Ian is best known for global-scale analysis of plant traits, for careful quantification of plant structure-function relationships, and for using concepts from microeconomics to understand plant ecology and evolution (e.g. “Leaf Economic Spectrum”; “Least-cost theory”).

New work as a Chief Investigator with the ARC Centre for Plant Success in Nature & Agriculture focuses on understanding adaptations to heat and water stress within the Australian flora, including in crop wild relatives.