Ruth Geyer Shaw (born 1953) is a professor and principal investigator in the Department of Ecology, Evolution and Behavior at the University of Minnesota. She studies the processes involved in genetic variation, specializing in plant population biology and evolutionary quantitative genetics. Her work is particularly relevant in studying the effects of stressors such as climate instability and population fragmentation on evolutionary change in populations. She has developed and applied new statistical methods for her field and is considered a leading population geneticist.