There was almost a literal land bridge between Australia and Asia during the Pleistocene.
Even if there wasn't a land bridge, water is the easiest way to travel, a couple strokes of a paddle and you and all your possessions and supplies glide a couple yards.
Much easier that schlepping everything on foot, and you don't have to chop your way through the undergrowth!
Yet in academe's ivory towers, a river, a lake, or a sea is an insurmountable barrier!
(upgraded tagline)
There’s also, if you do’t know, look it up (see post 8).
Australia has been separated from other land masses for millions of years.
Indeed. lol.
But my point is that these early Aboriginal ancestors need only have walked - or rowed - along the coastline until a strong west wind/storm during monsoon season - assuming such patterns existed during the Pleistocene - blew one of them beyond the pale - just one of several 'gaps', and not bigger than traversing the sea between Cuba & Florida - and the first 'new world' was discovered.
If they never went back, their isolation was assured. The rest is 'history', beginning in 1606, so-to-speak.
The human spirit of exploration and adventure is hardwired, though it is obviously stronger in some than others (others never followed them, according to the DNA)...
...and I AM referencing more than merely the physical, the true evidence for this migration having been buried by the seas thousands of years ago. But the DNA and the little clues continue to push back the limits of small minds, just like what is happening in the Americas.