Is there any link between suicide among humans and the self-sacrificial behaviours of eusocial species like some insects? This is what researchers of a new study have attempted to find out. The paper is published in Psychological Review. Species living in colonies like the shrimp, mole rat, honeybees and ants, are known to sometimes self-sacrifice themselves. Perhaps, human suicide has evolutionary roots in this behaviour?
A team led by a suicide expert from the Florida State University, Thomas Joiner, analysed scientific knowledge with the aim of drawing parallels between the two in case there is an equivalent of suicide in humans among animals.
They started off with the hypothesis that humans display characteristics of eusocial species like ensuring survival through division of labour and multigenerational care of the young. Joiner says that since humans are eusocial too, they might be having other related features such as self-sacrifice behaviours.
This type of eusocial behaviour involves an individual giving himself (and his genes) up but also saving some copies of his genes in his relatives for the greater good in terms of evolution, resulting in a net benefit “on the gene level”. This behaviour is, therefore deemed adaptive. However, when human suicide was analysed, it was found to deviate from this general rule: rather, the researchers say it is “highly maladaptive and very psychopathological”.
The question that remains to be answered is whether modern human suicide is a maladaptive form of the adaptive behaviour that is self-sacrifice in eusocial species.
Finding animal models to relate to the human version is hoped to help understand how it works at the brain level. Prevention measures can be developed from this knowledge, which is why researchers are working on this.