Boabs grow native to Africa and Madagascar – and a single relative thrives in the Kimberley region of NW Australia. How did boabs reach Australia?
According to a study published in PLOS ONE – see http://phys.org/print347783892.html they were brought by Aborigine people in the remote past, carrying the seeds during their wanderings across half the world. Earlier hypothesis was that seeds were transported by waves across the Indian Ocean. Alternatively, boabs were extent on the super continent of Gondwana which split up to become Africa, Madagascar, the Antarctic and Australia – going back some 50 million years. This theory was debunked by a botanist, David Baum, who looked at the genetics of boabs and found they had split apart just 6 million years ago. However, the Gondwana split is all part of Plate Tectonics – and Drift. In other words, the genetics appears to nullify the consensus theory – which means they could very well have been transported by humans (which is the gist of the article).