This is an updated version of a previous image that only showed bearing. Click here for a full size image.
In the upper figure, older (blue) branches cluster across ocean basins (disjucntions driven by continental drift) and within continents (endemic clades). Older branches are more common within and between the southern "Gondwanan" continents than those in the northern hemisphere. There is a paucity of north-south oriented branches in the northern hemisphere that may well refect how Pleistocene climate change has driven species ranges in this region.
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