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T.A. Curtis writes;
>You have this backwards. Evolution dictates that function follows form,
>and not the other way around. Form following function is the Lamarckian,
>not the Darwinian view.
Actually, both types of form/function interrelation may have their places in
evolution. Unusual physical adaptations (like wings or flippers) will start
simply through mutations or just plain genetic variation. Natural selection
will refine these simple, and often subtle, changes into fully functional
features (nice illiteration, huh?), that are spread throughout the breeding
population; this is the definition of speciation. In this case, simple changes
result in a profound lifestyle change: form following function.
Now, observe the trend at a transitional form, where the species has an even
mixture of primitive and derived characteristics. Natural selection will
continue to press the species toward the new lifestyle, and those animals that
have traits that best fit the new lifestyle will survive to breed the next
generation. In this case, refining the new lifestyle results in continued
physical adaptation: function following form.
Those with better experience with evolutionary theory will be able to check
where I have gone off, but I suspect I have described the process adequately.
Orphan Vertebrate Paleontologist
The most exciting phrase to hear in science, the one that heralds new
discoveries, is not "Eureka!" (I found it!) but "That's
-- Isaac Asimov