The Returning soldier effect is a phenomenon which suggests that more boys are born during and immediately after wars. This effect is one of the many factors influencing

human sex ratio In anthropology and demography, the human sex ratio is the ratio of males to females in a population. Like most sexual species, the sex ratio in humans is close to 1:1. In humans, the natural ratio at birth between males and females is slig ...

. The phenomenon was first noticed in 1883 by

Carl Düsing Carl may refer to: *Carl, Georgia, city in USA *Carl, West Virginia, an unincorporated community * Carl (name), includes info about the name, variations of the name, and a list of people with the name *Carl², a TV series * "Carl", an episode of te ...

of the

University of Jena The University of Jena, officially the Friedrich Schiller University Jena (german: Friedrich-Schiller-Universität Jena, abbreviated FSU, shortened form ''Uni Jena''), is a public research university located in Jena, Thuringia, Germany. The un ...

, who suggested that it was a natural regulation of the status quo. Writing in 1899, an Australian physician, Arthur Davenport, used Düsing's findings to hypothesize that the cause was the difference between the comparative ill-health of the returning troops compared to the good health of their partners. Research published in 1954 by

Brian MacMahon Brian MacMahon (23 August 1923 – 5 December 2007) was a British-born American epidemiologist who chaired the Department of Epidemiology of the Harvard School of Public Health from 1958 until 1988. Best known for his work on the epidemiology o ...

and Thomas F. Pugh showed that the sex ratio of white live-births in the United States had shown a marked increase in favor of boys between 1945 and 1947, with a peak in 1946. In 2007,

Satoshi Kanazawa Satoshi Kanazawa (born 16 November 1962) is an American-born British evolutionary psychologist and writer. He is currently Reader in Management at the London School of Economics. Kanazawa's comments and research on race and intelligence, he ...

published a paper theorizing that the effect was due to "the fact that taller soldiers are more likely to survive battle and that taller parents are more likely to have sons". This was based on his research of British Army records from the First World War, which showed that "surviving soldiers were on average more than one inch (3.33 cm) taller than fallen soldiers". Valerie Grant attributed it to changing hormone levels of women during war, as they tended to "adopt more dominant roles". William H. James writing in 2008 gave an increase in coital rates by returning soldiers as a possible cause. He also noted that a fall in the ratio of male births had been recorded in Iran following the

Iran–Iraq War The Iran–Iraq War was an armed conflict between Iran and Iraq that lasted from September 1980 to August 1988. It began with the Iraqi invasion of Iran and lasted for almost eight years, until the acceptance of United Nations Security Counci ...

, "explained by psychological stress causing pregnant women disproportionately to abort male fetuses".

References

Aftermath of war Military psychiatry Military medicine Human sex ratio {{Mil-stub

See also

References