Check out this: “Backtracking Birds Show Islands are not Evolutionary Dead End” on the blog A Scientific Life (or Scientist, Interrupted), aka girlscientist.blogspot.com. The post reports on a paper on bird biogeography published in Nature, “Single origin of a pan-Pacific bird group and upstream colonization of Australasia.” The main point of the paper is that the biogeogaphy of a group of pacific island monarchs is not a simple matter of flow from the continental source to the island sink; instead, there has been some back-and-forth over the last few million years.
It is interesting that despite all the hop-scotching about, there is still (intuitively) a pretty significant correlation between phylogenetic relationship and geographic proximity).
I think this kind of study hints that a real revolution in biogeography is coming. Imagine if you were to do this study not just on one bird group, but on all the lineages you could get your hands on, say, 50 different groups, each with representatives on some of the islands. Clearly there would be a lot of “noise” as different groups dispersed in different directions. But you might start to really be able to get a quantiative handle on the long-standing questions in biogeography – dispersal vs. vicariance, speciation in situ vs. ecological invasion, and whether or not “centers of distribution” really are species factories, or just temporary ecological assemblages. Hmm, sounds like a PhD project. Anyone know a good program, probably an evolution program, where a guy like me could do not just phylogeography on one group, but what I hereby dub “comprehensive phylogeography”? (Preferrably on plants. Plants are cool.)