Nipples are due to the different development path of the sexes during the development of the fetus. Male and females have corresponding genitalia. Penis- clitoris, foreskin-labia, testes-ovaries, urethra modified for fertilization of the eggs, etc. Incomplete development of a specific sex or chromosomes of one sex and genitalia over the other does happen. It's like sex is determined by the chromosomes but the development of the correct sex organs depends on hormonal balance in the pregnancy.
The "thang" between the legs and where to put it does seem to
work out fairly well when considering the total earth population.
Many with the limp dick also have a legbag but it's hard to miss the thunderbucket.
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"...only the shadow knows"
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