Would animals similar to Australias fauna have existed in Antarctica before the continents split?
Yes and no! There would not have been animals like what you see today in Australia, as they only evolved later, but the animals existing in Australia before the split would have also lived in nearby parts of Antarctica at the same time. Antarctica would have provided a way for animals to migrate between the continents that made up Gondwana and Australia, and there would have been some animals that migrated, but others that didn’t! Unfortunately, most of Antarctica is under large ice sheets, so it is difficult to look for fossils there, but the ones that have been found suggest some exchange of fauna.
