Data from: Functional traits as predictors of vital rates across the life cycle of tropical trees

The ‘functional traits’ of species have been heralded as promising
predictors for species’ demographic rates and life history. Multiple
studies have linked plant species’ demographic rates to commonly measured
traits. However, predictive power is usually low – raising questions about
the practical usefulness of traits – and analyses have been limited to
size-independent univariate approaches restricted to a particular life
stage. Here we directly evaluated the predictive power of multiple traits
simultaneously across the entire life cycle of 136 tropical tree species
from central Panama. Using a model-averaging approach, we related wood
density, seed mass, leaf mass per area and adult stature (maximum
diameter) to onset of reproduction, seed production, seedling
establishment, and growth and survival at seedling, sapling and adult
stages. Three of the four traits analysed here (wood density, seed mass
and adult stature) typically explained 20–60% of interspecific variation
at a given vital rate and life stage. There were strong shifts in the
importance of different traits throughout the life cycle of trees, with
seed mass and adult stature being most important early in life, and wood
density becoming most important after establishment. Every trait had
opposing effects on different vital rates or at different life stages; for
example, seed mass was associated with higher seedling establishment and
lower initial survival, wood density with higher survival and lower
growth, and adult stature with decreased juvenile but increased adult
growth and survival. Forest dynamics are driven by the combined effects of
all demographic processes across the full life cycle. Application of a
multitrait and full-life cycle approach revealed the full role of key
traits, and illuminated how trait effects on demography change through the
life cycle. The effects of traits on one life stage or vital rate were
sometimes offset by opposing effects at another stage, revealing the
danger of drawing broad conclusions about functional trait–demography
relationships from analysis of a single life stage or vital rate. Robust
ecological and evolutionary conclusions about the roles of functional
traits rely on an understanding of the relationships of traits to vital
rates across all life stages.