Abstract
Cross-species analyses of plant functional traits have shed light on factors contributing to
differences in performance and distribution, but to date most studies have focused on
either leaves or stems. We extend these tissue-specific analyses of functional strategy
towards a whole-plant approach by integrating data on functional traits for 13 448 leaves
and wood tissues from 4672 trees representing 668 species of Neotropical trees. Strong
correlations amongst traits previously defined as the leaf economics spectrum reflect a
tradeoff between investments in productive leaves with rapid turnover vs. costly physical
leaf structure with a long revenue stream. A second axis of variation, the !stem
economics spectrum", defines a similar tradeoff at the stem level: dense wood vs. high
wood water content and thick bark. Most importantly, these two axes are orthogonal,
suggesting that tradeoffs operate independently at the leaf and at the stem levels.
By simplifying the multivariate ecological strategies of tropical trees into positions along
these two spectra, our results provide a basis to improve global vegetation models
predicting responses of tropical forests to global change.