The dingo, Australia's wild dog, was first spotted on the northwest shores of the subcontinent in the late seventeenth century. The arrival of the dingo brought about substantial changes in the continent's ecosystem. It is noted that with the establishment of dingoes, native predators declined. Among the animals probably displaced from the mainland by the dingo was the Tasmanian tiger, a recently extinct wolf-like marsupial.
1. What is the main point the author makes in this passage?