Cannibals avoid eating their own family
Cannibals avoid eating blood relatives. A new study by Marlies Oostland and Michael Brecht from the Humboldt-Universität zu Berlin and Princeton University, published today in Frontiers of Psychology, shows kin-avoidance in human cannibals.
The authors document vomiting and spitting out in human can-nibals, a behavior that might be triggered by internally generat-ed disgust against kin-ingestion. Cannibalistic homicide is an exceedingly rare crime in modern societies. Despite this, the researchers were able to generate a unique data set of information about 121 cannibals with approx-imately 631 victims, operating worldwide since 1900. The data set includes notorious cannibals such as Karl Denke, Jeffrey Dahmer, Andrei Chikatilo and Issei Sagawa, but also more ob-scures cases of cannibalism. They then compared the infor-mation about the cannibals with information about non-cannibalistic homicides, based on data from the FBI. The researchers found that cannibalistic homicides are a distinct category of homicides with a unique pattern of murder meth-ods, offenders, and victims. Cannibalistic offenders typically killed physically (stabbing, strangulating, beating) rather than by guns. Cannibalistic offenders were mostly older males tar-geting younger females, and their cannibalistic crimes were of-ten sex-related. Furthermore, they killed more strangers and fewer intimates than conventional offenders. Human cannibals, as other cannibalistic species, killed and ate conspecifics, occa-sionally vomited and only rarely ate kin. Interestingly, cannibal-istic offenders who killed their blood relatives had more severe mental problems than non-kin-cannibals. The authors suggest that kin-avoidance and spitting out of con-specifics might be triggered by internally generated disgust against kin-ingestion. Oostland says: “It is remarkable that even in arguably the most severe criminals of our society – cannibals, who first kill for lust and then eat for lust – we still see a biological mechanism in place to protect kin.” Brecht con-cludes: “Cannibals behave in weird ways: they kill to devour, but then they vomit. Remarkably, this is not unlike the behavior of cannibalistic fish or tadpoles, and points to anti-kin-ingestion mechanisms evolved from kin-selection many hundred millions of years ago.”
Michael Brecht Bernstein Center for Computational Neuroscience Humboldt University of Berlin, Germany firstname.lastname@example.org Phone: +49-30 2093-6770 Marlies Oostland Princeton Neuroscience Institute Princeton University, NJ, USA email@example.com Phone: +1-609-665-6590
‘Kin-avoidance in cannibalistic homicide’ Marlies Oostland & Michael Brecht
Humboldt-Universität zu Berlin │ Pressemitteilung vom 31. August 2020 │ Seite 2/2
Frontiers of Psychology (2020)
https://www.frontiersin.org/articles/10.3389/fpsyg.2020.02161 doi: 10.3389/fpsyg.2020.02161 See also: www.cannibalismresearch.org This website includes the full data set collected for this study.