Cell wall thickness has phylogenetically consistent effects on the photosynthetic nitrogen-use efficiency of terrestrial plants.

Leaf photosynthetic nitrogen-use efficiency (PNUE) diversified significantly among C species. To date, the morpho-physiological mechanisms and interrelationships shaping PNUE on an evolutionary time scale remain unclear. In this study, we assembled a comprehensive matrix of leaf morpho-anatomical and physiological traits for 679 C species, ranging from bryophytes to angiosperms, to comprehend the complexity of interrelationships underpinning PNUE variations.