Deborah Charlesworth is a population geneticist who works on the evolution of mating systems in plants. She has particularly focused on selection acting on traits that help plants to avoid inbreeding, and on the comparatively recent evolution of separate males and females — dioecy — in the plant kingdom.

To study dioecy and compare its genetic basis with that of hermaphrodite species, Deborah introduced the White Campion as a model system. She has also explored how many hermaphrodite species reject their own pollen in order to avoid the danger of inbreeding depression, the reduction in fitness in the offspring of closely related individuals.

Although well into retirement, Deborah has continued her research, applying next-generation sequencing to search for evidence of genetic recombination and the accumulation of deleterious mutations. With her husband, Fellow Brian Charlesworth, she is the author of the definitive textbook Elements of Evolutionary Genetics (2010), and received the Molecular Ecology prize in 2011.