I used to ask elders about these things until they forbade more questions on the grounds that I was spiritually weak.
Worldwide flood-how did kangaroos get stuck on an island?
It's even more complicated than that. All indigenous mammals in Australia are marsupials. Noah would have had to drop off, not just kangaroos, but all of Australia's marsupials at the same time. And then he would have had to float about 5,000 miles back to the Middle East. Must have been some mean currents in that flood.