Bertvan:
It matters to those who don't believe the universe is ruled by chance.
Even if there might be a non-random component to evolution/mutation, it does not make much
difference to the science of evolution. If it makes it easier for you to accept a non-random component
then I agree that finding evidence for such could be helpful.
>>Bertvan: Up until now randomness has been such an important part of
the >>dogma that no one has investigated to see if they might be adaptively
directed.
>Pim:
>Why call it a "dogma"?
Bertvan:
I probably should apologize. The word has derogatory connotations. I don't
know what else to call a belief considered beyond question.
Oh one can still question it and if evidence comes available that disproves it, it will have to yield.
The reason that it is "beyond question" right now is because the lack of such evidence.
Definition of neo Darwinism:
>>"3.It postulates that speciation is (usually) due to the gradual
>>accumulation of small genetic changes. This is equivalent to saying that
>>macroevolution is simply a lot of microevolution."
Pim:
>So where lies the boundary between macro and micro-evolution? What forms
this >boundary?
Bertvan:
My personal definition is macro evolution involves mutations leading to the
addition of new organs, systems or body parts, whereas micro evolution is the
shuffling of traits already contained in the gene pool.
And where lies the difference? All are linked to shiffling of traits already in the gene pool, a mutation
here, a mutation there. With the relatively recent work on hox genes we better understand why some
mutations have larger and others smaller impacts.
Bertvan: Chris says such a
distinction is based upon an assumption, and he is correct. However, it is
also an assumption that macro evolution is merely lots of micro evolution.
Sure, an assumption based on a logical consequence. If there appears to be a reason for
a boundary between the two then it should be shown.
BertvaN: No uncontested mutations of macro evolution have been observed.
I wonder what that means. What about the change from single to multi-cellular? Would that be
macro evolution?
Bertvan: The holders of both beliefs can interpret the evidence to support their positions.
It would be interesting though to see why some consider that there is a boundary between the two.
Bertvan: The supporters of a difference between the two, can claim "random mutationa and
natural selection" appears to support stasis rather than novelty.
Actually it supports both.
Bertvan: The supporters of no difference can point out that no alternative mechanism is
presently known. Myself, I consider it healthy that scientists of both views
are now working on the problem.
Could you elaborate on this? Who is working on showing evidence that a boundary exists?