Through next-generation DNA sequencing, archaeogeneticists can now reconstruct biological relatedness in prehistoric populations with unprecedented precision, driving a surge of research claiming to show evidence of various kinship and marriage patterns in prehistoric populations. However, both social anthropologists and archaeologists have critiqued this work for conflating biological relatedness with kinship and relying on outdated categories from classical kinship theory. Drawing on the ethnography of so-called ‘big men societies’ in the New Guinea Highlands, this presentation explores what signatures, if any, a more flexible process of social affiliation might leave in the archaeological record in order to examine whether inferences about 'patrilineal' and 'patrilocal' prehistoric populations are warranted. In doing so, it defends ethnography’s crucial role in interpreting prehistoric social organisation while demonstrating how computational modelling can bridge key debates in kinship studies.