Evolution (Introduction)

by dhw, Saturday, October 09, 2010, 09:07 (4955 days ago) @ David Turell

DAVID: The best sense is made by knowing how evollution developed. There were one-celled forms until shortly before the Cambrian Explosion when mutlcellular froms developed with different body parts. The Ediacarans and Bilatarians were very simple in construction. Therefore life started with unicellar forms, one type, the Archaea, and advanced after 3.2 billion years. Choice No. 1. The advance was mediated in DNA which had coding to guide the advance with the help of natural selection, as the Earth also evolved with differing climates and different arrangement of the land masses. That is Choice 5. Nothing else fits. In comparative anatomy everything changes slightly off a main plan, but is consistent. A horse hoof is a toe, compared to a bear, an elephant or a human. A UI dithering along as in 6 would not be so consistent.
In summary 1 and 5.-There is some sort of misunderstanding here. No. 1 and No. 5 are identical, except that No. 1 is without God (a "self-assembled mechanism"), and No. 5 is with God.-I have a problem with the leap from one-celled forms to multicellular forms with different body parts. Why and how would unicellular forms, which continued to survive as they were, also evolve after all that time into these new forms? "Different body parts" raises the whole question of innovation. If you are going to start with archaia and finish with us, you have to account for the vast range of new and enormously complex organs, systems, connections, none of which were needed by the original archaia or bacteria for their survival.-The structures we share with the rest of the animal kingdom are clear, and to me represent the best evidence we have that there are common ancestors, but we are all a long, long way down the line. It's the gap in your account between the original forms and your "shortly before the Cambrian Explosion" that throws up so many unanswered (unanswerable?) questions. -Many thanks for the brilliant article on antibodies and germ cells that you drew our attention to under "Complexity of Gene Codes". The intricacies of these codes are mind-boggling, and not unrelated to the point I have raised above.