A research group led by Professor Hirofumi Matsumura of Sapporo Medical University published the research results of human bone morphology and DNA excavated from the Gua Harimao ruins in Sumatra island in June 2018 in Plos One. The co-authors are Ken'ichi Shinoda, the research representative of the A02 team, who was in charge of the analysis of ancient human mitochondrial DNA, and Noboru Adachi, Tsuneo Kakuda, and Hideaki Kanzawa. According to the morphology of the bones, the Jomon people of Japonesia are close to the Liujiang man of China and the Mambak people of Vietnam, and the Yayoi people are close to the Negidals and Yukaghir people of Russia.