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Re: the tonight show



George,
Well, I guess we will just have to "agree to disagree" on this one. I've heard similar arguments from strict cladists, but this was the first time I've heard it from someone who recognizes the validity and usefulness of paraphyletic groups. I guess that is why I was so surprised. Of course, part of it is probably just semantics, which can make differences seem bigger than really are. C'est la vie.
------Cheers, Ken
P.S. I certainly hope that you are right about your Jurassic "dino-birds", so that Aves can be expanded someday [oooops, I think I just heard some cladists grumbling]. And wouldn't it be great if Longisquama really was related to early dino-birds, and even Feduccia and Martin had it partially right. However, I still have my doubts about Longisquama "feathers", and probably too optimistic that we could have such a happy ending to that whole debate. But stranger things have happened.
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Dinogeorge@aol.com wrote:
No, bacteria A and D simply >resemble< each other more than do bacterium A and Homo sapiens C. Homo sapiens C and bacterium D are, however, equally closely >related< to ancestral bacterium A (and thus to each other). A and D are both classified as bacteria because of their resemblance to one another, not by their phyletic separation. Here "bacteria" is a paraphyletic group, because it doesn't include its descendant taxon Homo sapiens.

I'm no fan of strictly cladistic taxonomy. I think it's quite legitimate, indeed, almost mandatory, to define some paraphyletic taxa according to resemblance and not according to phyletic relationship. I'm quite happy with a paraphyletic taxon Dinosauria from which Aves is removed (but even happier with a holophyletic taxon Aves that includes all the theropod dinosaurs, or even all the dinosaurs period).
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