Sometime ago I tossed off a too-quick answer to why I was still
unconvinced the "Macroevolution is Microevolution writ large." Keith
Miller properly took me up on one of my four reasons, as follows:
Burgy wrote>The fact that animals appear in very definite classes, cats,
dogs, elephants, etc. Yes, I know the "niche" arguments, but they are not
really very satisfying.>
I will make a brief reply to the above comment. The fact is, the
boundaries between taxonomic groups are NOT clearly drawn. When you move
back in time toward the time of appearance of a new taxonomic group,
distinctions become less and less clear. It is a very common occurrence
paleontology that there is considerable uncertainty and disagreement
workers regarding the proper classification of early appearing forms.
morphologic features that define recognized living groups do not appear
the fossil record simultaneously. Thus some fossil forms bear some but
all defining characters of a living group, and some bear the defining
characters of more than one distinct taxonomic group. This pattern
characterizes the appearance of many class level groups -- mammals,
birds, reptiles (amniotes), amphibians (tetrapods), bivalves, gastropods,
scaphopods, rostroconchs, etc.
In thinking about this over the past month, while traveling, I conclude
that Keith is right in his criticism. I could argue (as the person who
wrote the butterfly book recently cited by Dembski) that if common
descent is taken as fact, then the researcher will see all evidential
data within that mindset, and be blind to other interpretations. But
somehow I don't find this line of defense satisfying, even if it is
What I was thinking about at the time, and did not express it, was a
gedanken experiment. Suppose the world we inhabited were one in which any
organism could (and often did) mate with any other. Then dog-cats, and
elephant-tiger-apes, and etc. etc. beings would, if not abound, not be
unthinkable, and the sheer variety of living beings, including
human-snail combinations, to take one absurd example, would be
effectively infinite. Now put yourself in such a (terrifying) world and
ask if the variety of living organisms must not be excellent evidence of
"microevolution writ large?" In such a world, the answer would surely be
"yes," and, indeed, overwhelming.
But we do not (thankfully) inhabit such an imaginary world, and,
therefore, I was thinking that the argument must therefore be at least
somewhat weaker here.
But I do acknowledge that it is not a very good argument. Particularly
from one who nearly flunked sophomore (high school) biology and ever
since views its practitioners with awe.
Blessings of the season.
John Burgeson (Burgy)
(science/theology, quantum mechanics, baseball, ethics,
humor, cars, God's intervention into natural causation, etc.)
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