What is an example of how isolation has affected the Australian ecozone?

Isolation has significantly influenced the Australian ecozone by fostering unique biodiversity, with many species found nowhere else on Earth. For instance, the marsupial population, including kangaroos and koalas, evolved in relative seclusion, leading to distinctive adaptations suited to Australia's varied environments. This isolation has also resulted in a high level of endemism, where plants and animals have developed in response to the continent's specific climate and ecological conditions, making Australia a hotspot for evolutionary studies and conservation efforts.