History of genetics of the fruit fly "Drosophila melanogaster". In 1928, Frederick Griffith showed that genes could be transferred. In what is now known as Griffith's experiment, injections into a mouse of a deadly strain of bacteria that had been heat-killed transferred genetic information to a safe strain of the same bacteria, killing the mouse. A series of subsequent discoveries led to the realization decades later that the genetic material is made of DNA (deoxyribonucleic acid). In 1941, George Wells Beadle and Edward Lawrie Tatum showed that mutations in genes caused errors in specific steps in metabolic pathways. This showed that specific genes
What Work Is Fame" and "Growth" are direct accounts of two of Levine's jobs as a young man. "Fear and Fame" is based on a job Levine had cleaning out and refilling acid vats in his mid twenties. "Growth" is about the job Levine held at a soap factory at the age of fourteen. Many of Levine's poems are based on his experience growing up in Detroit. The titular poem, "What Work Is", is based on Levine's experience of waiting in a Detroit employment line. "The Right Cross" is related to a boxing teacher who taught Levine to defend himself while growing up