Twins and Multiple Births

by

Alessandra Piontelli

• LAST REVIEWED: 28 April 2017
• LAST MODIFIED: 26 April 2018
• DOI: 10.1093/obo/9780199791231-0056

Introduction

Twin births have always been perceived as extraordinary events outside the bounds of the norm, and as such, they inevitably gave rise to many legends, myths, and peculiar theories. Opposite-sex twins feature in many creation myths, as the primeval couple that originated humankind. Same-sex (male) twins often appear as founders of towns; Romulus and Remus, the founders of Rome, are a typical example of this category. The link uniting twins is represented in Greek mythology by Castor and Pollux, who could not be separated even by death and were finally reunited in the Gemini constellation. Similar legends are to be found in mythologies all over the world. The first reference to the intrauterine activities of twins is to be found in the Bible, when Rebecca felt the children struggle within her. Until fairly recently, the eldest child of any sufficiently wealthy family generally inherited everything. Younger children were sent to swell the ranks of the convent or army. Twins created a problem. Though twins are generally born only minutes apart, one twin had to be considered younger and consequently excluded from the family legacy. Again, the biblical twins Esau and Jacob are the earliest of numerous examples. Though Esau was born first, cunningly Rebecca managed to make Jacob the heir. Besides mythology and the Bible, astrologers pondered twins for centuries, as these threatened to undermine the astrological science itself. Being born under the same astrological alignments, twins should have displayed the same disposition and destiny. However, twins were frequently unlike and met with dissimilar fates. The dilemma was never quite resolved. On the other hand, twins with their divergent fortunes served the cause of Christianity with its emphasis on free will. Twins with different destinies demonstrated that our actions could be tamed—the responsibility for our conduct was ours alone. The dispute about free will versus determinism is still at the basis of different religions. Apart from religious matters, other outlandish legends and myths were associated with twins through the centuries. Only in 1875, did Sir Francis Galton bring twins into the realm of science (Galton 1875, cited under Introductory Works). Since then science has made incredible advances. Twins have continued to raise enormous, ever-growing interest in innumerable fields.

Introductory Works

The works cited in this section are of a varied nature, ranging from anthropology to obstetrics. They are meant to give a broad view of the range of disciplines involved in twin studies. Lash 1993 provides a short study of oral and visual lore regarding twins. Lévi-Strauss 1991 looks at the Native American myth of Lynx and Coyote. Galton 1875 is the first study of twins. Sir Francis Galton argued that heredity (nature) was a stronger factor than environment (nurture) in determining the characteristics of twins. Segal 2000 explores ways in which twins enhance our knowledge of behavioral and physical development. Interest in twins was reawakened by Luigi Gedda’s work in 1951, which, translated into English, became Gedda 1961. Blickstein and Keith 2005 covers all facets of twin and multiple pregnancies.

• Blickstein, Isaac, and Louis G. Keith, eds. Multiple Pregnancy: Epidemiology, Gestation, and Perinatal Outcome. 2d ed. London: Taylor & Francis, 2005.

  DOI: 10.1201/b14615

  A landmark publication covering all facets of twin and multiple pregnancies, ranging from clinical to psychological, developmental, and practical issues. Currently available in Kindle edition.

• Galton, Francis. “The History of Twins as a Criterion of the Relative Powers of Nature and Nurture.” Journal of the Anthropological Institute of Great Britain and Ireland 5 (1875): 391–406.

  DOI: 10.2307/2840900

  The original article that brought twins into the realm of science and was a precursor in the field of behavioral genetics.

• Gedda, Luigi. Twins in History and Science. Springfield, IL: Charles C. Thomas, 1961.

  An excellent survey about twins in history and science. Published originally in 1952, the book is going to be published in 2018 as an e-book. Though somewhat outdated, this work considers every aspect of twin studies and makes fascinating reading. Luigi Gedda was the founder of gemellology, the science of twins, and the initiator of The International Society for Twin Studies.

• Lash, John. Twins and the Double. New York: Thames and Hudson, 1993.

  This short book is packed with information about the sense of awe elicited by twins in so many societies around the world, both in the past and in the present. The book is also filled with beautiful illustrations.

• Lévi-Strauss, Claude. Histoire de Lynx. Paris: Plon, 1991.

  A classic in ethnology and in myths about twins among American Indians, this book should be read by all interested in ethnographic mythology. Written in a plain and engaging style, it raises deep questions not only about twins, but also about the human condition, the future of endangered minorities, and more. A real must.

• Segal, Nancy L. Entwined Lives. New York: Plume, 2000.

  A very readable and thorough account of twin studies and behavioral genetics, shedding light on the nature versus nurture debate.