Troy: The Greek Myths Reimagined (Stephen Fry's Great Mythology #3)

by Stephen Fry

Those familiar with the story of the birth of Heracles will be aware of the concept of heteropaternal superfecundation.53 Common enough in littering animals like pigs, dogs, and cats, this biological phenomenon is rare, but not unknown, in humans. There was a well-documented case in 2019.54 It is a form of what is known as polyspermy—the fertilizing of the same egg as a result of different acts of sexual congress, causing a set of twins to be born, each of whom has a different father. In the case of Leda, this crazed zygotic quirk was even more remarkable, for she gave birth to two sets of twins. Actually, that is not strictly true. It was odder even than that. When she came to term, Leda laid two eggs, each of which contained a set of twins. I know. But stay with me. From one egg came a girl and boy whom they named CLYTEMNESTRA and CASTOR, from the other a girl and boy whom they named Helen and POLYDEUCES (also known as Pollux). Tradition has it that Zeus was the father of Polydeuces and Helen, and Tyndareus of Clytemnestra and Castor. Castor and Polydeuces were brought up together as loving twin brothers, inseparably devoted each to the other.