15. The Tocci Twins Were Dicephalus
Conjoined twins are usually classified regarding where they are joined. Chang and Eng Bunker, the “original” Siamese twins were joined at the chest and had separate organs, except for a liver that was fused between them. Some are joined at the brain and meninges so that they effectively share one head; others are joined at the hip or pelvis. Most frequently, conjoined twins share a common abdomen and may have only one heart, liver, and intestine. Doctors believe that the condition results when a fertilized egg separates to produce twins but fails to separate.
Today, many conjoined twins can be successfully separated, while others go on to live productive, independent lives. However, separation was not an option for the Tocci brothers, who lived before medicine had developed to that point. Giacomo and Giovanni Tocci were dicephalus, meaning that they had separate heads. They were joined at the sixth rib and had their own hearts and other organs. They also each had their own set of two arms, which were fully functional. However, they had only one leg each and only one set of genitalia. If they had been born in the twentieth century, they probably could have been successfully separated.