Australia

Twice, during a 125 million year period beginning 400 million years ago, the geosynclines were compressed, forming mountains and initiating volcanos. Volcanic activity recurred along the Great Dividing Range 20-25 million years ago during the Miocene epoch when early apes evolved as well as seals, dolphins, sunflowers, and bears. However, over millions of years the volcanic cones from this epoch have been stripped down by erosion. Still, volcanic activity persisted in South Australia until less than a million years ago. In Queensland, near Brisbane in the south and Cairns in the north of the state, the Great Dividing Range hugs the coast, creating beautiful Riviera-like vistas.

East of the Great Dividing Range, along Australia's narrow eastern coastal basin are its two largest cities, Sydney and Melbourne, as well as the capital, Canberra. The Dividing Range tends to trap moisture from easterly weather fronts originating in the Pacific Ocean. The Range is also coursed by rivers and streams. West of the Range the landscape becomes increasingly forbidding and the weather hot and dry.