Also in this week's column:

• What are zombie behaviours?
• Is it possible to swallow while standing on your head?
• What is the use of the hymen?

Asked by Nick Pettefair of Swindon, United Kingdom

On average, human females are smaller in stature, have smaller bones, smaller skulls, and have smaller joints than human males.

Women have narrower shoulders, (but wider pelvises) and tinier elbows, wrists, hands, ankles, and knees (giving women a greater tendency to be knock-kneed). If this were not enough, women also have smaller brains, hearts, lungs, kidneys, and less muscle mass (but a higher percentage of body fat). Women’s legs constitute only 51 per cent of their overall height compared with 56 per cent for men.

Consistent with all of the above, women’s feet are smaller than men’s. Given the other anatomical gender differences, it would be surprising if it were otherwise.

The human skeleton is balanced for maximum efficiency. It takes something major to alter the body’s engineering needs. The weight from breasts, even very large breasts, is not nearly enough of a factor. All other things being equal, a woman with very large breasts is no more likely to have a problem keeping her balance than a woman of identical height with very small breasts and with identical sized feet.

And the old saying, "women’s feet are smaller to let them stand closer to the kitchen sink", just doesn’t measure up either.

Stephen Juan, Ph.D. is an anthropologist at the University of Sydney. Email your Odd Body questions to s.juan@edfac.usyd.edu.au

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