Re: Emus a Model for Dinosaurs?

[Tim Williams <twilliams_alpha@hotmail.com>]

Michael Skrepnick wrote:

> So if the center of locomotion shifts in neornithes forward from acetabulum 
> to the knee, as a compensatory shift in the center of mass / gravity (due 
> primarily to a reduction in the caudal series ), can we assume Caudipteryx 
> grade animals also may have moved via a knee driven mechanism?

No, we cannot assume this.

See:

Christiansen, P. and Bonde, N. (2002).  Limb proportions and avian 
terrestrial locomotion. J. Ornithol. 143: 356-371.

Mentioned here:

http://dml.cmnh.org/2003Sep/msg00338.html

Among other things, Christiansen and Bonde argue that _Caudipteryx_ did 
*not* have avian-style stride generation, contradicting the assertion of 
Jones et al. (2002) that _Caudipteryx_ did (and was therefore a secondarily 
flightless bird).

Jones, T.D., Farlow, J.O., Ruben,  J.A., Henderson, D.M. and Hillenius, W.J. 
(2000).  Cursoriality in bipedal archosaurs.  Nature 406: 716-718.

Discussed here:

http://dml.cmnh.org/2000Aug/msg00303.html

Cheers

Tim

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