Intergroup communication concerns the verbal and nonverbal interaction between individuals from different groups. Since about the 1980s, the social identity perspective (including social identity, self-categorization, ethnolinguistic vitality, and communication accommodation theories) has provided much impetus to research on intergroup communication. One way to advance intergroup communication research, then, is to expand the social identity perspective. Evolutionary psychology, a research program firmly rooted in natural selection theory and its modern synthesis, can help achieve this goal. For example, a functional analysis of language acquisition suggests—and research confirms—that language (similar to sex and age but not race) is a dedicated dimension of social categorization. This is first of all because language is localized, with signal regularities (e.g., grammar, syntax) being meaningful only to in-group members. Second, there is a critical window of language acquisition that typically closes at late adolescence, and one can almost never reach native-level proficiency if the person tries to learn a language beyond that window. Thus, two people are very likely to have grown up in the same place if they speak the same language with similar high levels of proficiency. Conversely, the lack of proficiency in speaking a language suggests that one does not have the same childhood experience as others and is thus an out-group member. Because ancestral humans had recurrent exposure to people speaking different languages (or variants of the same language) even given their limited travel ability, language-based categorization appears to be an evolved part of human nature.
Evolutionary theories can also help renovate research on ethnolinguistic vitality and (non)accommodation. For example, an analysis of host-parasite coevolution suggests that maintaining and using one’s own language can help reduce the risk of contracting foreign diseases in places with high parasite stress. This is because out-group members are more likely than in-group members to carry diseases that one’s physiological immune system cannot tackle. Intergroup differentiation is thus needed more in places with higher parasite stress, and language (as noted) reliably marks group membership. It thus benefits people living in parasite-laden environments to stick to their own language, which helps them remain close to in-group members and away from out-group members. Research also shows that increases in perceived parasitic threats cause people higher in pathogen disgust sensitivity to perceive speakers with foreign accents as being more dissimilar to self. This enhanced perceived dissimilarity may cause non-accommodation or divergence in intergroup communication, resulting in negative language attitudes and even intergroup conflicts. These and many other areas of research uniquely identified by evolutionary approaches to intergroup communication research await further empirical tests.
Aspects of Luo Socialization
