Testing the bargaining vs. inclusive fitness models of suicidal behavior against the ethnographic record

Evolution and Human Behavior • Published In • Pages: 1-14 •
By Syme, Kristen L., Garfield, Zachary H., Hagen, Edward H.

Abstract

Authors examine suicidality within small-scale non-industrial societies. They use ethnographic data to test two models: deCatanzaro's inclusive fitness model and the bargaining model (suicide attempts as a costly signal of need). Limited support is found for deCatanzaro's inclusive fitness model while strong support is found for the bargaining model. Support for deCatanzaro's inclusive fitness model increased with increasing latitude; authors suggest that in climactically-harsher environments, in which elderly or infirm individuals may impose a higher burden on kin, completed suicide occurs more because it might increase inclusive fitness. Fit of and support for each model were differentially age-dependent.

Note

474 textual accounts of suicide extracted from 53 cultures in the Probability Sample Files.

Samples

Sample Used Coded Data Comment
Probability Sample Files (PSF)Researchers Ownresearchers coded suicide attempts and behaviors
Standard Cross Cultural Sample (SCCS)Other Researchers

Hypotheses (2)

HypothesisSupported
Suicidal behavior is a gambit to alter others' behavior by threatening the loss of a valuable member of the community (thereby depriving them of the victim's contributions).Supported
An individual with low reproductive potential and/or who perceives her or himself as a burden upon biological kin will be more likely to commit suicide.Supported
Documents and Hypotheses Filed By: Christina Carolus