8.2 Austronesian
The next significant expansion started from the southeast and was much more dramatic. Taking our cue from the family of languages with which it is associated, we can call it the Austronesian expansion. Like the Eskimo migration, it was the work of a prehistoric Stone Age population, and we have to reconstruct it from a combination of linguistic, archaeological, and—more recently—genetic testimony. This evidence combines to reveal a process of eastward migration from island Southeast Asia into the Pacific starting in the second millennium B.C. and reaching Easter Island at the eastern limit of Polynesia around A.D. 500. As we saw in earlier chapters, correlations between linguistic, archaeological, and genetic evidence can be messy. But in this case much of the icture is unusually simple. East of the satellite islands of New Guinea, there had been no earlier human presence, and there is likewise no indication of later migrations from the west on a significant scale. So here the spread of the Austronesian language family, the appearance of the Stone Age Lapita culture or its later derivatives, and the arrival of a particular subset of human genes, can confidently be ascribed to one and the same event. Where the expansion first began is not quite so clear. Linguistic and archaeological evidence would support a homeland in southern China—or, more specifically, in Taiwan, where very diverse Austronesian languages are still spoken among the aboriginal population; but currently the genetic evidence does not sit well with this.
Like the Eskimos, the Austronesians had a material culture notable for its maritime specialization, which in their case was of course tropical rather than Arctic. Moreover, reconstruction of the vocabulary of the protolanguage spoken by the Austronesians outside Taiwan reveals an equivalent of the Indo-   European horse and cart: the outrigger canoe (the outrigger is attached to the canoe to keep it from rolling over). With this relatively simple vessel, the Austronesians of island Southeast Asia colonized an environment that has no parallel anywhere else on the globe, the innumerable small islands of the southern Pacific. But they settled few islands of any size; New Zealand and, far to the west, Madagascar were the exceptions. Likewise, they did not reach the Americas, and, a little more surprisingly, they scarcely impinged on Australia. As a result, the impact of the Austronesian expansion was more extensive than intensive.