Borneo is home to a group of contemporary nomadic hunter-gatherers, the Cave Punan (Punan Batu), with a unique lifestyle and genetic make up that reflect the deep ancestry of the region. Our recent research sheds light on their genetic history and cultural heritage, offering a rare glimpse into a way of life that was once widespread in the forests of Borneo. The study combines multiple independent lines of evidence from ethnology, population genetics, and linguistic analysis to provide a cultural-genetic-linguistic axis study of the only known group of Punan hunter-gatherers who remain largely mobile. Our results challenge the prevailing notion that the Punan hunter-gatherer communities are agriculturalists who underwent recent subsistence reversion. Instead, they suggest that the community has a long history in the region. Punan Batu have long been genetically separate from nearby Indigenous agriculturalists and have experienced substantial genetic drift probably owing to a combination of cultural endogamy and long-term genetic isolation. These findings thus provide insights into the deep ancestry of Bornean hunter-gatherers and their long-term local ancestry dynamics. However, the Punan Batu's lifestyle is threatened by environmental degradation, including the slow destruction of tropical forests caused by oil palm plantations and logging. My talk will explore the genetic and cultural heritage of the Punan Batu, the implications of our research for understanding the history of human cooperation and adaptation, and the challenges faced by the last remaining hunter-gatherer group due to the environmental changes.