Can you say more about this
@Mungoman?
No worries Frides.
There are a few Ancestry tales of when the land was much dryer - a lot of them were for the little'uns. This is one of 'em.
One of the the causes was a giant frog called Tiddalik who woke up angry and out of sorts one morning, and he thought that if he drank some water it would fix things, so he started drinking, and drinking, and drinking and drank all the fresh water on the Earth.
Pretty soon, things started dying.
All the animals gathered, and spoke together about the lack of water and this old wombat says to 'em...he was grumpy - that's why he drank everything, so you've got to make him laugh to get your water back.
They all tried to make him laugh but he was a miseryguts and he just sat there until a little freshwater eel came up and started to dance in front of him.
This little eel danced so hard that he kept tying himself in knots, which amused Tiddalik - pretty soon he was laughing like a drain, and all their water came pouring out of Tiddaliks mouth.
Footnote. They are all animals, not human beings, because the big flood hasn't happened yet, where Biaime's wife saves all the animals and turns them into human beings.
There is also the oral tradition of the two brothers who watched the flooding of the Spencer Gulf.
Obviously not one generation of brothers but I can surmise that the water rising must have been pretty obvious to those Old Ones because the Spencer gulf is about 75 K's across, maybe three hundred K's long and has a mean depth of only about 13 metres.
During the last Glacial maximum Australia had been inhabited conservatively for 40,000 years and the change in climate was so drastic that inland Aborigines either traveled to the coast, or perished. This was also the time of the outright end of our Megafauna.
Inland water dried up, predictable rain patterns ceased, inland forests died out, Predominant winds and climate changed direction from the west, which came across the continent, to a Southerly, straight of the Antarctic, the the majority of rain forest below the tropic of Capricorn died out along with the inland rainforest surrounding the inland Lake systems. Civilization, as the Aborigine knew it, ceased to exist.
Mean temperature dropped by 10 degrees C and the warmest area on the continent was close to large bodies of water. This wasn't the first time that the sea level had dropped.
The new land dreaming became, or was remembered from last time and was included in more recent folklore, and I reckon that this 'map' is possibly a very distant memory.
There are local myths of near marine topography all up the Eastern coast about islands that were once connected to the mainland and are predominant in the Tjukurpa (Dreaming), with some of them a bit of a hodgepodge due to the reserving of local Aborigines elsewhere.