Evolutionary methods

[Don McAllister]

John Grehan wrote: I have been interested to read the various comments

> that have been generated. I was particularly interested in the reference
> to bird "milk" in repsonse to a previous posting. I think that illustrates
> the problematic nature of attempting to provide demarkation criteria
> for the acceptance or rejection of a theory.

Bird (=pigeon) milk might have been considered to have falsified evolution if its
chemical makeup and/or manner of generation was similar to that of mammals. But

>
> The evolutionary method I use involves a biogeographic method
> where distributions are mapped as line graphs. These graphs can be
> spatially correlated with earth-process features such as transform
> faults, spreading ridges etc. These correlations have led in the past to
> predictions about geological structures unknown to geologists at the time.
> These predictions were later corroborated empirically by the geologist.
> An example is the tectonic structure of the Americas were western rocks are
> not homologous with those to the east. This was predicted on the basis of
> distribution patterns in the 1950's and early 1960's and was totally
> unknown to geologists at the time.

I think this is a particulary strong type of prediction, the less likely the
instance, the stronger a test of the theory.  Of course there are other
biogeographic examples. Biologists argued from their data that the Queen Charlotte
Islands (Haida Gwaii), were unglaciated during the Wisconsin, a hypothesis rejected
by geologists. Later geologists found radioactive carbon data refuting their own
hypothesis.

don
Don McAllister