Re: Def'n of Science

Tim Ikeda (
Tue, 02 Mar 1999 23:32:47 -0500

Hello Neal, you wrote...

>>>[NR] Marxism and Freudianism, which came out about the same time as
>>>Darwinism,were originally thought to be sciences. But when it was
>>>realized that they weren't testable, they were relegated to the realm
>>>of philosophy.

Brian Harper replied:
>>[BH] But Darwinism was not. Really, what's your point?
> My point is that since the discovery of
> 1)the pattern of punctuated equilibrium
> and
> 2)several biological examples of irreducible complexity, including
> that of the bacteria's flagellum, which requires 50 proteins to
> form it's rotary motor--any fewer and you have a broken flagellum,
> not a reduced function flagellum
> the conditions of Darwin's falsification scenario have been met.
> Therefore *gradual* Darwinian macro-evolution should also be
> taught only in philosophy classes along with Marxism.

[Aside: PE and phyletic gradualism are not mutually exclusive...]

Hmmm. Observation #1 does not appear to imply any falsification
of Darwin's scenario. For example, that some organisms evolved via
a PE-like manner does not imply that *no intermediates* should be
found, only that such examples should be relatively rare. Again,
that's "rare", not non-existent.

Observation #2, irreducible complexity, is interesting but generally
not seen as a falsification of evolution (An aside: Even if some
"extranatural" agent did tinker with the early organisms on earth,
this does not rule out the possibility of subsequent "macro-evolution").

The fact is, irreducibly complex systems certainly can evolve, and
many of the parts found in the irreducibly complex systems cited by
your source show structural and sequence similarities to components
found elsewhere in the cell which perform different functions (FWIW,
If you investigate further, you'll find your source did not spend
much time discussing these particular observations). So in many cases,
there is evidence of ancestry even in irreducibly complex systems.
Whether the bacterial flagellum could have evolved remains an open,
& not shut question.

[...Brian Harper's comments deleted...]

> Punctuated Equilibrium *is* a pattern. But to date there is not
> even one proposal for a testable mechanism that could have caused
> the PE pattern.

Personally, I'm very skeptical about that claim. Perhaps you mean
something other than the "Punctuated Equilibria" which evolutionary
biologists talk about.

> So without a testable mechanism, PE, and the macro-evolution it
> implies, does not qualify as science.

Be careful about using the term, "puncuated evolution". I do not
think it implies the "macro-evolutionary", high levels of change
which I think you are trying to address.

> Give me a testable mechanism
> by which the PE pattern occurred (please include the falsification
> scenario) and then we can agree that macro-evolution is part of
> science.

Peripatric speciation?
See: by Wesley Elsberry.

Again, I worry that discussions about PE are not necessarily relevant
to the questions you seem to have about "macro-evolution". For example,
let us propose that species-A shares a much more recent common ancestor
with species-B than with species-C. How might we test this macro-
evolutionary proposition? We could compare DNA or protein sequences.
We could examine the fossil record for the relative position and
timing of species emergence in the record. We could examine the
behavoir and ecological niches in which the species are found. In
short there can be many ways to examine "macro-evolutionary"
propositions which have little to do with the mechanisms of PE.

Tim Ikeda (despam address before use)

"Evolutionary theory seems so simple almost anyone can misunderstand it"
- David Hull