Follow the breakup of Gondwana, if you can get past the awful audio (albeit, with a very pleasant Kiwi narrator)..
The movement of continental plates led to the formation of the great southern continent we call Gondwana about 200 million years ago, and began to split it apart some 30 million years later. Among the products of the breakup were the southern continents of of Antarctica, Australia, South American, and Africa - and the islands that today make up New Zealand. By more recent times, the formerly continuous land mass was a fragmented puzzle separated by vast expanses of the southern ocean. Biogeographic questions abound, including the degree to which the current flora and fauna of these derive from a Gondwanan heritage or a later dispersal to their current locations.
A new paper in the American Journal of Botany provides evidence that,for some plants at least, addresses this issue for certain components of the flora of New Zealand. Researchers led by Gregory Jordan of the University of Tasmania report on two new fossils from the heath family (Family Ericaceae) discovered in New Zealand deposits dated to the Late Oligocene/Early Miocene. That puts them between 15 million and 28 million years old. They seem to be of a different lineage than much older fossil pollen finds from New Zealand which go back to the Late Cretaceous, over 67 million years of age. The analysis of the fossils suggests that the ancient pollens represent ericacid lineages that went extinct, with the living heaths of the islands being descended from a much more recent line.
Score one for the dispersalists.
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