Sexual segregation in human conversations

Human conversation groups have a characteristic size limit at around four individuals. Although mixed-sex social groups can be significantly larger than this, census data on casual social groups suggest that there is a fractal pattern of fission in conversations when social group size is a multiple of this value. This study suggests that, as social group size increases beyond four, there is a tendency for sexual segregation to occur resulting in an increasing frequency of single-sex conversational subgroups. It is not clear why conversations fragment in this way, but a likely explanation is that sex differences in conversational style result in women (in particular) preferring to join all-female conversations when a social group is large enough to allow this.