Rapoport's rule states that geographical range size increases from the
tropics towards the poles. We test this rule using data on Australian
mammals and find that it does not hold. Latitudinal and longitudinal
patterns in mammal range size correlate with continental width. Howeve
r, there are clear relationships among range size, species richness, v
egetation and climate. The arid centre of Australia contains the fewes
t mammal species, with the largest ranges, whereas the moist and mount
ainous east coast, and the monsoonal north, contain large numbers of s
pecies with small ranges.