The question, for an Ark believer, is: how on earth did all the marsupial mammals go straight to the Australian continent right after the Flood, and ONLY in Australia? Did god's Spaceship transport them? The same question applies to all the indigenous species of far-away islands.
When I was researching my doubts, I tried to look up on Insight volumes. I, thought something would have been written. And it was written, alright. That's what I read, in the article about flood or sth, as I recall it:
"Some raise the objection about how could all those animals from Noah's Ark go to their respective habitats after, some of which were far away in different continents. However, in the past, geologists tell us that continents were linked by "land bridges". The animals could have crossed from there". (italics mine)
The "land brigdes" that the passage said form gradually over the course of millions of years, but Noah's flood supposedly happened 4,300 years ago. At that time, the geology of the Earth was roughly the same as it is now! That made me realize that the WT deliberately used the phrase "in the past" to tell a half-truth, in other words, to willfully deceive its readers. That realization shattered my faith in the WT borg. They weren't just mistaken, they were deliberate liars.