Self-Organization, Natural Selection or What?
by BradfordFrom The uniqueness of biological self-organization: challenging the Darwinian paradigm by J. B. Edelmann and M. J. Denton.
Abstract: Here we discuss the challenge posed by self-organization to the Darwinian conception of evolution. As we point out, natural selection can only be the major creative agency in evolution if all or most of the adaptive complexity manifest in living organisms is built up over many generations by the cumulative selection of naturally occurring small, random mutations or variants, i.e., additive, incremental steps over an extended period of time. Biological self-organization—witnessed classically in the folding of a protein, or in the formation of the cell membrane—is a fundamentally different means of generating complexity. We agree that self-organizing systems may be fine-tuned by selection and that self-organization may be therefore considered a complementary mechanism to natural selection as a causal agency in the evolution of life. But we argue that if self-organization proves to be a common mechanism for the generation of adaptive order from the molecular to the organismic level, then this will greatly undermine the Darwinian claim that natural selection is the major creative agency in evolution. We also point out that although complex self-organizing systems are easy to create in the electronic realm of cellular automata, to date translating in silico simulations into real material structures that self-organize into complex forms from local interactions between their constituents has not proved easy. This suggests that self-organizing systems analogous to those utilized by biological systems are at least rare and may indeed represent, as pre-Darwinists believed, a unique ascending hierarchy of natural forms. Such a unique adaptive hierarchy would pose another major challenge to the current Darwinian view of evolution, as it would mean the basic forms of life are necessary features of the order of nature and that the major pathways of evolution are determined by physical law, or more specifically by the self-organizing properties of biomatter, rather than natural selection.
September 29th, 2008 at 10:22 am
In another thread nullasalus writes:
The other thread is, as Bill Clinton is fond of saying, generating more heat than light. The authors, mentioned in this thread, wrote:
Even the example cited- protein folding- entails amino acid sequencing that is traced to DNA. Changes in DNA are analyzed from a selection perspective. But perhaps the authors considered DNA when they wrote that "basic forms of life are necessary features of the order of nature and that the major pathways of evolution are determined by physical law, or more specifically by the self-organizing properties of biomatter, rather than natural selection." Could properties of DNA have come about as a result of self-organization?
Comment by Bradford — September 29, 2008 @ 10:22 am
September 29th, 2008 at 12:25 pm
Organization, whether it is self or other-organized is a teleological, purposeful process. The opposite of random. If "natural selection" doesn't do the organizing, some other force intelligently and purposefully performs the chore. Atheists are perfectly entitled to believe some as-yet-discovered-mechanical process is responsible, but until that mechanism is described in detail, theists are equally entitled to suppose a role for their god. As an agnostic, I believe both are spinning their wheels even speculating aout such things. Life is intelligently organized - organizer unknown.
Comment by Bert — September 29, 2008 @ 12:25 pm
September 29th, 2008 at 12:30 pm
Bert:
Unknown insofar as science is capable of providing identity answers. I agree with the thrust of your comment.
Comment by Bradford — September 29, 2008 @ 12:30 pm
September 29th, 2008 at 12:39 pm
I should have said:
organizer unknowable
Comment by Bert — September 29, 2008 @ 12:39 pm
September 29th, 2008 at 4:54 pm
Bert:
I don't know about that, Bert. Self-organized implies that it happens without external "guidance". When water molecules assemble to form an ice crystal, in what sense is there a purpose?
I just read the paper and although interesting, I think it's a pretty bad paper.
It's true that organisms are to a large extent self-organized. Self-organized in the sense that in many cases the final morphological form is an "attractor" with a really large basin of attraction, not very sensitive to initial conditions. The final 3D shape of a protein doesn't depend much on the precise shape of the initial 1D strand of amino-acids (although chaperones may be required "nowadays"). But do all possible strings of amino-acids self-organize into unique structures, or do some strings have multiple attractors? It might be argued that natural selection tends to choose the ones that have a unique attractor, or at least a single quite "dominating" attractor (prions being examples of where it went wrong).
Comment by Raevmo — September 29, 2008 @ 4:54 pm
September 29th, 2008 at 5:12 pm
Does someone who has the article tell me on what basis they think that "self-organizing systems are easy to create in the electronic realm of cellular automata"? Or even better, could someone send me a copy of the paper (jonathan@bartlettpublishing.com)?
Thanks,
Jon
Comment by johnnyb — September 29, 2008 @ 5:12 pm
September 29th, 2008 at 7:43 pm
I haven't read the paper, but it seems the authors could live with this, Raevmo. Even if some (or most) amino-acid strings have multiple attractors, the property of self-organization would be something over-and-above the normal properties of chemistry or physics. A new level of explanation would have emerged. At least, that seems to be where the authors want to go.
Of course, assuming that this new level of explanation exists, we would need to ask, why does it exist?
Comment by Bilbo — September 29, 2008 @ 7:43 pm