Emma Marris, reporting for Nature News:
In what is probably the farthest single dispersal event ever recorded, researchers have shown using genetic analysis that an acacia tree endemic to Réunion Island in the Indian Ocean is directly descended from a common Hawaiian tree known as the koa. In fact, these two trees on small specks of land on opposite sides of the globe turn out to be the same species.
The event is remarkable not just for the sheer distance covered — some 18,000 kilometres, almost the farthest apart that any two points on land can be — but that it occurred between two small islands.