Continuous interactions between islands of the South Pacific, from the colonisation by populations associated with the Lapita culture 3000 years ago to European colonisation 400-300 years ago, explain the genetic and cultural diversity of contemporary local societies. This is particularly the case in South Vanuatu, where population diversity is also marked by relations with Polynesia, starting at the end of the first millennium. Our paper aims at defining human mobility in a diachronic perspective by examining several biological temporalities, from the individual to the population. To this end, we have studied the enamel structures of 21 individuals discovered in various archaeological contexts on three interrelated islands of Tanna, Futuna and Aniwa. We have applied an intra-individual approach, with sequential measurements of 87Sr/86Sr ratios by laser ablation. The technique produces results indicative of a biological temporality over a period of less than 10 years. Our first results show that most of the individuals display profiles with different amplitudes and a succession of phases that do not seem to be superimposable. We interpret these results as suggesting mobilities specific to each child, in relation to overall family mobility. Such family life histories attest to a heterogeneity of practices in terms of mobility over time and across the region.