Our Gondwana Heritage

Losing leaves in autumn (fall) is a response to long, dark winters. Deciduous trees are unable to photosynthesise at such times due to the lack of sunlight, so they shut down until spring. But as Gondwana split and Australia drifted northward on its own, its winters became lighter. Other groups of plants, including eucalypts, started to dominate a drier, sunnier Australia.

These more common Australian trees handle winter cold by other methods, such as developing the small, waxy leaves that are common in snow gums and other alpine plants. Only in the remote, wet highland areas of Tasmania - where losing leaves is still a good defence against winter frosts and snow - has this rare southern beech (Nothofagus gunnii) survived to thrill visitors each autumn (April/May).