Admixture in Madagascar

In my spare time today I went through much of Madagascar: A Short History. After reading it I'm even more convinced that people need to stop talking authoritatively about this island and its people. There's a lot of interesting material in it, but ultimately the years before European contact remain very shadowy. I don't know much new about this period. This brings me to why I'm putting this post up: I am going to try and see if I can estimate an average age of admixture for my two Malagasy individuals. Hold me to it. I'll make time.