Current Biology Vol 17 No 15a ‘speciation pump ’ that caused

species to diverge while isolated in small refugia [2,3], many recent studies suggest that most evolutionarily distinct groups diverged from their nearest relatives long before the Pleistocene glaciations [4–7]. As they recently reported in Current Biology, Carstens et al. [8] took a novel synthetic approach to this question — combining analyses of selection may cause wide variation in substitution rates over different time scales, making it even more difficult to test phylogeographic hypotheses using a molecular clock. These problems have led some to predict a bleak future for biogeography as a discipline. However, phylogeographers have recently gained two new powerful tools with which to explore past spatial andHistorical Biogeog Synthesis Since Darwin first noted the impact o organisms, biogeographers have de glaciations shaped evolutionary patt genetics and palaeoclimatology pro Pleistocene evolutionary history