Ask A Scientist© Biology Archive

 
Question:  How is it possible for people to be born hermaphrodites?
Pat J Bushong
 
Answer:  Because the sexual organs derive from common precursors, these precursors 
can develop into a combination of male and female organs, or, often, into the male 
organ on one side of the body and the female on the other with the external genitals 
being a hybrid of the two.  This condition is rare, with only 302 reported cases 
between 1899 (the first medical report) and 1974.  All of this is caused by a hormonal 
failure in the fetus, not by the XX or XY genotype.  The word hermaphrodite, by the 
way, comes from the two Greek gods Hermes (male) and Aphrodite (female).  You could 
find out more in a textbook on human development: look in the section on development 
of the urogenital system.  This information comes from Animal Development, by Hopper 
& Hart, 2nd ed.  --ProfBill