Re: Peppered Moths - in black and white (part 2 of 2)

Kevin O'Brien (
Thu, 1 Apr 1999 17:03:33 -0700

>Kevin O'Brien wrote:
>>>Evolution is something beyond this. Evolution is
>>>irreversible; the moth phenomenon is reversible; therefore, the
>>>phenomenon is not an instance of evolution. I don't think I'm making
>>>idiosyncratic definitions here.
>>As a matter of fact you are, but it is understandable. You have accepted
>>true the creationist claim that "macroevolution" is the only true form of
>>evolution. Since "macroevolution" does involve more or less irreversible
>>change, it is natural for you to assume that evolution as a whole requires
>>irreversible change. However, "microevolution" is also evolution, even
>>though changes here are not always irreversible.
>Irreversibility has long been recognized as a general characteristic of
>evolution, micro and macro. Dollo's Law, isn't it?

Admittedly I am not familiar with that, but my understanding of evolution,
based on reading the books by Futuyma and others, suggests that this is not

>But I can see that my belief in macroevolution influences me in this. If I
>were wedded to microevolution, then the slight variations I see among
>populations would seem to me the very stuff of evolution, as it did for

It is not a matter of being wedded to anything; "microevolution" is
legitimate evolution, as Darwin established and subsequent research has
continuously demonstrated.

>BTW, I don't think macro is the "only true form of evolution." And I don't
>think creationists believe in macroevolution; they believe in special

True, but by restricting any discussion of evolution in general to
"macroevolution" they hope to eliminate the clear evidence based on
"microevolution" that evolution is a real phenomenon and instead force all
debate into an arena where they think there is no evidence to support

Kevin L. O'Brien