And what does this protolinguistic socio-semiotic system have to do with social organisation?
Well, as Halliday & Matthiessen (1999: 612) point out, the microfunctions of human protolanguage foreshadow the metafunctions of language, though there is no direct correspondence, and it is the interpersonal metafunction that creates social relationships (op cit: 511).
The inner and outer dimensions that define the microfunctions each display a contrast that can be interpreted as metafunctional, and it is desideration — termed ‘action’ in publications before Halliday (1992) — and the intersubjective that align with the interpersonal metafunction (1999: 523, 525, 612).
With regard to the intersubjective, they note that the interactional microfunction (intersubjective cognition) is a means of enacting social relationships, and we can add that in other species, such as rainbow lorikeets, the regulatory microfunction (intersubjective desideration) provides a daily means of constantly “renegotiating” one’s place in the dominance hierarchy of the social group.