Evolutionary problems

[John Grehan]

Don McAllistar wrote

>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 how similar would be similar enough. just a rhetorical question.

>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.

Thanks for the example. There are similar instances in New Zealand where
glaciers were hypothesized to have covered the entire landscape in certain areas
and this was incongruent with the biogeogrphic patterns. The glacial models
were later modified to restrict the glacial areas.

Bill Shear  wrote

Evolutionary biologists, on the other hand, have the advantage of no
constraints save observable physical law.  They also have the luxury of
being able to constantly revise their theories to accommodate new facts; it
is not neccessary to explain those facts away or to ignore them because
they do not fit the framework.

Although this can indeed happen. But I agree, its not required.

On the other hand, no explanations are
allowed that violate known "laws of nature (themselves perhaps subject to
revision from time to time)."

If the laws of nature can be revised, then there is not necessity for
explanations
to conform I would think.

John Grehan