Along with Harry Creighton, she demonstrated the physical basis for  crossing over, though she is far more famous for discovering transposons.
After her PhD in botany from Cornell, she moved to the University of Missouri before settling at Cold Spring Harbor Lab. While there, she studied mosaicism in the coloration of maize kernels and identified the genetic loci Dissociator  (Ds) and Activator (Ac). However, by 1953, she stopped publishing papers regarding these ―controlling elements‖ due to  rejection of the concept by her fellow geneticists. Along with Harry Creighton, she demonstrated the physical basis for  crossing over, though she is far more famous for discovering transposons. FTP, name this winner of the 1983 Nobel  Prize in Physiology of Medicine.
After her PhD in botany from Cornell, she moved to the University of Missouri before settling at Cold Spring Harbor Lab.
Barbara McClintock