When marine geologist Mick O’Leary showed a group of Australian First Nations Elders a digital model of two ancient watering holes he had recently located—now under 14 meters of ocean—one man perked up, struggled to his feet and began speaking excitedly in his native tongue. Soon the whole group was talking and gesturing. O’Leary didn’t understand most of what they were saying, but did hear the phrase “half-and-half.”
The man, Timmy Douglas, had recognized the watering holes as part of a songline he’d known all his life. Songlines involve using dramatic story-songs that First Nations people began creating long before the written word as a mnemonic and spiritual system to navigate Australia’s harsh terrain by singing the songs as they walked across it. These songs, which also define groups and laws and impart cultural values, have been passed down from one generation to the next over thousands of years. Perhaps the most famous is the Seven Sisters, a saga about a shapeshifting villain who chases the titular sisters (represented by the seven stars that makeup the Pleiades) across the continent’s night sky; the song describes plains, creeks, rock formations, and more along the way. “Think of it like Google Maps,” O’Leary says, “but all in your mind.”
Douglas, who is in his 90s, had only ever seen half of the terrain described in the songline and never the half with the watering holes. This suggests that the songline may have been created more than 7,000 years ago, when the sea level was far lower—and the area with the watering holes was dry and more than 100 kilometers inland. “Whether it was inland 100 kilometers or out 100 kilometers, we still lived here,” says Vince Adams, another member of the Murujuga Circle of Elders, which governs traditional cultural knowledge in Murujuga (called the Dampier Archipelago in English). “And we still got the story to tell you.”
The connection of the songline to a recent and remarkable archeological find by O’Leary and his colleagues illustrates how First Nations groups and modern scientists are learning to work together—in this case to find evidence of the ancient humans who lived on land that is now underwater, what the Murujuga Elders call “Sea Country.” Such evidence now includes stone tools that the scientists found last year on the ocean floor near the submerged watering holes.
“It’s the oldest underwater archeology site in Australia,” says Jonathan Benjamin, an archeologist at Flinders University in Australia, and first author on a study published earlier this year in Quaternary Science Reviews that describes the find. It’s also only the second confirmed underwater archeology site in Australia. Members of the study team also found stone tools in 2019 at a nearby, shallower site called Cape Bruguieres. That site was far easier to reach than the second one, which lay at the bottom of Flying Foam Passage, a narrow channel between two islands. “It’s a very tough place to dive in because of the tidal currents,” Benjamin says. “They rip right through there.” The treacherous conditions gave him and the other scientific divers just an hour a day to search for artifacts. Funding limitations meant they had only a week to look.
“It’s an exciting study because they used super high-tech methods to make really precise maps and do this [three-dimensional] imagery of their artifacts,” says Jessi Halligan, an underwater archeologist at Florida State University, who was not involved with the study.
The team plans to further study the finds with methods including geochemical analysis. This can create a “fingerprint” of the stone used to make the tools, which can in turn connect them to a specific quarry—thus revealing the toolmakers’ movements. And a residue analysis could also be revealing, says Wendy Reynen, a stone tool specialist on the study team. “If you’re skinning a kangaroo, you might get tiny, tiny, microscopic fragments of bone and blood and skin,” she says. “That could tell us what people were doing with that specific stone tool.”
Benjamin estimates there are thousands of other potential underwater First Nations sites around Australia’s coasts. He says his group’s discoveries are forcing public officials and industry leaders to slow plans for seafloor mining and to think about ways to prevent possible damage to these sites. “Nobody [outside of First Nation’s peoples] was thinking about Indigenous sites before, or those that were doing so were told, ‘Yeah, it’s possible they exist, but you can’t focus on anything that’s possible and not proven,’” Benjamin says. “So we’ve gone from possible to proven, and the narrative is absolutely changing.”
The finds were also mentioned in the Murujuga Aboriginal Corporation’s recent application for UNESCO World Heritage Site designation. In addition to the underwater cultural heritage, the area is also home to more than one million ancient rock carvings that the council would like to protect.
These carvings, like some songlines, tell a story of people coping with sea-level rise. First Nations people arrived on the continent some 65,000 years ago, when the Last Ice Age was in full swing. After Earth began to warm some 20,000 years ago and the ocean began to swallow parts of the landscape, the carvings shifted from depictions of inland flora and fauna to fish, sea turtles and other marine life.
The stone tools found in the area might also offer new evidence about how rising sea levels affected the inhabitants of what is now Sea Country, especially if divers bring up more tools from the passage on a future research trip. The tools “are probably linked to the same people who did the engravings,” Reynen says. “But that’s all we can really say at the moment.”
The researchers’ find is also a crucial proof of concept: the grant they’d received to search for underwater artifacts was the first one given out for such work since the 1980s. “We knew if we failed, there probably wouldn’t be any more money going into this type of research,” O’Leary says. That concern led to two years of painstaking work to map the seafloor with laser and sonar scanners in an attempt to increase their odds of success.
The scientists knew watering holes would have been places where humans gathered and perhaps left behind artifacts, so when their data showed two depressions at the bottom of Flying Foam passage, they were eager to explore it.
The stone chunks that the divers brought up were encrusted with marine life, so first they had to be cleaned. Reynen then examined them for signs that a human had altered the stone to make it into a tool—for example, a sharp edge or percussion marks that showed it was hit repeatedly to alter its shape.
“I suppose the first feeling was of joy that here we found something and then quickly followed by a bit of fear—because in my culture, once these artifacts have been discarded, we can’t touch them anymore,” says Adams, who went out on the dive boat with some of the other Elders, who had granted the researchers permission to dive at Murujuga. But in this case the Elders made an exception, saying they recognized the value of documenting Sea Country’s existence for non–First Nations people.
Meanwhile O’Leary says that although the research team did not physically follow the songline to make its discovery, he thinks that kind of collaboration might happen in the near future. “We really see now you need to weave together the Western science and Indigenous knowledge, braid it together, so it’s not done as two separate things,” he says. “When these things are overlaid together, you get a more holistic picture of Sea Country.”