Post Number:#121 August 17th, 2010, 6:53 pm
Alun wrote:I probably should've said environmental pressure on reproductive success, or something similar.
I do not think it means that. The section of the argument where I mention 'reproductive pressure' only means that there is some mechanism which responds to the pressure, not that the mechanism is a decision mechanism, a teleological mechanism, or any mechanism which does not involve those elements. Earlier parts of the argument (having to do with DNA and mutation) offer the evidence of how the mechanism operates--and I take them to show that it operates without deciding to pursue a purpose.
As a scientific theory, NS must give causes for mechanism to happen.
So, my questions were and still are:
What mechanism(s) allow for modification, creation or elimination of specific genes at specific time in a specific environment? (What is this mechanism? Not only giving it a name (environmental/reproductive pressure), but a substance, to describe it)
What is the causation between this environmental pressure and the actual modification of the genome?
If you can't provide answers, your conclusion C1-3) (If a mutation does not help an organism reproduce, there will not be any pressure for that change in genetic information to promulgate.) is simply circular thinking and/or speculation.
Because environmental/reproductive pressure would be defined by: (a mechanism that induce) "a mutation that helps an organism to reproduce".
It lacks at least a premise or pre-conclusion (more like 2) yet to be demonstrated. the existence of: "(environmental pressure is) a cause (here it seems it cannot be a mechanism per se) for a mechanism that allows for a (combination of) gene(s) to change, be modified, created or eliminated".
Am I right?
Also, your C2-4 conclusion: Species can diverge due to reproductive pressure, would be meaningless as there is no definition, no explanation for the nature of this "reproductive pressure".
You can't claim a mechanism to exist if this mechanism is not identified, explained... And if no cause is provided.
It's not really your fault (although you could have noticed it by yourself), it simply means that NS is incomplete at best.
I knew you wanted me to read this thread for something like this to happen... It's not about challenge, it's about another (fresh, logical) pespective... One that allows you to include doubts and hopes in this "theory" (hypothesis, in fact).