Linguistic clues suggest that the Indonesian colonizers directly sailed to Madagascar

The Malagasy language belongs to the Austronesian Family and it is particularly close to some of the languages spoken in Indonesia, a fact that was first noticed at the beginning of the XVIIth century. The link to a precise Indonesian language is due to Dahl who, in 1951, firmly established a striking kinship with Maanyan, spoken in the South-East of Kalimantan. The introgression of Bantu terms is extremely limited, on the contrary the genetic makeup of the Malagasy people is African and Indonesian with comparable proportions. While genetics and linguistics agree that the colonization of Madagascar by Indonesian sailors took place in the second half of the first millennium, they disagree concerning the role of East-Africa in this event. Here we show that the dichotomy emerges because linguistics uses qualitative arguments where genetics has a consolidated tradition in the use of quantitative methods. After having collected the largest and most complete existing dataset for Malagasy, covering the entire island (207-terms Swadesh lists of 60 different dialects), we adopt new quantitative tools that allow us to confirm the genetics point of view that Indonesian sailors directly colonized Madagascar, without the East-African stopover conjectured in various studies in linguistics. The key point of our approach is the analysis of the geographical distribution of the degree of Bantu languages contamination of Malagasy dialects.