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Re: Climbing in theropods: extant and extinct

Nick Gardner" <ratites637@hotmail.com> wrote:

Are there special adaptions in the ankle and knee joints of parrots that permit them to be so flexible or would these have been present in theropods as well?

One thing to note is that in birds the ancestral knee (the joint between the femur and tibiotarsus) functions in hindlimb rotation, since the femur juts nearly straight forward and usually doesn't take part in locomotion. The functional knee has moved down to the tibiotarsal-tarsometatarsal joint.

Psittacine birds have zygodactyl toes, which are especially well adapted for grasping branches (among othr things). No known non-avian theropod has this feature.


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