Reply #24: Gould &c. [View All]

[Ediacara]

I didn't mean to imply Gould thought that evolutionary history was unknowable (although I can certainly see how it could be read that way). My beef with Gould is that he uses differences and weirdness (disparity) to artificially inflate what happened during the Cambrian. Any minor weird character is taken to be indicative of a new phylum. I think this is silly.

It may just exemplify the differences between phylogenetic and linnean frames of mind. Phylogenetic thinking argues that derived similarities are more important than derived differences, but linnean thinking groups organisms based on derived AND primitive similarities, and makes a big deal out of oddities.

If you want a good read concerning genetic clocks, the Cambrian explosion, and fossil animals around before the Cambrian, check out the last chapter in:

Levinton, J. S. 2001. Genetics, Paleontology, and Macroevolution (2nd Edition). Cambridge University Press, Cambridge. 617 Pp.

As for the rest of the book..... it's uh... about 450 pages of very, very, very dry stuff concerning mostly genetics that could easily have been cut down to 250 pages. The last chapter though, on the Cambrian explosion, can be read without really having read the rest of the book and is very insightful and informative. This is where the concept of the "evolutionary lawn" comes up.