title: Genome-wide evidence of Austronesian-Bantu admixture and cultural reversion in a hunter-gatherer group of Madagascar.
abstract: Linguistic and cultural evidence suggest that Madagascar was the final point of two major dispersals of Austronesian- and Bantu-speaking populations. Today, the Mikea are described as the last-known Malagasy population reported to be still practicing a hunter-gatherer lifestyle. It is unclear, however, whether the Mikea descend from a remnant population that existed before the arrival of Austronesian and Bantu agriculturalists or whether it is only their lifestyle that separates them from the other contemporary populations of South Madagascar. To address these questions we have performed a genome-wide analysis of >700,000 SNP markers on 21 Mikea, 24 Vezo, and 24 Temoro individuals, together with 50 individuals from Bajo and Lebbo populations from Indonesia. Our analyses of these data in the context of data available from other Southeast Asian and African populations reveal that all three Malagasy populations are derived from the same admixture event involving Austronesian and Bantu sources. In contrast to the fact that most of the vocabulary of the Malagasy speakers is derived from the Barito group of the Austronesian language family, we observe that only one-third of their genetic ancestry is related to the populations of the Java-Kalimantan-Sulawesi area. Because no additional ancestry components distinctive for the Mikea were found, it is likely that they have adopted their hunter-gatherer way of life through cultural reversion, and selection signals suggest a genetic adaptation to their new lifestyle.
authors.affiliation: Laboratoire d'Anthropologie Moléculaire et Imagerie de Synthèse, Unité Mixte de Recherche 5288, Centre National de la Recherche Scientifique, Université de Toulouse, 31073 Toulouse, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Pierron
authors.forename: Harilanto
authors.initials: H
authors.lastname: Razafindrazaka
authors.forename: Luca
authors.initials: L
authors.lastname: Pagani
authors.forename: François-Xavier
authors.initials: FX
authors.lastname: Ricaut
authors.forename: Tiago
authors.initials: T
authors.lastname: Antao
authors.forename: Mélanie
authors.initials: M
authors.lastname: Capredon
authors.forename: Clément
authors.initials: C
authors.lastname: Sambo
authors.forename: Chantal
authors.initials: C
authors.lastname: Radimilahy
authors.forename: Jean-Aimé
authors.initials: JA
authors.lastname: Rakotoarisoa
authors.forename: Roger M
authors.initials: RM
authors.lastname: Blench
authors.forename: Thierry
authors.initials: T
authors.lastname: Letellier
authors.forename: Toomas
authors.initials: T
authors.lastname: Kivisild
mesh_terms: D000465:Algorithms; D044466:Asian People / Q000235:genetics; D044383:Black People / Q000235:genetics; D003469:Culture; D005006:Ethnicity / Q000235:genetics; D005828:Genetics, Population; D005843:Geography; D006239:Haplotypes; D006720:Homozygote; D006801:Humans; D008037:Linguistics; D008270:Madagascar; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D020641:Polymorphism, Single Nucleotide; D044382:Population Groups / Q000235:genetics*
keywords: DNA; migration; settlement