If you ever watched/read the advocacy cartoon/book/Darwinian morality play "FernGully: The Last Rainforest" you might think that ruining the rainforests is a modern phenomenon brought on by McDonald's hamburgers or guitar makers or whoever and ancient man lived in harmony with nature.
It's a great mythology but just that - nature does not live in harmony with anything. Since almost the moment the last Ice Age ended, prehistoric man has kept fighting nature, including rainforests in Borneo, Sumatra, Java, Thailand and Vietnam, which had been termed 'untouched by humans.'
A new study shows that wasn't the case; the tropical forests of South East Asia have been shaped by humans for at least the last 11,000 years. The analysis of vegetation histories across the three islands and the SE Asian mainland has revealed a pattern of repeated disturbance of vegetation since the end of the last ice age. Evidence of human activity in rainforests is hard to find and traditional archaeological methods of locating and excavating sites are extremely difficult in the dense forests. Pollen samples, however, are now unlocking some of the region's historical secrets.
Dr. Chris Hunt , Director of Research on Environmental Change at Queen's University Belfast, 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.
"There is evidence that humans in the Kelabit Highlands of Borneo burned fires to clear the land for planting food-bearing plants. Pollen samples from around 6,500 years ago contain abundant charcoal, indicating the occurrence of fire. However, 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. This indicates that the people who inhabited the land intentionally cleared it of forest vegetation and planted sources of food in its place.
"One of the major indicators of human action in the rainforest is the sheer prevalence of fast-growing 'weed' trees such as Macaranga, Celtis and Trema. Modern ecological studies show that they quickly follow burning and disturbance of forests in the region.
"Nearer to the Borneo coastline, the New Guinea Sago Palm first appeared over 10,000 years ago. This would have involved a voyage of more than 2,200km from its native New Guinea, and its arrival on the island is consistent with other known maritime voyages in the region at that time – evidence that people imported the Sago seeds and planted them."
The findings have importance for ecological studies as the historical role of people in managing the forest vegetation has rarely been considered.