Evolution (Introduction)

by dhw, Saturday, April 18, 2009, 09:13 (5697 days ago) @ George Jelliss

George: dhw talks about "the ability both to adapt to changing environments and to increase complexity" (his emphasis) as if these "abilities" were properties of living things. Humans with consciousness have the ability to adapt themselves to changing conditions. But this is what takes them out of the realm of natural selection. The adapting to changing environments is forced on life from the outside by action of the environment (e.g. colder climate favours those with hairier coats). Complexity arises, as in the haemoglobin example, from simpler components getting combined. These are not driven by some desire within the life-form to become more complex. - In my post I made it clear that I have no problem with the general principle of evolution. My problem is with abiogenesis, and the above is another example of how easy it is to slip from one to the other. Your hairy coat example of adaptation being "forced on life from the outside" is evolution in the form of natural selection. I'm focusing on what you call the "first replicating molecule" and its pals and its immediate descendants. I can't go into the scientific background as David has done, but you have provided the relevant arguments yourself. You say "the code was part of the molecule". That is precisely my point: that the first simple forms of life would not have been changed by new environments unless the code enabling adaptation was already in those first replicating molecules. Therefore we are expected to believe that the first molecules not only chanced upon replication but at the same time chanced upon a code (I called it "ability" but stressed the lack of consciousness, which is the whole point) that would bring about adaptation when the environment changed. - The same applies to complexity. Again you are making the point for me. Of course the life-form isn't driven by some desire to become more complex. There is no desire anywhere, no consciousness, no intention. "Getting combined" glosses over the innovative force of the process: your "first replicating molecules" must also (according to the theory of abiogenesis) have chanced to have within them the code or potential ability to combine mindlessly, blindly, unconsciously with other replicating molecules to produce different, functioning, hitherto non-existent structures so complex that we are immensely proud of ourselves when we understand them. That is what belief in abiogenesis entails. - I asked what performed the producing, assembling etc., and you say I answered "wrongly" that obviously they [the first "simple existing" things] did. Why is that wrong? What else formed the creative combinations if it was not the mindless, blind, unconscious molecules themselves? If they reacted to the environment, that could only be because they had an ingrained code that enabled them to react. Without it, there could have been no adaptation, no combination, no evolution. - Let me repeat yet again that the point in dispute is not evolution but abiogenesis ... i.e. long before there were hairy coats. Perhaps it's no problem for you to believe that chance could bring inanimate globules of matter to life, enable them to replicate, and at the same time endow them with a code which in due course would bring about adaptation and complexity. But I just can't take that leap of faith.