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In a first step to obtain a proxy record of past climatic events (including the El Nino- Southern Oscillation) in the normally aseasonal tropical environment of Sabah, a radial segment from a recently fallen dipterocarp (Shorea superba) was radiocarbon dated and subjected to carbon isotope analysis. The high-precision radiocarbon results fell into the ambiguous modern plateau where sev- eral calibrated dates can exist for each sample. Dating was achieved by wiggle matching using a Bayesian approach to calibration. Using the defined growth characteristics of Shorea superba, prob- ability density distributions were calculated and improbable dates rejected. It was found that the tree most likely started growing around AD 1660-1685. A total of 173 apparent growth increments were measured and, therefore, it could be determined that the tree formed one ring approximately every two years. Stable carbon isotope values were obtained from resin-extracted wholewood from each ring. Carbon cycling is evident in the 'juvenile effect', resulting from the assimilation of respired car- bon dioxide and lower light levels below the canopy, and in the 'anthropogenic effect' caused by increased industrial activity in the late-nineteenth and twentieth centuries. This study demonstrates that palaeoenvironmental information can be obtained from trees growing in aseasonal environ- ments, where climatic conditions prevent the formation of well-defined annual rings. Copyright 2004 John Wiley & Sons, Ltd.