Lost in Madagascar

This semester I'm teaching a course on the Indian Ocean, and while prepping tonight's class, I remember this Economist piece on DNA evidence regarding the original settlement of Madagascar from what is now Indonesia:

"Now, Murray Cox of Massey University in New Zealand and his colleagues have put the matter beyond doubt by showing not only where the first settlers came from, but also how many of them there were. And the answer is surprisingly few. Though Dr Cox is unable, with the method he used, to work out how many men were in the original party, the number of women was 30...

"That answer bears on a second question: was the colonisation of Madagascar a deliberate act or an accident? The first is possible. At the time, much of the Malay Archipelago was in the hands of the Srivijayan empire, an entity that could certainly have sent expeditions across the Indian Ocean, had it so willed. But there is no historical evidence that it did. In any case if it had, it is likely that a successful colonisation by one group would have been followed by others, as happened when Europeans discovered the Americas.

"Most likely, then, the first Malagasy were accidental castaways, news of whose adventure never made it back home. But there is still a puzzle. Most ships' crews are male. Though the number of men in the original party will remain obscure until an analysis like Dr Cox's is done on the Y-chromosome of Malagasy men (Y-chromosomes include DNA passed exclusively down the male line in the way that mitochondrial DNA is passed down the female line), the presence of women on board a trading vessel would have been unusual. Unless, of course, the women themselves were the objects being traded. Possibly, then, Madagascar was colonised by an errant slave ship. Which would make its history even stranger than anyone had previously thought."

Adding to this is the fact that the dating Cox arrived at is about the same as the oldest carbon dating associated with human activity on the island, which is from the eighth century with a margin for error into the seventh and ninth.  That date came from a rock shelter called Lakaton'i Anja on the north coast of the island, which had an archaeological assemblage showing that it was a base camp for hunters and gatherers who had little or no contact with the outside world.