Professor and Chair, Biology Department
Hilary Callahan's integrative research examines many different features of plants — from roots to flowers to seeds. She seeks to understand how plant traits function in nature, including how external factors affect trait expression and how rapidly traits evolve. To link plant traits with plant genes, she frequently works with the genomic model Arabidopsis thaliana — the "fruit fly of botany." Her interest in how multiple traits are integrated usesArabidopsis as well as longer-lived shrubs and trees growing in Barnard's greenhouse, at nearby botanical gardens, and at several experimental forests in the northeastern region. Her expertise is relevant to understanding how plant traits may change in response to anthropogenic global change. She receives funding from the National Science Foundation, and many of her students' research projects have been supported by Barnard's Hughes Science Pipeline Project. She teaches courses in Plant Evolution and Diversity, Applied Ecology and Evolution, Global Change Ecology, and Evolutionary Genetics. She oversees the living collections of the Arthur Ross Greenhouse on the roof of Milbank Hall and serves as an affiliated faculty member of Columbia's Department of Ecology, Evolution and Environmental Biology.
"Constraints on the evolution of phenotypic plasticity: limits and costs of plasticity" (with C.J. Murren and a large working group), Heredity (2015)
"Experimentally limiting root-microbe interactions reveals limited plasticity in functional root traits" (with M.H. Lee and L.H. Comas), Annals of Botany. 113 (2014)
"Symposium Report: Advancing our understanding of plant-fungal symbioses" (with L.H. Comas and A. Tuininga) New Phytologist 185 (2010)
"Impacts of elevated nitrogran inputs on oak reproductive and seed ecology" (with K. del Fierro, A.E. Patterson, H. Zafar), Global Change Biology 14 (2008)
"Plasticity genes and plasticity costs: a new approach using Arabidopsis recombinant inbred populations" (with M.C. Ungerer), New Phytologist 166 (2005)
"Shade-Induced Plasticity and Its Ecological Significance in Wild Populations of Arabidopsis Thaliana" (with M. Pigliucci), Ecology 83 (2002)
"Phenotypic Integration and the Plasticity of Integration in an Amphicarpic Annual" (with D. M. Waller), Internat. J. of Plant Sciences 161 (2000)
"Developmental Phenotypic Plasticity: Where Ecology and Evolution Meet Molecular Biology" (with M. Pigliucci, and C. D. Schlichting), Bioessays 19 (1997)
Plant ecological genetics, evolution of plant phenotypes and plant genomes, societal relevance of plant genetic diversity
In the News
On April 22, the planet had two reasons to celebrate: It was Earth Day and science was on most people’s minds.
Three faculty members will participate in Barnard's Sixth Annual Global Symposium "Women Changing China."
Food for Thought from Faculty Experts
Environmental science and biology field work on an urban rooftop