Figure 1

Difference in mean annual temperature between the last glacial maximum (LGM; ~21 ka years before present) and present day climate (1950-2000). LGM predictions were based on the CCSM global circulation model ([10]; data available from http://www.worldclim.org). Although many intraspecific diversification events within vertebrates occurred much earlier than the LGM, the change in temperature between the LGM and present is representative of climatic oscillations over much longer timescales [11].