Re: re-whales from rodents

Arthur V. Chadwick (
Sat, 21 Aug 1999 17:45:44 -0700

At 09:44 AM 08/21/1999 -0700, I wrote:
>Johnson says "Nobody is proposing that an ancestral rodent (or whatever)
>became a whale or a bat in a single episode of speciation...." Please.
>Johnson is a lawyer! Does he know the difference between a whale and a
>rodent? Do you really expect him to? I think the emphasis ought (and quite
>properly so) to be on the point he is attempting to make, and not on the
>specific details of the paleontology. Lets argue about the point he is
>making, and not about whether he did or did not grab the correct ancestor.
>That borders on ad hominem argumentation. Now if he were a vertebrate
>paleontologist, then we could (if we had the facts straight ourselves),
>take him to task if he had made a mistake.

Where did Johnson get his impression? Perhaps from reading Stanley:

"Let us suppose that we wish, hypothetically, to form a bat or a whale...
[by a]
process of gradual transformation of established species. If an average
chronospecies lasts nearly a million years, or even longer, and we have at
our disposal only ten million years, then we have only ten or fifteen
chronospecies to align, end to end, to form a continuous lineage
our primitive little mammal with a bat or a whale. This is clearly
preposterous... A chain of ten or fifteen of these might move us from one
small rodent like form to a slightly different one, perhaps representing a
new genus, but not to a bat or a whale! "