Plant functional trait variation in tropical forests results from taxonomic differences in phylogeny and associated genetic differences. as well as, phenotypic plastic responses to the environment Accounting for different components driving plant functional trait variation is important for understanding the potential rate of change of ecosystems since trait acclimation via phenotypic plasticity is very fast compared to shifts in community composition and genetic adaptation. We here applied a statistical technique todecompose the relative role of phenotypic plasticity, genetic adaptation and phylogenetic constraints. We examined typically obtained plant functional traits, such as wood density, plant height, specific leaf area, leaf area, leaf thickness, leaf dry mass content, leaf nitrogen content and leaf phosphorus content. We assumed that genetic differences in plant functional traits between species increases with geographic distance, whereas trait variation due to plastic acclimation to the local environment is independent of spatial constraints. Results suggest that most of the observed trait variation could not be explained by a single component, thus indicating a limited potential to predict individual plant traits from commonly measured environmental variables. However, we found a non-uniform response between different plant tissues in accordance with the plant economic spectrum, such that leaf traits varied in response to canopy light regime and nutrient availability, whereas wood traits were related to topoedaphic factors and water availability. Our analysis furthermore indicated differences in the functional response between coexisting tropical tree species, such that endemic species with conservative ecological strategies appear especially prone to competitive exclusion under projected climate change.