Evolution, survival and adaptation (Evolution)

by dhw, Saturday, September 02, 2017, 12:56 (49 days ago)

I am once more telescoping overlapping threads.

Dhw: (under “Balance of nature, ants…") All forms of life have always depended on some sort of balance, and the balance is constantly shifting, which is why some species have survived and others have died out in the long history of the higgledy-piggledy bush. Thank you for this beautiful illustration of Margulis’s contention that evolution depends on cooperation as well as (if not more than) competition.
DAVID: This is why I question the significance of competition for survival as a major factor.

You questioned the concept of “survival of the fittest”. This is not just a matter of competition. Once again you seem to be equating survival with population density and totally ignoring every other environmental factor that threatens life.

QUOTE: (under “Natures wonders: bacterial adaptation”) "To survive hostile environments, an organism often has to acquire new traits.”
dhw: And yet you keep trying to tell us that survivability plays no role in evolution. Bacteria remain bacteria, but maybe other organisms acquire major new traits for the same reason, and duly become new species.
DAVID: Not that survivability 'plays no role' but a much smaller role than implied by 'survival of the fittest’.

You wrote: “Survival of the fittest is an unproven conjecture.” I consider it pure commonsense that organisms which can cope with the environment survive, and organisms which cannot cope do not survive. Once multicellularity appears, I would suggest that the development of means of survival (and I would add improvement) plays a crucial role in evolution, but perhaps you think that different ways of acquiring food, of catching prey or of defence against predators, and of countering or exploiting changes in the environment only play a small role.

Dhw (under Natural wonders: bacteria can spear amoebas): [...] I do not ask you to agree with my hypothesis – I also have reservations. I only ask you to consider it as a possibility. The mystery does not in any way support your theory that there is a supernatural power which designed flippers before pre-whales entered the water.
DAVID: If major and minor adaptations ae part of the mechanism for change, we have no evidence so far, only small epigenetic DNA changes which can be passed on to descendants. What supports my theory of a supernatural power is the obvious need for visualizing the future form and the design planning that must go into it in order for the change to be accomplished. The DNA of a completely new species may show reference to the past species, but will have very major differences in order to create the new form and function. Only design fits this.

We have had this discussion many times before, but it’s worth repeating since so much else depends on it. After much ado, you agreed some time ago that environmental factors play a major role in evolution. Minor adaptations clearly take place as a RESPONSE to environmental change. There is no visualizing of the future form, and no design planning in advance. You continue to ignore my question concerning the mechanism that makes this possible - i.e. do you think your God dabbled or preprogrammed the changes in the beaks of finches, or did their cell communities accomplish these autonomously? We agree that innovation is far more complex, and that nobody can explain it. Where we do not agree is on the likeliest order of events. You have your God planning major adaptations (innovations) in advance of environmental change, whereas I have my organisms responding to environmental change. Your version requires your God’s advance knowledge of every environmental change that entails innovation, which suggests that he has preprogrammed or manipulated the environment (local and global) as well as the structures of all the creatures that survive the changes. (We’d better leave out the great non sequitur of all this being done for the sake of the human brain!) The complications are enormous, whereas the scenario of life forms RESPONDING to environmental change, either by dying or by adapting or by producing useful new organs to exploit the changes requires only one premise: that they do the designing themselves with an intelligence which your God may have given them in the first place. We know they respond on a minor scale. Perhaps they also respond on a major scale. It’s a hypothesis, but Occam would be delighted with such a simple solution to the mystery.


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