This amazing story reports the longest ever recorded dispersal event. Using genetic evidence biogeographers have proved that two populations of Acacia tree in Reunion Island (Indian Ocean) and Hawaii represent a single species. The Reunion Island population became established around 1.4 million years ago when a seed from Hawaii was transported 18,000 kilometres, probably attached or inside a bird.

The article also details some other long-distance dispersal events, but none quite as extraordinary as this one. However, these dispersal events are changing how biogeographers understanding of species distributions, with an increasing recognition of the role of chance - single rare events which have long-term and profound implications for species distributions and patterns of biodiversity.