Dear all,

I'm glad to see that the feedback to these quizes remains encouraging,
so I'll keep going until you beg me to stop!

This week's question is another Aristotelian one, and also from his "On
the Gait of Animals". I will give to you straight (via Farquharson's

"why do man and bird, though both bipeds, have an opposite curvature of
the legs. For man bends his legs convexly, a bird has his bent

Now, before an early bird chirps up, I will note immediately that the
joint in question is the knee in man but the ankle in birds. However, I
don't think that this fact alone answers the question ... does it?

I look forward to your musings.


Dr. Chris Kirtley MD PhD
Associate Professor
HomeCare Technologies for the 21st Century (Whitaker Foundation)
NIDRR Rehabilitation Engineering Research Center on TeleRehabilitation
Dept. of Biomedical Engineering, Pangborn 105B
Catholic University of America
620 Michigan Ave NE
Washington, DC 20064
Tel. 202-319-6247, fax 202-319-4287

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