The divergence times reported here correspond with a series of changes in the Australian anthropological record between 5,000 years ago and 3,000 years ago, including the introduction of the dingo ; the spread of the Australian Small Tool tradition ; the appearance of plant-processing technologies, especially complex detoxification of cycads ; and the expansion of the Pama-Nyungan language over seven-eighths of Australia . Although there is no consensus among anthropologists, the former three changes may have links to India, perhaps the most relevant of which is the introduction of the dingo, whose ocean transit was almost certainly on board a boat. In addition, Dixon  noted some similarities between Dravidian languages of southern India and Pama-Nyungan languages of Australia.While this argument makes sense, it's not definitive, so there's no point in pinning ourselves down to the mid-Holocene immigration (or invasion) date suggested above. Regardless, the notion that an aggressive, largely or completely male group with an Australoid morphology arrived in Sahul/Australia to confront a largely non-aggressive, non-violent population already established in the most favorable places, could go a long way in accounting for the picture we now see in both Australia and New Guinea.
+The picture for Australia was "corrected" by Hudjashov et al , who discovered two new C haplogroups in Australia, C4a and C4b. But they don't say whether or not this directly contradicts what Redd et al claim to have found, i.e., a significant presence of C* in Australia, and a 2% presence in India, among tribal groups likely to have Australoid morphology. In fact the Hudjashov group's discussion of the Y haplogroups is confined to only a single paragraph and is incomplete and also vague. They claim their evidence is inconsistent with Huxley, who lived in the 19th century, but make no reference to Redd et al, whose study dates from only a few years prior to theirs. Regardless of their discoveries regarding C4a and C4b, the real question is the status of C*. And even if C* has been superseded in Australia by C4a and C4b, that still does not rule out a connection between India and Australia, it just makes it more difficult to prove.