The contrasting hydraulic traits observed among different plant life forms are shaped by entangled environmental and evolutionary processes. However, we lack an understanding of the relative importance of life form, climate and phylogeny in explaining the variance of hydraulic traits. We analyzed seven hydraulic traits and eleven climatic variables of 150 Fabaceae species representing three life forms from 62 sites worldwide, using phylogenetic comparative analyses and variance partitioning. The phylogenetic signal found in most traits disappeared after considering life form, indicating that phylogenetic conservatism in traits originated from the divergence among life forms. The trait-climate relationships were also phylogenetically dependent, implying that trait responses are driven by climate and phylogeny together. Variance partitioning showed that phylogeny and climate explained greater trait variation than life form did. Synthesis. The climate-driven hydraulic trait responses in Fabaceae still existed with phylogeny being considered, suggesting that this large family may be particularly sensitive to climate change. Our results emphasize the need to include phylogeny in plant hydraulic adaptation studies under future climate change.

# Table S1. Full dataset used in this study ## Description of the data and file structure Coversheet includes paper title; MetaData lists the abbreviation, full name and unit of all the variables; RawData is the raw data with references listed; any missing values are shown as "NA" to minimize ambiguity; Reference is the full reference list and data sources.