Re: Testing in historical science
David Campbell (bivalve@mailserv0.isis.unc.edu)
Thu, 4 Dec 1997 01:08:08 -0400>Of course, the experiments in experimental science are totally controlled.
>Such is not the case in historical science. I am not sure about your comment
>about historical geology. It seems to me that much of it is like cosmology
>rather than astrophysics. I must say I do not understand the term
>"evolutionary changes." It seems to be all-encompassing. You are not
>certainly talking about BIG changes, are you?
How big is BIG? Nothing in lab has yet been considered a new family, as
far as I know, but advances in molecular embryology may soon let us grow a
fish with legs or other rather distictive creatures.
Some examples of what I mean about historical geology may help. A
sample of sediment can be put under heat and pressure, and the resulting
rock be compared with natural rocks to see if they encountered similar
levels of heat and pressure. Modern echinoderms cannot survive except in
seawater of fairly normal salinity-it's pretty basic to their physiology.
Fossil echinoderms can then be assumed to have lived in marine water,
especially since the associated fauna, rock types, etc. are also marine in
their modern occurrence.
David Campbell