James Dewey Watson is an American molecular biologist, geneticist and zoologist. He is credited for co-discovering the molecular structure of deoxyribonucleic acid (DNA), a substance that is the basis of heredity. His discovery has been described by other biologists and Nobel laureates as the most important scientific discovery of the 20th century. He was born in Illinois to James D. Watson and Jean Mitchell. Growing up, James Dewey Watson spent hours bird-watching and decided to major in ornithology but Erwin Schrodinger’s book titled ‘What is Life’ had such a profound impact on him that he chose genetics in the end. He received his B.S. degree from the University of Chicago, and his PhD from Indiana University. He was strongly opposed to the belief that genes were proteins that could replicate and DNA was a simple tetranucleotide that supported the genes. James’ perception, influenced by the discoveries and lectures of that time, was that DNA was indeed the genetic molecule. He finally found success with Francis Crick and Maurice Wilkins, when the trio discovered the double helix structure of the DNA molecule. For this discovery James Dewey Watson, Francis Crick and Maurice Wilkins earned the Nobel Prize for Physiology or Medicine in 1962