>Reflectorites
>
>On Mon, 16 Oct 2000 14:20:26 -0500, Susan Cogan wrote:
>
>SB>David Bradbury (or Stephen Jones, I couldn't find the original post):
>
>It was me who posted it originally
>
>>DB>2) Your following citation also brings up another interesting,
>>but unrelated
>>>thought.
>>>
>>>SJ>"Despite a close watch, we have witnessed no new species emerge
>>>in the wild in
>>>>recorded history. Also, most remarkably, we have seen no new animal
>>>>species emerge in domestic breeding. That includes no new species of
>>>>fruitflies in hundreds of millions of generations in fruitfly
>>>>studies, where both
>>>>soft and harsh pressures have been deliberately applied to the
>>>>fly populations to
>>>>induce speciation. And in computer life, where the term "species"
>>>>does not yet
>>>>have meaning, we see no cascading emergence of entirely new kinds
>>>>of variety
>>>>beyond an initial burst. In the wild, in breeding, and in
>>>>artificial life, we see
>>>>the emergence of variation. But by the absence of greater change, we also
>>>>clearly see that the limits of variation appear to be narrowly
>>>>bounded, and often
>>>>bounded within species. ... No one has yet witnessed, in the
>>>>fossil record, in real
>>>>life, or in computer life, the exact transitional moments when
>>>>natural selection
>>>>pumps its complexity up to the next level. There is a suspicious
>>>>barrier in the
>>>>vicinity of species that either holds back this critical change
>>>>or removes it from
>>>>our sight. (Kelly K.,"Out of Control: The New Biology of Machines", 1995,
>>>>p475)
>
>[...]
>
>SB>I suspect the Kelly quote is out of context,
Stephen:
>On what basis does Susan say this. Has she read the book?
no, I'm looking for it, though. The reason I think it's out of
context is because Gould says something similar. What is *always*
trimmed by the person quoting its the fact that transitions are rare
at the species level in the fossil record (they exist, there just
aren't many) but they are abundant *above* the species level. It's
possible that Kelly is simply wrong.
>SB>but if not perhaps you
>>or Kelly should do some facing up to reality:
>>
>>This article is on page 22 of the February, 1989 issue of
>>Scientific American.:
>>"Three species of wildflowers called goatsbeards were introduced to
>>the United States from Europe shortly after the turn of the century.
>>Within a few decades their populations expanded and began to
>>encounter one another in the American West. Whenever mixed
>>populations occurred, the specied interbred (hybridizing) producing
>>sterile hybrid offspring. Suddenly, in the late forties two new
>>species of goatsbeard appeared near Pullman, Washington. Although the
>>new species were similar in appearance to the hybrids, they produced
>>fertile offspring. The evolutionary process had created a separate
>>species that could reproduce but not mate with the goatsbeard plants
>>from which it had evolved."
>>
>>this is from the talk.origins archive which has two FAQ files that
>>list observed instances of speciation. Here is one of them:
>>http://www.talkorigins.org/faqs/speciation.html
>
>If this is what Kelly meant by "species" then he is indeed wrong on this
>particular point.
>
>But it is possible he regards these as just "variation". There are other
>examples too of speciation among plants, but the cases are so trivial
>(remaining within the same genera) that they serve to underline the *real*
>problem that:
*all* evolution is at the species level. Anything above that is an
accumulation of changes so that the decedent no longer resembles the
ancestor enough to be classified in the same genus. The reason the
speciation events described in the FAQ are speciation and not
variation is because the daughter plant cannot interbreed with the
parent. At least for sexually reproducing organisms you can sometimes
use that to discern speciation.
>
>See above. How many examples does the FAQ list where: "natural selection
>pumps its complexity up to the next level" (i.e. above the species level)?
the "pumping its complexity" thing is a misunderstanding of
evolution. The daughter species of goatsbeard in the example was not
more complex than the parent--just different.
Susan
-- ----------I am aware that the conclusions arrived at in this work will be denounced by some as highly irreligious; but he who denounces them is bound to shew why it is more irreligious to explain the origin of man as a distinct species by descent from some lower form, through the laws of variation and natural selection, than to explain the birth of the individual through the laws of ordinary reproduction.
---Charles Darwin
This archive was generated by hypermail 2b29 : Fri Oct 27 2000 - 15:41:12 EDT