in theory we can think of spaces with any number of dimensions. A useful abstraction is that of a space with six dimensions, three of which are the usual spatial dimentions. The other three are the components of velocity along those spatial dimensions. In ordinary 3-dimensional space, a "point" can only represent the position of a system. In 6-dimensional phase space, a point represents both the position and the motion of the system. The evolution of a system is represented by some sort of shape in phase space.
The shapes that chaotic systems produce in phase space are called "strange attractors" because the system will tend towards the kinds of state described by the points in the phase space that lie within them.
The program then becomes that of applying the theory of nonlinear dynamic systems to Biology.
Inevitably, this implies that the processes that govern human development are the same that act on the simplest organisms (and even some nonliving systems). They are processes of emergent order and complexity, of how structure arises from the interaction of many independent units. The same processes recurr at every level, from morphology to behavior.
Darwin's vision of natural selection as a creator of order is probably not sufficient to explain all the spontaneous order exhibited by both living and dead matter. At every level of science (including the brain and life) the spontaneous emergence of order, or self-organization of complex systems, is a common theme.
Koestler and Salthe have shown how complexity entails hierarchical organization. Von Bertalanffi's general systems theory, Haken's synergetics, and Prigogine's non-equilibrium Thermodynamics belong to the class of mathematical disciplines that are trying to extend Physics to dynamic systems.
These theories have in common the fact that they deal with self-organization (how collections of parts can produce structures) and attempt at providing a unifying view of the universe at different levels of organization (from living organisms to physical systems to societies).
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04-01-2007
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