Regarding the timeline and Tasmania, the discussion needs to include all of Australia and the dated artefacts which include rock wall drawing pointing to Africa then European influence.
Professor Eske Willerslev of the University of Cambridge sequenced the genome of 83 Aboriginal Australians from the Pama-Nyungan-speaking language group, which covers 90 per cent of the continent, and 25 Highland Papuans.
Australian co-author, Dr Michael Westaway of Griffith University said the study showed evidence only for one colonisation event in Australia, and continuity of occupation from that genomic signature for 40,000-odd years.
It reveals Papuan and Aboriginal ancestors left Africa around 72,000 years ago and then split from the main group around 58,000 years ago. They reached the supercontinent of ‘Sahul’ that originally united Tasmania, Australia and New Guinea around 50,000 years ago, picking up the DNA of Neanderthals, Denisovans and another extinct hominin along the way. Papuans and Aboriginals then split around 37,000 years ago, long before the continents including were finally cut off from each other around 8,000 years ago with Tasmania separation at 10,000 years.
The researchers suggest although Australia and New Guinea remained connected until the early Holocene, the flooding of the Carpentaria basin (Queensland & Northern Territory) and its increasing salinity may have promoted population isolation. Professor David Lambert, said the point of entry into Australia was still unclear, but the data revealed an expansion of people from Cape York.
“What our data shows is not so much that necessarily there was an entry point into the continent via Cape York, but what it shows us is that there was a divergence of a whole lot of people from Cape York, we think about 30,000 years ago,” he said.
But now testing of artefacts in an island cave in northern WA has established some of the oldest occupation dates recorded in Australia, proving Aboriginal Australians were living in the now largely submerged northern coast **50,000 years ago.**Aboriginal Australians also have genetically mixed with Denisovans at 44,000 years." This is the timelines