James Watson and Francis Crick
James D Watson and Francis Crick on April 2, 1953, proposed that DNA was a double-helix structure, not a triple stranded structure as had been previously thought. The discovery in 1953 of the double helix, the twisted-ladder structure of DNA, by James Watson and Francis Crick marked a milestone in the history of science. Watson and Crick made their proposal based on the research of many other scientists and credited those pioneers respectfully. Such research included the crucial X-ray image “Photo 51" from Rosalind Franklin in 1952, as well as her more clarified DNA image with Raymond Gosling, Maurice Wilkins, Alexander Stokes, and Herbert Wilson and base-pairing chemical and biochemical information by Erwin Chargaff.