As I was driving home one day, it occurred to me that suicide might be adaptive. I was surprised to find that this has been investigated and the answer is "yes, suicide can be adaptive". Notice that I say, "can be" rather than "is". Being an evolutionary dead end is extreme. It is a bad idea all-round. Two related things appear to motivate suicide in terms of inclusive fitness: 1) Ideation that reproductive success is negligibly probable. 2) Ideation that one's continued existence is a burden on kin and negatively impacts their reproductive fitness. The first can come from isolation, few friends, and no partner. Likely depression is both cause and effect. The second is about resources and the impact of the individual on those resources. As above, a link to depression is likely. People feel ‘useless’ to kin, that they are just taking up space, and they are, or will come to be, a burden to kin. In genetically related groups, self-removal may increase ov...