I flew into Tawau, a coastal town in south-eastern Borneo, and met Glen Hernaez, who was to be the tour guide for the rest of my stay. I followed Glen and the others in the group up a hill, stepping over tree roots, scrambling up the steep volcanic slope, and trying to keep pace. Although the 28,000-hectare Tawau Hills Park, a forested reserve, was a mere 20 minutes from town, there were hardly any other tourists along the way. After a 900-metre hike, we came to a stop in front of a mammoth, smooth-trunked tree. Buttresses, snaking in every direction, propped up the world's tallest tropical tree. Called the giant Mengaris tree, its crown, visible through gaps in the canopy, towered 88.32 metres above the ground. Another giant nearby was reported to be a wee 16 cm short.