Guardian.UK: Tests on Captain Cook's sweet potato fuel row over how crop reached Polynesia.

The research reveals that the sweet potato evolved just once, probably in central or northern South America, and originated from a single ancestor. What’s more, an analysis of a 250-year-old sample of sweet potato collected during Captain Cook’s voyage to the South Pacific on HMS Endeavour suggests the spuds arrived in Polynesia by means of ocean currents.

Islands, we continue to discover, are not the isolated places we (for so long) believed.