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Posted by JP on January 17, 1999 at 14:51:54:
In Reply to: Some points and an ogy posted by Rich on January 17, 1999 at 00:37:34:
: : : 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?
: Three points:
: 1. You have not asked easy questions. Indeed, they are cutting edge questions for evolutionary biologists to tackle. How, indeed, can we go from a prokaryote to a eukaryote. For some good ideas on how this could have happened check out Lynn Margulis's work. She is the originator of the endosymbiont theory, but also considers the origin of the nucleus and chromosomes.
: 2. That you can ask difficult questions in no way lessens the evidence that exists in favor of evolution
: -- fossil record (superb and getting better)
: -- developmental biology (Why do humans have gills?)
: -- Anatomical atavisms (goose bumps in humans)
: -- Molecular biology (DNA similarity between monophyletic groups, i.e. groups of common heritage)
: -- Geology (The time and origin of oxygen atmosphere.)
: -- Evidence for genetic changes in populations (incipient speciation in Rhagoletis pomonella, the apple maggot. Darwin's finches [see any work by Peter and Rosemary Grant].)
: 3. Again, I implore, I beg, I plea, I lay prostrate on the ground beseeching you to produce an alternative to evolution by descent. You are hung up on the biochemcal possibility (you say impossibility) of producing beneficial gene changes through mutation. O.K., legitimate concern, but you deny the existence of evolution based on this? That's not how science works. Science is ogous to a murder mystery. You take all the evidence you can find, and then try and make the best case that you can. The judge and jury, in science, is the scientific community and the trial never ends, in fact the investigation never ends, the case must be tried over and over again. So far the prosecutors have produced huge, mive sets of experiemental, observational and theoretical support for their side (a murder occurred; evolution occurred). The defense has found some gaps in the record, some disagreement about the exact nature of the killing. But the jury (scientific community) agrees, the defense can not disprove that a murder occurred. The jury is not exactly sure how the victim was murdered but there is definitely a corpse.
: The victim: Ignorance. The inability to see a beautiful theory if it bit you, with beatifully evolved jaws, derived from gill arhces, in the flesh that surrounds your atavistic tail bone, the cocyx. (Scientists battle the unknown, the "unknowable", and try to stamp out, murder ignorance)
: The prosecution: scientists
: The Defense: creationsists, exobiologists, other ...ists
: The jury: scientists
: The judge: scientists
: Ethical question: Is there a problem that scientists are the prosecution, the judge and the jury?
You say this case is like a murder, we know there
was one but we don't know exactly how it happened.
I ask you, what jury would convict me it they
thought I had murdered someone yet did not know
exactly how I did it? They would find a body, with
no murder weapon, no theory of how the murder
occured, and no witnesses. How in the world do
you expect I would be found guilty?
And again, the cirstantial evidences you named
are up for question:
1. fossil record: have already been through my arguments
against this.
2. developmental biology: Are you still trying to
p this off as evidence of evolution? Of course,
by any model used, you would expect stages in early
embryonic development to be similar. Since the
embryonic animal begins its existence in each case
as a single celled union of two parental cells,
and the following cell multiplication must operate
for some time in the same type of environment,
and since futhurmore many of the structures developed
would be somewhat similar, it would be natural
that the developing embryos would look much alike
in an early stage of development. Quite early
in developent, however, significant differences
begin to emerge, and these superficial resemblences
give way to the appropriate distinctive characteristics.
The differences are much more pronounced, even in early
stages of development. Incidentally, no competent
evolutionists still use this as evidence for
evolution.
3. Anatomical atavisms: Many of these that are
mentioned , or were mentioned in the past, turned
out to indeed have a function. Man, in his
ignorance and arrogance, sometimes thinks he
knows what all the function of everything is.
And I don't know if you could say that goosebumps
in humans have no function whatsoever.
4. Molecular biology. As I have mentioned before,
this proves nothing about evolution, just in the
case of homologous structures. Again, proving
causation in science on the basis of correlation
is a dangerous premise. Also, what would you
expect the DNA codes of organisms with similar
anatomical parts or morphological similarities to
be, vastly different? If two organisms have arms
that look similar, I would expect the DNA coding
for them to be similar, based on any model used.
5. I'm not a geologist, so I won't comment on this.
However, I always thought it funny that scientists
postulated that the early earth would have just the
right atmosphere to allow life to appear, based on
the fact that life exists and evolution created it.
6. Genetic changes in populations. No one
questions that this can occur, however, this is
not macroevolution. The extrapolation of microevolution
to macroevolution is not valid, and is bad science.