More Denton: Reply to Tony (Introduction)

by dhw, Thursday, July 30, 2015, 18:41 (3195 days ago) @ David Turell

Dhw (to Tony): This is a tricky conversation, as my comment was directed towards David, who believes in common descent, as I do. By “speciation” I only meant that the different species appeared, and as there are no known precursors, David and I must assume that the changes to existing organisms took place during the 5-10 million years.-DAVID: Please do not speak for me as I do not accept your view of the Cambrian. The various specimens from that time show complete intact animals of various types, but no variation within the types as if small adjustments were being made over a 5-10 million years period as you imply.-I'm sorry, but this is a complete misunderstanding on two counts. Firstly, you have stated explicitly that you believe in common descent, which means that the new Cambrian organisms must have sprung from existing organisms, and whatever innovations took place did so within the period of 5-10 million years. That's what I meant by the changes. Secondly, I have never stated or even implied that the new species resulted from small adjustments over a period of time. I have repeated over and over again that the intelligent mechanism would explain the “explosion”, as it would explain why organisms were able to produce functioning innovations. You even quoted me in your answer yesterday under “Reply to David”:-dhw: My (hypothetical) intelligent mechanism exploits the opportunities provided by a new environment. A sudden major change in the environment could lead to a sudden burst of major innovations, but innovations that don't work straight away won't survive. That is the simple logic.-A sudden burst of major innovations does not mean small changes spread over 5-10 million years, and “straight away” does not mean 5-10 million years later!