Re: transitional fossils

"That evolution has withstood time is
merely an indication of how powerful an explanation it really is."

How about the fact that for nearly all scientists (those who insist on solely natural mechanisms) it's the only game in town? Even if the theory were quite weak (which in several respects it is not), you'd do everything in your power to support it if you had no alternative but the supernatural, the possibility of which you as scientist cannot or will not or should not ( ? ) entertain. So there's definitely a strong bias in play. Under the circumstances, what conceivable alternative could persuade scientists to abandon it?

Don

  ----- Original Message -----
  From: Pim van Meurs<mailto:pimvanmeurs@yahoo.com>
  Cc: Keith Miller<mailto:kbmill@ksu.edu> ; asa@calvin.edu<mailto:asa@calvin.edu>
  Sent: Sunday, December 04, 2005 1:43 PM
  Subject: Re: transitional fossils

  Alexanian, Moorad wrote:

> Let us not deny the flexibility, if not total elasticity, that exists
> in the theory of evolution that can account for any new evidence that
> was originally thought as “surprising.” Witness punctuated equilibrium
> which is a modified form of the original thought.
>

  Seems that people miss the point. Evolutionary theory either
  incorporates the new data or fails to do so. Punctuated Equilibrium is
  often seen as a problem for evolutionary theory when in fact it is
  providing an explanation for the data based on existing mechanisms of
  evolution and speciation.
  PE, rather than a modified form of the original thought, basically
  extended Darwin's own views on this matter.

> Evolutionary theory is at best pure phenomenology since the “theory”
> is easily modified as new data emerge. It is quite analogous to the
> epicycle theories of planetary motions which can always be arranged to
> agree with data but would have never led to the geocentric theory of
> Copernicus.
>
  I have seen quite a few references to epicycles by creationists when
  referring to evolutionary theory. There are various problems with this.
  First of all, ID and creationism is far more comparable to epicycles
  than evolutionary theory because it at most can present ad hoc
  rationalizations to explain data.
  Evolutionary theory, rather than being 'modified', takes new data and
  incorporate it by understanding or speculating about mechanisms and
  pathways. In other words, the theory is not 'salvaged' by adding ad hoc
  explanations upon explanations but by incorporating new understandings.
  A good example would be horizontal versus vertical inheritance. In
  Darwin's time, inheritance itself was poorly understood, let alone the
  distinction between vertical and horizontal inheritance. Evolutionary
  theory however noticed that existing mechanisms of horizontal
  inheritance could help understand phylogenies better. It is estimated
  that a small percentage of variation is due to such horizontal
  inheritance. While initially the hypothesis of horizontal inheritance
  may have been seen as an ad hoc explanation, we now know that the
  mechanisms exist and have found much supporting data. Evolutionary
  theory has succesfully incorporated these findings without having to
  abandon the overal theory. Epicycles add as many exceptions as there are
  datapoints, evolutionary theory reconciles many datapoints with a single
  addition. That's a major difference.

> If evolutionary theory claims that life, consciousness and self are
> all emergent from the purely physical, then is seems to me that
> evolutionary theory can be falsified only if the Creator Himself shows
> up and tells us that it is all pure nonsense.
>
  Interesting strawman.

> A theory ought to give rise to logical implications, viz. if A, then
> B. The latter means that ~B implies ~A. It is in this sense that
> falsifiability makes sense. How can evolutionary theory be falsified?
>
>

  Good questions and long since answered by Douglas Theobald
  http://www.talkorigins.org/faqs/comdesc/phylo.html<http://www.talkoriginsorg/faqs/comdesc/phylo.html>
  29+ Evidences for Macroevolution
  Phylogenetics Primer

  Douglas presents many potential falsifiers for evolutionary as a fact
  and theory and common descent. That evolution has withstood time is
  merely an indication of how powerful an explanation it really is. Such
  is science, the more solid the theory, the harder it will be to disprove
  it, however this does not mean that it is impossible to at least in
  principle falsify evolution.

  So I find the objections raised by Cornelius and Alexanian mostly
  unconvincing as they fail to understand and appreciate what evolutionary
  theory is all about.

  An example: Evolvability, the ability for evolution itself to evolve was
  long seen as a problem for evolutionary theory. How can evolution
  explain the origin of variation. Now we realize that evolution has in
  fact guided its own variation. A good example is neutrality. Initially
  it may sound self contradicting that neutrality can be selected for,
  after all it's neutral so why should it be under control of selection.
  The answer is simple, and science for long has focused on the wrong
  questions: it's not the existing variation but the potential for
  variation (also known as variability ((the degree to which new shapes
  can be generated by mutating that sequence))) which should be considered:

  As Fontana puts it

  "The genotype-phenotype map (that is, development) induces the
  topological structure of phenotype space by determining the evolutionary
  routes along which phenotype B can be obtained from phenotype A. This is
  quite different from the traditional image of phenotype space as a
  highly regular metric space constructed around a notion of similarity
  (morphological or other) between phenotypes. Punctuated equilibria,
  constraints to variation and irreversibility in evolution become
  intelligible in this new space, its unfamiliar structure notwithstanding."

  In other words, understanding the role of tthe genotype-phenotype
  mapping has helped understanding various concepts in evolution and
  combined them under a single concept. Rather than epicycles,
  evolutionary theory actually explains by reconciling 'epicycles' under a
  common explanation.

  Fontana has written much on this topic http://www.santafe.edu/~walter/<http://www.santafe.edu/~walter/>

  Hope this helps clarify some of these issues.
Received on Mon Dec 5 03:13:47 2005