The first known human inhabitants of the Australian continent and its neighboring islands are the indigenous Australians which describes both the Torres Strait Islanders and the Aboriginal People.

Indigenous Australians are recognized by scientists to have arrived sometime in 65,000 years ago, but a lot of its oldest archaeological sites are now submerged underwater.

Recently, Smithsonian Magazine reports of a discovery that is a 7,000-year-old site submerged along the continental shelf of Australia, an encouraging sign that the Aboriginal artifacts and landscapes may have been preserved.

Australia's Aboriginal History

The end of the ice age 12,000 years ago was marked by the melting of glaciers and rising of sea level which drowned one-third of Australia's habitable land. Jonathan Benjamin, a professor of maritime archaeology at Flinders University in Adelaide, led a team that searched for marine sites off Murujuga - a dry and rocky coastal region in northwestern Australia- as part of the project called Deep History of Sea Country.

Many archaeological sites can be found in that area, including more than one million rock art samples. About 18,000 years ago, the sea level was 80 meters lower than they are today, adding a staggering two million square kilometers.

But Benjamin and his team were going on to an area completely cold of the probability of discovering anything. "So we just figured if we could throw every bit of technology and a lot of smart people at the problem, after three years, we should come up with something," Benjamin says.

At first, the team of researchers used LiDAR-mounted airplanes and sonar-equipped boats to scan the shallow seas of Murujuga to see if any areas might have the right conditions for the preservation of artifacts.

In 2019, divers surveyed the identified targets and did not find anything from the designated sites not until they looked into Cape Bruguieres Channel.

Chelsea Wiseman, a doctoral student at Flinders University, recalled when she and her colleague, John McCarthy, found some igneous rock stone tool while swimming through the turquoise water.

"The first one he handed me was just unmistakably a lithic artifact," said Wiseman. "Then we found four or five others."

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Aboriginal Artifacts and Landscapes

The team found a total of 269 stone artifacts at Cape Bruguieres Channel, buried eight feet below the water which includes various tools for scraping, cutting and hammering. They also found one grindstone that may have been used for crushing the seeds of Spinifex frass for baking into bread.

Using radioactive carbon dating and an analysis of when the area was submerged, they think that the artifacts are at least 7,000 years old.

Meanwhile, the second site, Flying Foam Passage, is a freshwater spring about 45 feet below sea level and where they found at least one stone tool that is at least 8,500 years old.

Wiseman said that their discovery would help indicate that there is more to be found offshore of the history of the Aborigines.

According to marine geo-archaeologist, Nicholas Flemming of the UK's National Geography Center, the discovery is the first time that any marine sites older than 5,000 years have been found. It proves that stone tools can survive on the seafloor in tropical environments.

Benjamin hopes that their discovery from Murujuga will impact public policy regarding maritime heritage in Australia that has many offshore energy developments but has not given much protection for underwater landscapes with Indigenous archaeology.

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