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Re: Giant birds
In a message dated 11/9/99 11:31:36 AM EST, firstname.lastname@example.org writes:
<< Something is a flightless bird when it is a) a bird (see above), b) does
fly, and c) is descendend from flying ancestors. >>
There's another definition of birds (one I particularly like because of its
simplicity): all archosaurs closer to living birds than to living
crocodilians (their closest living relatives), advocated by Peter Ax in 1989.
By this definition, all dinosaurs become birds, as do pterosaurs (if you
consider them to be ornithodiran archosaurs and not something more distant, a
la Peters, for which the evidence is beginning to accumulate). For historical
reasons, I would advocate using the term Thecodontia for the complementary
taxon, all archosaurs closer to living crocodilians than to living birds.