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Re: DIGIT LOSS INQUIRY



In a message dated 8/15/01 7:50:32 AM EST, christopher-brochu@uiowa.edu 
writes:

<< Isn't this circular?  Phylogenetics shows us that all transitions in digit 
count are losses, not gains.  Therefore, digit loss should be upweighted in 
phylogenetics. >>

This hasn't bothered taxonomists in the past. E.g., it was once found that 
dinosaurs had perforate acetabula and that "thecodontians" had imperforate 
acetabula. So, suddenly, any non-pterosaurian archosaur with a perforate 
acetabulum was a dinosaur, and any non-pterosaurian archosaur with an 
imperforate acetabulum was a "thecodontian."