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Posted by JP on January 17, 1999 at 14:59:47:
In Reply to: Re: macroevolution posted by Muzzy on January 16, 1999 at 23:48:07:
: : : You said:
: : : "As usual, you still fail to comprehend the
: : : difference between microevolution which is
: : : caused by natural selection, and macroevolution
: : : (speciation) which has no known mechanism."
: : : Like many other creationists, you acknowledge that microevolution occurs but not macroevolution. Yet all of us supporting evolution say that macroevolution is just a long series of microevolutionary events.
: : : Why can't a 10 million- or 20 million-year sequence of microevolution involving millions of generations produce macroevolutionary change?
: : Because you have not explained the mechanism for
: : this change to occur. MIcroevolution works on
: : all ready present genes and changes in the
: : frequencies of such and cannot be extrapolated
: : to macroevolution. If you think it can, let me
: : ask you this question: If we started out with
: : a population of bacteria all of which have 1
: : chromosome as there entire genetic makeup, how
: : can simple variations in these genes and selection,
: : after any amount of time, cause organisms with
: : say, 8, 20, or 46 chromosomes to appear? These
: : genes were never present, how then does natural
: : selection work on what is not there?
: The mechanism is natural selection. You have already acknowledged that natural selection is responsible for microevolution. The question is why can't a 10 million- or 20 million-year sequence of microevolution involving millions of generations produce macroevolutionary change?
This is nice, but you still havn't answered my
question. I asked you how natural selection
supposes to take a single bacterium, with one
chromosome, to creatures with 8, 22, or 46
chromosomes. Natural selection works on all
ready present genes, we all know this. Your
reply to this was the answer is natural selection.
How does natural selection do this? Your answer:
natural selection.