More about how evolution works; stasis (Evolution)

by dhw, Monday, October 19, 2015, 11:11 (3106 days ago) @ David Turell

dhw: I can't follow your argument. Earth's changes explain why 90% of species are extinct: they died when they couldn't adapt. Earlier you complained that my hypothesis didn't explain “broad evidence of stasis, such as 250 million years of unchanged trilobites or 70 million-year old unchanged coelacanths.” Dinosaurs ruled the earth for about 160 million years, but died out when they couldn't cope with new conditions. What is there to explain?
DAVID: Aren't 'ancient forms that never change most unusual'? Of course trilobites and dinosaurs died out, but bacteria didn't through 'snowball' Earth, palm trees in the Arctic, ice ages, etc. To me this means certain organisms are not meant to die, but I forget, you don't want to look for purpose in evolution.-I see it the other way: you want to look for a special purpose in evolution, whereas I interpret the higgledy-piggledy comings and goings as evidence that there is no overriding purpose: only individual purposes, as organisms seek to survive and/or improve. This is mirrored by the evolution of human society, in which each individual also seeks to survive and/or improve, and innovations for improvement lead to colossal transformations: new species, ways of life, natural wonders in the animal world; new ways of life and technological wonders in the human world.
 
dhw: I am not implying that adaptation leads to speciation, but that the same mechanism may also exploit new conditions in order to create new structures that lead to improvement (and so to speciation). 
DAVID: That sentence runs in circles: 'not implying adaptation leads to speciation'....'and so to speciation'. -No circle here. I am trying to distinguish between adaptation, which leaves the species intact, and innovation (new structures) which leads to new species. I am suggesting that the same autonomous “brain” of the cell community is responsible for both processes.
 
dhw: You keep repeating the same objection, and I keep repeating the same answer. The changes HAVE to be jumps (hence no fossils) or the organisms won't survive. 
DAVID: And my objection is the same. The gaps in the fossil record require the engineering of new forms so that all the new parts are coordinated in their functions. The whale series of eight or nine steps is a wonderful example of the impossibility of your thesis. Those 'intelligent cell communities' can just think of everything and make the jumps.-The whale series is a wonderful example of how my hypothesis works. Each step takes place in existing organisms that innovate in accordance with what the environment allows. And of course the cell communities must adjust so that the new parts are coordinated. That would also apply if your own hypotheses were correct: either God dabbled to ensure the coordination, or his 3.8-billion-year computer programme passed on the instructions for all the cell communities to coordinate once environmental changes triggered his special 8-9 step programme for the production of whales, even though his purpose was to produce humans!