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Definition of Clade (was Re: Kileskus and Proceratosauridae)
The term "clade," when first erected, was defined _explicitly_ to apply _only_
to monophyletic groups (Huxley, 1958, p. 27). Hence, there is no such thing as
a "paraphyletic clade" or a "polyphyletic clade." There are certainly
paraphyletic or polyphyletic _groups_, but they are not clades.
Huxley, J.H. 1958. Evolutionary processes and taxonomy with special reference
to grades. Uppsala Universitets Arksskrift 1958:21-39.
Jerry D. Harris
Director of Paleontology
Dixie State College
225 South 700 East
St. George, UT 84770 USA
Phone: (435) 652-7758
Fax: (435) 656-4022
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