DNA is not dumb
I don't believe in evolution. Actually, let me correct that, I do believe in evolution, but not the common simplified form that is typically taught...
I don't believe in the idea that random point mutations provide the primary thrust for the evolution of species.
I am not arguing for Intelligent Design, nor am I proposing anything counter to current scientific pursuits. I just have trouble believing that the level of complexity we see today could arise out of random mutation in only 4B years.
Instead, I propose that DNA and the reproductive process itself uses DNA adaptation to propogate itself (perhaps adaptation based on variable control of the process of correcting point mutations). Organisms that are able to adapt their DNA more quickly to environmental change will propogate their DNA more effectively. Survival at a genetic level depends on the ability for the organism to evolve. Why leave that entirely to chance?
Again, I am not arguing the mechanism of adaptation is the direct hand of some higher-level force, but the argument instead is that DNA and reproduction are complex processes that may have themselves evolved to enable and support selective adapation. Why would such a critical biological process have remained simplistic when the rest of our biological processes have continued to evolve in complexity?
We still have yet to understand what the vast majority of the genetic code does. Nor can we really explain from an information theory space how the complex structure of an organism arises from DNAs. We don't understand how DNA strands evolve to change in length to incorporate new material. We don't know definitively if viruses can alter the genetic structure in ways that pass down to children. We don't understand how epigenetics plays into evolution or how significant horizatonal gene transfer is in both bacteria or higher-level organisms.
As we begin to understand the mechanisms for genetic evolution, we may start to find that Lamarck wasn't entirely off-base.

4 Comments:
point mutations aren't the only source of evolutionary changes. Something like cross-over during meiosis can be sufficient to cause a different distribution of alleles. As well sex and gene flow also cause genetic variation.
And afterall evolution is just a change in the frequency of alleles within a population from one generation to the next.
And don't underestimate the power of random forces. But mainly point mutations aren't thought to be the main thrust of evolution... gene duplications are more a cause of new genes.
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The bacterial SOS response is an interesting example of how the mechanics of evolution may be more intricate than simple mutation. I'm still not arguing Intelligent Design, just arguing that there is greater complexity to the genetic mechanisms that support evolution than most realize.
"Chemists at the Scripps Research Institute and the University of Wisconsin have uncovered evidence that spontaneous mutations are not the only way in which bacteria acquire resistance to antibiotics. It appears that the bacteria, rather than passively waiting around for a lucky break, may play an active role in their own evolution. The key is in the way antibiotics interact with their bacterial targets... According to Ryan Cirz et al., DNA damage, induced by antibiotics or other stressors, sets off a bacterium's emergency repair mechanism: the SOS DNA damage response." From http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0030221
This website does a good job listing some of the ways DNA correction occurs.
http://www.science.siu.edu/microbiology/micr460/460%20Pages/460.DNArepair.html
Be interesting if we found that in the future cancer and evolutionary genetic mutation were in some way linked.
Interesting article on "junk" DNA.
http://news.bbc.co.uk/2/hi/science/nature/4940654.stm
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