Rainforest dwellers in South East Asia could have a new weapon in their battle against eviction for logging companies, a study by British experts showed.
Their land rights are often not recognised on the grounds that they are nomads who leave no permanent mark on the landscape.
Pollen sample researchers in Belfast and Cambridge have unearthed evidence of management of forests since the end of the last ice age, including setting fires to clear vegetation and planting fruit trees instead.
Dr Chris Hunt from Queen's University Belfast (QUB) said: "This provides good evidence that they ought to be treated not just as feckless savages but as people who led organised lives, depending on the resources there and actually managing them.
"Given that we can now demonstrate their active management of the forests for more than 11,000 years, these people have a new argument in their case against eviction."
Large-scale tree logging has affected partly-nomadic groups like the Penan in Borneo since the late 1970s. More recently the creation of palm oil and acacia wood plantations has had an impact.
Since the 1980s various Penan groups have campaigned against the clearances, erecting blockades. The situation was raised in the UN general assembly and the Rio earth summit.
Dr Hunt added: "I do hope that this is something that can be used by rainforest people who are fighting logging companies. It is a very clear sign that they are not just nomads who leave nothing."
Dr Hunt, director of research on environmental change at Queen's, said: "It has long been believed that the rainforests of the Far East were virgin wildernesses, where human impact has been minimal.
"Our findings, however, indicate a history of disturbances to vegetation. While it could be tempting to blame these disturbances on climate change, that is not the case as they do not coincide with any known periods of climate change.
"Rather, these vegetation changes have been brought about by the actions of people."
His research found that inhabitants of the Kelabit Highlands of Borneo burned fires to clear the land for food-bearing plants. Pollen samples from around 6,500 years ago contain charcoal, indicating fire.
"While naturally occurring or accidental fires would usually be followed by specific weeds and trees that flourish in charred ground, we found evidence that this particular fire was followed by the growth of fruit trees," he added.
"This indicates that the people who inhabited the land intentionally cleared it of forest vegetation and planted sources of food in its place."
Nearer the Borneo coastline, the New Guinea Sago Palm tree first appeared more than 10,000 years ago, the study showed.
The researchers said this would have involved a voyage of more than 2,000 kilometres from its native Pacific island and its arrival on Borneo is consistent with other known voyages in the region at the time and evidence that people imported and planted Sago seeds, including the Penan.
Their full article was published in the Journal of Archaeological Science.