A new study suggests all Australian Indigenous languages descend from one common ancestor.

The finding sheds new light on the origins of Australian language and has significant implications for the cultural history of Australia.

The study provides the first real proof for the theory that all Australian languages derive from one language - Proto-Australian.

“Until now, it was speculated that Australia was significantly more linguistically diverse than somewhere like Europe, because it had not been proven that all Australian languages actually stemmed from the same lineage,” says University of Newcastle historical linguist, Associate Professor Mark Harvey.

“This is the first demonstration that all Australian languages are part of the same language family. This language family spread across all of Australia, presumably from a small area in Northern Australia.

“This spread is likely to have been carried out by at least some population movement whose material and genetic traces have remained somewhat elusive.

“However, with further interdisciplinary research, this new linguistic evidence is likely to give us a more precise reconstruction of Australian prehistory from what is currently known,” Associate Professor Harvey said.

The project used a standard method in historical linguistics to establish whether similarity between languages was due to inheritance from a common ancestor, as opposed to transfer from one language to another through human contact or chance.

The technique revealed recurring similarities between languages that were not in contact.

“We discovered that the sounds of words we compared showed recurrent systematic differences and similarities across a set of languages that are spread out in a geographically discontinuous way - which makes it very unlikely that they are the result of chance or language contact,” Western Sydney University researcher Associate Professor Robert Mailhammer said.

“While a multitude of Australian Aboriginal and Torres Strait Islander languages were spoken at the time of European settlement, the findings also imply that Indigenous Australian languages only spread after the end of the last ice age, some 10-12,000 years ago.

“These findings show that Indigenous Australian languages were not the likely languages spoken by the first inhabitants of Australia, raising more questions around how the languages spread and how the linguistic findings connect to the genetic findings,” he added.