PE and mechanisms

Wesley R. Elsberry (
Fri, 5 Mar 1999 11:52:31 -0600 (CST)

Neal Roys writes:


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

Actually, the original 1972 essay by Eldredge and Gould quite
clearly identifies the prevalence of allopatric speciation of
peripheral isolates as the mechanism by which the pattern
of PE arises.

I think that my FAQ on PE covers this in sufficient detail.
See <>.

NR>So without a testable mechanism, PE, and the
NR>macro-evolution it implies, does not qualify as science.
NR>Give me a testable mechanism by which the PE pattern
NR>occurred (please include the falsification scenario) and
NR>then we can agree that macro-evolution is part of science.

Allopatric speciation of peripheral isolates is generally held
among biologists to be the most common mode of speciation.
Falsifying this is easy to specify, but hard to do: Show that
some *other* mode of speciation is actually more common.
Given that even the existence of sympatric speciation was held
in doubt by many until relatively recently, I think that it
will not become the case that biologists switch modes of

I'm afraid that I don't follow the jump from finding PE to be
a real theory and accepting macro-evolution as a real
phenomenon. I suggest having a look at