Stoneking and colleagues compared the genetic diversity of the Mlabri with that of six other agriculture-based hill tribes. Not only did all of the other hill tribes show "significantly higher" variation, but this lack of variation hasn't been found in any other human population, indicating a "severe reduction in population size" for the Mlabri. This reduction likely happened 500 to 800 years ago, Stoneking and colleagues conclude, and at most 1,000 years ago. But how? Since genetic analyses can't distinguish between a population bottleneck and a founding event, the authors used simulations to calculate the amount of population reduction required to completely eliminate mtDNA diversity, arriving at "not more than two unrelated females" and "perhaps even only one." Linguistic studies suggest that the Mlabri language arose after speakers of a related language, probably Tin, split off and came into contact with another, as yet unknown language, an event that likely happened less than 1,000 years ago.
The genetic and linguistic evidence indicates that the Mlabri were "founded" between 500 to 1,000 years ago by one female and one to four males from an agricultural culture. W
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