Ancient remains found in Indonesia belong to a vanished human lineage

The jaw and skull of an ancient Toalean woman were discovered in a cave in South Sulawesi in Indonesia. (Image credit: Hasanuddin University)
A new genetic analysis revealed that a woman who was buried in Indonesia 7,200 years ago belonged to an unknown human lineage.

Researchers discovered that the ancient woman was a distant relative to present-day Aboriginal Australians, Melanesians and Indigenous peoples on the west Pacific islands. These were the first humans ever to reach Oceania.

Researchers found that the woman was a descendant of the archaic human race known as the Denisovans. This contrasts with other Southeast Asian hunter-gatherers, like those in Laos or Malaysia, who don't have much Denisovan ancestry. Cosimo Posth, study co-leader and professor at the Senckenberg Centre for Human Evolution, Palaeoenvironment, University of Tbingen, Germany, stated that this is a stark contrast to other Southeast Asian hunters-gatherers, such as Laos and Malaysia.

These genetic discoveries indicate that Indonesia and its surrounding islands (an area called Wallacea) was "indeed, the meeting point for [mating] events between Denisovans on their initial voyage to Oceania," Posth explained to Live Science via email.

Related: Denisovan gallery - Tracing the genetics and ancestors of human beings

Wallacea has been a long-time interest for researchers. It is believed that Wallacea was visited by ancient people at least 50,000 years ago, possibly even before 65,000 years. This would have been before they arrived in Australia and the surrounding islands.

This map shows Wallacea which covers parts of Southeast Asia. It also includes an insert image for the province of South Sulawesi. (Image credit: Kim Newman)

In 2015, researchers discovered the burial of the mysterious woman in Leang Panninge cave on Sulawesi island. In 2015, researchers discovered the mysterious burial of the woman in Leang Panninge cave on the Indonesian island of Sulawesi.

Image 1 of 10 Leang Panninge cave, South Sulawesi. (Image credit to Leang Panninge Research Team) Image 2 of 10. The Toalean women's skull fragments. (Image credit Hasanuddin University). Image 3 of 10. The pelvis of an ancient Toalean woman. (Image credit Hasanuddin University). Image 4 of 10. The ancient woman was placed in a flexed posture for her burial. Image credit: Hasanuddin University. Image 5 of 10. Excavations at Leang Panninge Cave in South Sulawesi. Image 6 of 10. Researchers excavate the burial of a 7,200-year-old woman at Leang Panninge. (Image credit to Leang Panninge Research Team) Image 7 out of 10 Toalean Stone Arrowheads (Image Credit: Basran Burhan). Image 8 of 10, Toalean Stone Arrowheads with Pressure-Flaked Serrations (Image Credit: Yinika L Perston). Image 9 of 10. A stone arrowhead from an ancient Toalean Culture (Image Credit: Shahna Britton, Andrew Thomson). Image 10 of 10. A digital 3D model the ancient Toalean woman discovered in Sulawesi. (Image credit: David P. McGahan)

An anatomical analysis revealed that the researchers had studied her ancient DNA. This was found in her inner ear bone. "This is a significant technological achievement, because we all know that ancient DNA doesn't preserve well in tropical areas," Serena Tucci, assistant professor of Anthropology at Yale University, and principal investigator for the Human Evolutionary Genomics laboratory there, said. "This was possible only a few years back," said Serena Tucci, an assistant professor of anthropology at Yale University and principal investigator of the Human Evolutionary Genomics lab there.

Researchers added that this was the first time that researchers had studied an ancient human genome in Wallacea.

Posth stated that the woman's DNA showed she was identically related to current-day Aboriginal Australians as well as Papuans. Brumm pointed out that her lineage was separated from the populations at an earlier time.

The researchers also noted that the woman's lineage does not appear to exist today, which makes it a "previously undiscovered divergent human lineage". Brumm explained that the genome of this ancient Toalean woman is "unique to any modern people or groups that have been studied from the ancient past."

According to the genome of this woman, however, researchers did not find any evidence that modern Sulawesi are descendants of Toalean hunter/gatherers.

Researchers speculate that the Toalean woman may have had a local ancestry through ancient people who lived in Sulawesi prior to Australia and the surrounding islands.

Tucci stated that the study was "very fascinating and fascinating" in an email to Live Science.

She said, "We are discovering that there was a previously undiscovered population that migrated through this region, probably around the same time that the ancestors in Papua and Australia." Tucci stated that even though the lineage of this woman has disappeared, "all these population coexisted until relatively recent which opens up lots to lots questions about population interactions both from a genetic and cultural perspective."

The study was published online in Nature on Wednesday, August 25th.

Original publication on Live Science