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Re: Feduccia ORIGIN



In a message dated 97-01-10 15:47:39 EST, swf@ElSegundoCA.NCR.COM (Stan
Friesen) writes:

> I still do not have an answer to my question: what is the distribution
> of anisodactyl feet (first toe turned backwards) in dinosaurs? 

Retroverted hallux (articulating in a shallow groove on the second
metatarsal, distally on the palmar side) occurs in all theropods, and only in
theropods, at and above the common ancestor of ceratosaurians and tetanurans.
In almost all the larger cursorial forms, however, the retroverted hallux is
secondarily reduced and points, in varying degrees, posteromedially.