Some Pacific Islanders may carry evidence of an unknown human species in their DNA, according to statistical geneticist Ryan Bohlender at the University of Texas. Segments of unknown DNA were unlikely to have Neanderthal or Denisovan origins, Bohlender argued at the American Society of Human Genetics conference last week.

About 100,000 years ago, Homo sapien ancestors left Africa and made contact with other hominid species in Europe and Asia. Two of those species, Neanderthal and Denisovan, are known and documented with archeological evidence. However, scientists have found only one Denisovan finger bone and a couple of teeth in a Siberian cave in 2008.

Close

[lz_ndn video=31541006]

Researchers continue to study Denisovan DNA. Europeans do not have evidence of Denisovan ancestors, and people in China have only 0.1 percent of Denisovan DNA.

In contrast, Melanesians from Fiji, Papua New Guinea, New Caledonia, and other islands carry about 1.11 percent Denisovan in their genes. Bohlender and his colleagues believe that some of that DNA may actually come from a third, as yet undiscovered, hominid group.

Archaeologists have found scant evidence for Denisovans and no evidence of a third group. But, a separate study from the Natural History Museum in Denmark corroborated with Bohlender’s findings. Researchers looked at DNA from Aboriginal Australians and 25 islanders from Papua New Guinea. They discovered that the Aboriginal ancestry dates back 50,000 years — and that the DNA was distinct enough that it could have come from an unidentified species.

Related: Making Sleep Safe for Other Children

Bohlender’s findings have yet to receive peer review, and some of his conclusions may shift under scrutiny from the scientific community. Denisovan DNA may be more different than we think — especially since scientists have had scant relics to work with.

Nevertheless, it’s safe to say ancient human civilization was more complicated than researchers originally thought.