A vanishing nomadic clan, with a song-like language

•  BRENDAN BORRELL

NEW YORK: The Punan people of the island of Borneo were once rumored to have tails, so elusive did they seem to their neighbors in the 19th century. Unlike the Indigenous farmers, who lived in long houses, the Punan roamed the island’s northern rainforest in family groups, hunting bearded pigs, harvesting starchy plants and gathering forest products for trade.

They were not only misunderstood, but mistreated. Over decades, the Indonesian government stripped the Punan of their ancestral lands and encouraged them, sometimes forcibly, to settle in ready-built villages. By the 1990s, anthropologists believed that the group’s traditional hunter-gatherer lifestyle had vanished. In 2002, a census of the Punan in eastern Borneo focused only on the villages, because so few nomads were thought to exist. And so in 2018, when Stephen Lansing, an anthropologist at the Santa Fe Institute, and Pradiptajati Kusuma, a geneticist at the Mochtar Riady Institute for Nanotechnology in Tangerang, Indonesia, said they had learned of a clan of about 30 Punan families who sheltered in limestone caves and rarely, if ever, emerged from the forest, many experts were skeptical. But with funding from the National Science Foundation, the scientists made contact with the nomadic group in 2018, and began collecting data with the aim of ensuring their health and welfare.

After that first trip, Dr. Lansing returned to Santa Fe with photographs of a man wearing a loincloth made of bark fiber, along with recordings of a song language he believed resembled no other. His initial description of these people, who call themselves the Cave Punan or Punan Batu, was published last year in the journal Evolutionary Human Sciences. Press reports in the Indonesian media catalysed the local government to declare the Punan Batu as regular users of their forest, a first step toward obtaining the right to manage it under national laws.

Some experts remain doubtful that this unusual group could really have been secluded for so long. The skeptics have compared the announcement to that of the Tasaday, a “lost tribe” discovered in the Philippines in 1971, whose isolation was eventually determined to be an exaggeration, if not a hoax.

Bernard Sellato, a Punan specialist with the French National Center for Scientific Research, has been particularly fierce in his criticism. In an email, he referred to the Punan Batu and other coastal groups as “‘fake’ Punan.” Based on historical accounts and ethnographies, he remains convinced their ancestors were not native to the island, but rather enslaved people imported from New Guinea and eastern Indonesia several centuries ago.

But a new study focusing on the DNA of the Punan Batu, recently accepted by a scientific journal, is poised to eliminate the doubts of all but the most hardened critics. Based on the limited diversity revealed in the genes of the Punan Batu, they appear to have been isolated for more than 20 generations. Dr. Sellato’s contention that the Punan Batu are the descendants of imported slaves does not fit with these results. The new findings could also put to rest a century-old debate about when the Punan arrived in Borneo, and how they became hunter-gatherers in the first place. And the research could help make the case that the Punan Batu deserve a hand in managing their forest, which is threatened by encroaching palm oil plantations and commercial forestry operations. “What they desperately want,” Dr. Lansing said, “is to stop the destruction of their forests.”