Superfecundation
Encyclopedia
Superfecundation is the fertilization of two or more ova
from the same cycle
by sperm
from separate acts of sexual intercourse
. The term superfecundation is derived from fecund
, meaning the ability to produce offspring.
Heteropaternal superfecundation occurs when two different males father fraternal twins. When the parents of fraternal twins are involved in a paternity
suit, the odds are about 1 in 40 that the children are actually half-siblings.
In common usage, the term superfecundation is often used instead of heteropaternal superfecundation. The terms are practically equivalent because, though it is speculated that superfecundation by the same father is a common occurrence, it can only be proven to have occurred when there are multiple fathers.
is usually suspended during pregnancy
to prevent further ova becoming fertilized and to help increase the chances of a full term pregnancy. However, if an ovum is released after the female was already impregnated when previously ovulating, there is a chance of a second pregnancy—albeit at a different stage of development. This is known as superfetation
.
s and dog
s. Stray dogs often produce litters in which every puppy has a different father.
Though rare in humans, many cases have been documented. In 1810, American physician John Archer documented a case in which a white woman gave birth to mixed twins
—one white, one mixed-race—after having sex with a black man and a white man within a short time. In 1994 a woman gave birth to twin girls named Skylar and Ariana who have different fathers. In June 2008, a Texas woman gave birth to fraternal twins fathered by different men. In that case, a DNA test concluded that there was a 99.999 percent chance that the twins had different fathers. The twins' mother acknowledged having had intercourse with more than one man in a short period of time close to the conception date.
, Heracles
and his twin Iphicles
are examples of heteropaternal superfecundation, with Heracles fathered by the god Zeus
and Iphicles by a mortal man Amphitryon.
In another Greek myth, Leda
conceives four children (Helen of Troy, Clytemnestra
, and Castor and Pollux
) in the same night by two different men. Two are children of Zeus, who comes to Leda disguised as a swan, and two are the children of Leda's mortal husband, Tyndareus
. Which men father which children varies widely among accounts, in some cases establishing that the Gemini twins Castor and Pollux are born of different fathers. The heteropaternal superfecundation involved in this myth is especially unusual, because instead of giving birth to the children, Leda lays eggs that hatch them.
soap opera
Days of our Lives
, a character named Sami Brady
has fraternal twins born of two different fathers after having sex with both men within hours of each other. Similarly, the character Blake Marler
on CBS
's Guiding Light
initially believes her twins have different fathers, but they are later proven to both be her husband's biological children. On One Life to Live
in 2001, longtime heroine Victoria Lord Davidson discovers her twin daughters have different fathers. On "American Horror Story
", Vivianne is pregnant with the babies of her husband and a ghost, Tate, that lives in the house, whom she was raped by.
Ovum
An ovum is a haploid female reproductive cell or gamete. Both animals and embryophytes have ova. The term ovule is used for the young ovum of an animal, as well as the plant structure that carries the female gametophyte and egg cell and develops into a seed after fertilization...
from the same cycle
Menstrual cycle
The menstrual cycle is the scientific term for the physiological changes that can occur in fertile women for the purpose of sexual reproduction. This article focuses on the human menstrual cycle....
by sperm
Spermatozoon
A spermatozoon is a motile sperm cell, or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote...
from separate acts of sexual intercourse
Sexual intercourse
Sexual intercourse, also known as copulation or coitus, commonly refers to the act in which a male's penis enters a female's vagina for the purposes of sexual pleasure or reproduction. The entities may be of opposite sexes, or they may be hermaphroditic, as is the case with snails...
. The term superfecundation is derived from fecund
Fecundity
Fecundity, derived from the word fecund, generally refers to the ability to reproduce. In demography, fecundity is the potential reproductive capacity of an individual or population. In biology, the definition is more equivalent to fertility, or the actual reproductive rate of an organism or...
, meaning the ability to produce offspring.
Heteropaternal superfecundation occurs when two different males father fraternal twins. When the parents of fraternal twins are involved in a paternity
Paternity (law)
In law, paternity is the legal acknowledgment of the parental relationship between a man and a child usually based on several factors.At common law, a child born to the wife during a marriage is the husband's child under the "presumption of legitimacy", and the husband is assigned complete rights,...
suit, the odds are about 1 in 40 that the children are actually half-siblings.
In common usage, the term superfecundation is often used instead of heteropaternal superfecundation. The terms are practically equivalent because, though it is speculated that superfecundation by the same father is a common occurrence, it can only be proven to have occurred when there are multiple fathers.
Conception
Superfecundation most commonly happens within hours or days of the first instance of fertilization with ova released during the same cycle. There is a small time window when eggs are able to be fertilized. Sperm cells can live inside a female’s body for 4–5 days. Once ovulation occurs, the egg remains viable for 12–48 hours before it begins to disintegrate. Thus, the fertile period can span 5–7 days. OvulationOvulation
Ovulation is the process in a female's menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum . Ovulation also occurs in the estrous cycle of other female mammals, which differs in many fundamental ways from the menstrual cycle...
is usually suspended during pregnancy
Pregnancy
Pregnancy refers to the fertilization and development of one or more offspring, known as a fetus or embryo, in a woman's uterus. In a pregnancy, there can be multiple gestations, as in the case of twins or triplets...
to prevent further ova becoming fertilized and to help increase the chances of a full term pregnancy. However, if an ovum is released after the female was already impregnated when previously ovulating, there is a chance of a second pregnancy—albeit at a different stage of development. This is known as superfetation
Superfetation
Superfetation is the simultaneous occurrence of more than one stage of developing embryo in the same animal. In mammals it manifests as the formation of a fetus from a different menstrual cycle while another embryo is already present in the uterus...
.
Heteropaternal superfecundation
Heteropaternal superfecundation is common in animals such as catCat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s and dog
Dog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s. Stray dogs often produce litters in which every puppy has a different father.
Though rare in humans, many cases have been documented. In 1810, American physician John Archer documented a case in which a white woman gave birth to mixed twins
Mixed twins
Mixed twins are fraternal twins born to multiracial families which differ in skin color and other traits considered to be racial features.From a biological point of view, the differences in these fraternal or dizygotic twins from two biracial parents are not surprising. In humans, a relatively...
—one white, one mixed-race—after having sex with a black man and a white man within a short time. In 1994 a woman gave birth to twin girls named Skylar and Ariana who have different fathers. In June 2008, a Texas woman gave birth to fraternal twins fathered by different men. In that case, a DNA test concluded that there was a 99.999 percent chance that the twins had different fathers. The twins' mother acknowledged having had intercourse with more than one man in a short period of time close to the conception date.
Use in mythology
In Greek mythologyGreek mythology
Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
, Heracles
Heracles
Heracles ,born Alcaeus or Alcides , was a divine hero in Greek mythology, the son of Zeus and Alcmene, foster son of Amphitryon and great-grandson of Perseus...
and his twin Iphicles
Iphicles
In Greek mythology, Iphicles is the name of three different people:*The half-brother of Heracles, being the son of Alcmene and her human husband Amphitryon, whereas Heracles was her son by Zeus. Iphicles was the father of Heracles' charioteer Iolaus by Automedusa, daughter of Alcathous...
are examples of heteropaternal superfecundation, with Heracles fathered by the god Zeus
Zeus
In the ancient Greek religion, Zeus was the "Father of Gods and men" who ruled the Olympians of Mount Olympus as a father ruled the family. He was the god of sky and thunder in Greek mythology. His Roman counterpart is Jupiter and his Etruscan counterpart is Tinia.Zeus was the child of Cronus...
and Iphicles by a mortal man Amphitryon.
In another Greek myth, Leda
Leda (mythology)
In Greek mythology, Leda was daughter of the Aetolian king Thestius, and wife of the king Tyndareus , of Sparta. Her myth gave rise to the popular motif in Renaissance and later art of Leda and the Swan...
conceives four children (Helen of Troy, Clytemnestra
Clytemnestra
Clytemnestra or Clytaemnestra , in ancient Greek legend, was the wife of Agamemnon, king of the Ancient Greek kingdom of Mycenae or Argos. In the Oresteia by Aeschylus, she was a femme fatale who murdered her husband, Agamemnon – said by Euripides to be her second husband – and the Trojan princess...
, and Castor and Pollux
Castor and Pollux
In Greek and Roman mythology, Castor and Pollux or Polydeuces were twin brothers, together known as the Dioscuri . Their mother was Leda, but Castor was the mortal son of Tyndareus, king of Sparta, and Pollux the divine son of Zeus, who visited Leda in the guise of a swan...
) in the same night by two different men. Two are children of Zeus, who comes to Leda disguised as a swan, and two are the children of Leda's mortal husband, Tyndareus
Tyndareus
In Greek mythology, Tyndareus or Tyndareos was a Spartan king, son of Oebalus and Gorgophone , husband of Leda and father of Helen, Castor and Polydeuces, Clytemnestra, Timandra, Phoebe and Philonoe.Tyndareus had a brother named Hippocoon , who seized power and exiled Tyndareus...
. Which men father which children varies widely among accounts, in some cases establishing that the Gemini twins Castor and Pollux are born of different fathers. The heteropaternal superfecundation involved in this myth is especially unusual, because instead of giving birth to the children, Leda lays eggs that hatch them.
Literature
- In John SteinbeckJohn SteinbeckJohn Ernst Steinbeck, Jr. was an American writer. He is widely known for the Pulitzer Prize-winning novel The Grapes of Wrath and East of Eden and the novella Of Mice and Men...
's novel East of Eden, the twin brothers Caleb and Aaron may have different fathers. - In Bryce CourtenayBryce CourtenayArthur Bryce Courtenay AM is a South-African-born naturalized Australian novelist and one of Australia's most commercially successful authors.-Background and early years:...
's "Australian" Trilogy, twin brothers Tommo and Hawk Solomon have different fathers, and were conceived on the same day. - In Kotomi Aoi's "Boku wa Imōto ni Koi wo Suru - Secret SweetheartsBoku wa Imoto ni Koi o Suruis manga series by Kotomi Aoki. Originally serialized in Shōjo Comic, the individual chapters were published in ten tankōbon volumes by Shogakukan from May 2003 until August 2005...
", the twins Yori and Iku are fathered by different men. - In Zadie SmithZadie SmithZadie Smith is a British novelist. To date she has written three novels. In 2003, she was included on Granta's list of 20 best young authors...
's novel White TeethWhite TeethWhite Teeth is a 2000 novel by the British author Zadie Smith. It focuses on the later lives of two wartime friends—the Bangladeshi Samad Iqbal and the Englishman Archie Jones, and their families in London...
, Irie becomes pregnant with twins after having sex on the same day with brothers Millat and Magid, themselves identical twins, thus making it impossible to establish paternity.
Television
On the NBCNBC
The National Broadcasting Company is an American commercial broadcasting television network and former radio network headquartered in the GE Building in New York City's Rockefeller Center with additional major offices near Los Angeles and in Chicago...
soap opera
Soap opera
A soap opera, sometimes called "soap" for short, is an ongoing, episodic work of dramatic fiction presented in serial format on radio or as television programming. The name soap opera stems from the original dramatic serials broadcast on radio that had soap manufacturers, such as Procter & Gamble,...
Days of our Lives
Days of our Lives
Days of our Lives is a long running daytime soap opera broadcast on the NBC television network. It is one of the longest-running scripted television programs in the world, airing nearly every weekday in the United States since November 8, 1965. It has since been syndicated to many countries around...
, a character named Sami Brady
Sami Brady
Samantha Gene "Sami" Hernandez is a fictional character on the NBC soap opera Days of our Lives. She was born onscreen on October 16, 1984, though was later SORASed to October 16, 1977. Created by head writer Margaret DePriest, Sami has been portrayed by Alison Sweeney since January 22, 1993...
has fraternal twins born of two different fathers after having sex with both men within hours of each other. Similarly, the character Blake Marler
Blake Marler
Christina Blake Marler is a fictional character on CBS's daytime drama Guiding Light. She was portrayed by Elizabeth Keifer from August 19, 1992 to September 18, 2009...
on CBS
CBS
CBS Broadcasting Inc. is a major US commercial broadcasting television network, which started as a radio network. The name is derived from the initials of the network's former name, Columbia Broadcasting System. The network is sometimes referred to as the "Eye Network" in reference to the shape of...
's Guiding Light
Guiding Light
Guiding Light is an American daytime television drama that is credited by the Guinness Book of World Records as the longest running drama in television and radio history, running from 1937 until 2009...
initially believes her twins have different fathers, but they are later proven to both be her husband's biological children. On One Life to Live
One Life to Live
One Life to Live is an American soap opera which debuted on July 15, 1968 and has been broadcast on the ABC television network. Created by Agnes Nixon, the series was the first daytime drama to primarily feature racially and socioeconomically diverse characters and consistently emphasize social...
in 2001, longtime heroine Victoria Lord Davidson discovers her twin daughters have different fathers. On "American Horror Story
American Horror Story
American Horror Story is a horror-drama television series created and produced by Ryan Murphy and Brad Falchuk. The series centers on the Harmon family: Ben, Vivien and their daughter Violet, who move from Boston to Los Angeles after Vivien has a miscarriage and Ben has an affair...
", Vivianne is pregnant with the babies of her husband and a ghost, Tate, that lives in the house, whom she was raped by.
External links
- "Is it possible for fraternal twins to have different fathers?" at The Straight DopeCecil AdamsCecil Adams is a name, possibly a pseudonym, designating the American author of The Straight Dope, a popular question and answer column published in The Chicago Reader since 1973. Ed Zotti is Adams' current editor....
- Lu et al. (1994). "Paternity Identification in Twins with Different Fathers". Journal of Forensic Science July; 39(4), 1100-2.
- Gawker (May 18, 2009)
- Doctors Discover Dallas Twins Have Two Different Dads. http://www.foxnews.com/story/0,2933,520524,00.html