TURGOR VERSUS TISSUE: DIFFERENT WAYS TO SUPPORT A LEAF

The systematic distribution and taxonomic utility of leaf venation has been studied for hundreds of years, and the hydraulics of water transport have been measured and modeled for decades, but we still lack a general framework for comparing the ways in which leaves maintain their structural integrity. Here I examine the interplay of two important sources of support: turgor pressure and lignification of skeletal tissue. The differential distribution of these strategies across plant growth form, life history, habitat, and canopy position reveals some obvious patterns, raises questions about cost-benefit approaches to plant function, and suggests traits that may be of paleobotanical relevance for determining otherwise cryptic aspects of past ecosystems.