The Lost Giants of Tasmania

摘要

New evidence reveals that megafauna survived in Tasmania until soon after a land bridge across Bass Strait enabled humans to cross from the mainland. Australians think of Tasmania as our largest island, isolated from the mainland by the often stormy waters of Bass Strait. While this is true for the past 14,000 years, during glacial periods in the Earth's history - when ice sheets in the Northern Hemisphere expanded greatly and sea levels around the world fell by up to 130 metres - the emergent floor of Bass Strait provided a land bridge between the "Apple Isle" and continental Australia. The most recent connection started about 43,000 years ago, instigating a chain of events that have had dramatic repercussions for Tasmania's ecology. By 43,000 years ago humans had already colonised most regions of mainland Australia for many millennia, but the island to the south remained unoccupied. However, the new land bridge presented the first opportunity for people to walk across to Tasmania.