Rain Forest Biology and the Canopy System, Sarawak, 1992–2002 The rain forest takes an immense breath and then exhales, once every four or ?ve years, as a major global weather pattern plays out, usually heralded by El Nin ˜o–Southern Oscillation. While this powerful natural cycle has occurred for many millennia, it is during the past decade that both the climate of Earth and the people living on it have had an increasing in?uence on the weather pattern itself, with many biological consequences. In Southeast Asia, as also in most of the Neotropics, El Nin ˜o accompanies one of the most exuberant o- pourings of nature’s diversity. After several years of little activity, the incredibly diverse rain forests suddenly burst into ?ower—a phenomenon referred to as General Flowering in Asia. Plant populations are rejuvenated and animals are fed, but the process involves a delicate and complex balance. When the canopy access system was under construction at Lambir Hills - tional Park in the early 1990s, it made use of an underlying technology that was already in place: bridges. For centuries, bridges have spanned the natural chasms over rivers. This existing network of bridges and the people who built and use them produced the technology we needed to gain access to the canopy. Bridge builders were our natural allies in the quest for biological knowledge of the high canopy.