>How is evolution "controversial"? How do you define controversial? To whom
>is it controversial? It is certainly not controversial within the
>scientific community. There are strong disaggreements about certain
>aspects of evolutionary theory, but the great majority of scientists in the
>field have great confidence "common descent" as an overarching framework.
First you imply it is not controversial, then you admit that it is. And
since when are the "great majority" of scientists or people or anything
else the criterion for truth. And since when is an overarching framework
not an issue of philosophy rather than science? So you would admit that
scientists as a body share a philosophical affinity for the grand theory of
evolution, but disagree as to what that means in practical terms? I could
state this in another way by quoting from a well known evolutionary
biologist at Cal Tech whose father dedicated him as a child to proving the
theory of evolution: "I have faith to believe that someday we will
discover an explanation for evolution"
There are a number of scientists who question the validity of the
overriding principles of the theory of evolution without denying the
applicability of the principles of natural selection and speciation. These
are not irrational people.
>The whole distinction between micro and macro evolution is a non-starter in
>my opinion. There is no consensus within the scientific community on what
>the terms even mean, or if they are even valid. It is inappropriate to
>call speciation a "fact" in contrast to "macroevolution" which is a theory
>(read guess). This is an absolutely false dichotomy. The evidence for
>speciation is built up by inference in the same way as evidence for
>patterns of evolutionary change on longer time scales. Speciation is
>accepted even though many questions about mechanism (both at the genetic,
>behavioral, and population levels) remain. In the same way, questions
>remain about mechanisms for change at larger scales while the continuity of
>life is accepted.
I acknowledge your opinion, but do not share it. The lack of concensus in
the scientific community at least is heartening and suggests there is some
validity to the distinction. Scientific concepts are often prioritized
based on the nature of the supportive data. The hierarchy: idea,
hypothesis, theory, law is one example that comes to mind. Using this as a
model, speciation would be a theory or maybe a law (after all a bunch of
Nobel laureates supposedly signed some kind of statement that evolution was
a "fact", and I would hope they were not thinking "macroevolution" when
they signed it!), whereas macroevolution would be a hypothesis or maybe a
theory. They are not at the same level in terms of the data supporting
them or the amount of study they have received.
Certainly if microevolution is the basis for macroevolution, and the two
are manifestations of a single process, then there should be little
disagreement on the mechanism for macroevolution, aince there is general
concensus on the mechanism for microevolution. That this is not the case
should be obvious to all readers of this thread.
Art
http://chadwicka.swau.edu