Comparing Australian Ecosystems to Those ElsewhereWhat is the significance of evolutionary history

No one doubts that ecosystems are strongly influenced by their present-day physical context. Changes along environmental gradients are to be seen all around us. But how important is the long evolutionary history that shaped the biology of component species and led to those components assembling at a particular place? To tackle this question we must compare parts of the world that have similar present-day environments but different histories. Australia is a key laboratory for this natural experiment because much of its biota has had an evolutionary history separate from most other continents, and because it provides a wide range of environments. A variety of aspects of ecosystems have been compared between Australia (Figure 1) and elsewhere. An overview of these comparisons can ask which aspects of ecosystems depend on evolutionary history and which aspects are converAustralia is a key laboratory for this natural experiment