Use of the term was common until the mid-to-late twentieth century, when anthropology effectively deconstructed and revised many of the concepts and categories around the study of kinship and social ties.
The bonds allowing for chosen kinship may include religious rituals, close friendship ties,[3] or other essential reciprocal social or economic relationships.
[5]: 31–32 The idea of fictive kin has been used to analyze aging,[6] foreign fighters,[7] immigrant communities,[3] and minorities[8][9] in modern societies.
Recently, many anthropologists have abandoned a distinction between "real" and "fictive" kin, because many cultures do not base their notion of kinship on genealogical relations.
[21] Carsten argued that relatedness should be described in terms of indigenous statements and practices, some of which fall outside what anthropologists have conventionally understood as kinship.
[22] This does not imply, however, that human non-kin relationships, such as in tit-for-tat situations, even within a friendship relation, are more important than kin relationships, since their motivation is also related to one's survival and perpetuation, or that people are necessarily bound to the culture they are inserted in, nor can it be generalized to the point of claiming all individuals always undervalue kinship in the absence of nurturing.
Herbert Gintis, in his review of the book Sex at Dawn, critiques the idea that human males were unconcerned with parentage, "which would make us unlike any other species I can think of".
This coefficient of relationship is an important component of the theory of inclusive fitness, a treatment of the evolutionary selective pressures on the emergence of certain forms of social behavior.
It may be, for instance, that in respect of a certain social action performed towards neighbours indiscriminately, an individual is only just breaking even in terms of inclusive fitness.
In fact, the individual may not need to perform any discrimination so sophisticated as we suggest here; a difference in the generosity of his behaviour according to whether the situations evoking it were encountered near to, or far from, his own home might occasion an advantage of a similar kind.