I saw an ad in an NYC rag. I did the one you see, but I did a 2nd one, too. And so I did. So I've had this running disagreement with t.n.
All mammals have a backbone.
All mammals have four limbs. All mammals breath air. All mammals are warm-blooded. All mammals produce milk for their young. A bit of more info here on the suitability of men to breastfeed.