The idea of 'monsters' of all kinds have always fascinated me. As the article mentions, it's only in the extremely recent past (last couple of hundred years) that extinction was recognised as even something that was possible.
We normally think of extinct megafauna as something that existed in prehistoric times - literally, before we invented writing, but the word here is often by the layman used to mean "before we invented conscious thought". Many Aboriginal Dreamtime stories (so, within the last 80k years) are thought to involve now-extinct megafauna, other large creatures are known to have gone extinct only in the last 2-3000 years, untold small species have disappeared in the last ~200 years... it's hardly surprising that humans are such a superstitious bunch, considering we're only ~8 generations away from huddling in a village, frightened of the wolves and anything else that goes bump in the night.
>Tasmania, which is sometimes said to hang beneath Australia like a green jewel
...we don't say that. I don't think even Tasmanians say that. They're too busy trying to convince everyone not avoid the place so they can enjoy it.