Graves, Jennifer Ann Marshall (1941-…), is an Australian molecular geneticist known for her research on chromosomes. Chromosomes are the tiny, thin, threadlike structures found in cells of all organisms. Chromosomes are the carriers of inheritance—that is, the physical or behavioral characteristics offspring receive from parents. Chromosomes consist mostly of genes, the basic unit of heredity.
In her research, Graves studied the chromosomes and genes of many animals native to Australia. These include the egg-laying platypus and marsupials such as kangaroos and Tasmanian devils. A marsupial is a mammal whose young are born in an extremely immature state. Graves also studied the chromosomes of reptiles, including the bearded dragon, a kind of lizard. By studying and comparing a variety of animals, Graves investigated how genes, chromosomes, and the body systems they regulate work and how they evolved over time.
Among other topics, Graves has investigated the origin and function of the chromosomes that determine sex in mammals. Human beings and many other mammals normally have two sex chromosomes, with females having two X chromosomes (typically written XX) and males having one X and one Y chromosome (XY). By comparing the chromosomes of Australian platypuses, marsupials, and more advanced mammals, Graves determined that this XY system of sex chromosomes had evolved relatively recently among mammals. Based on her findings, Graves has famously suggested that the human Y chromosome will eventually disappear in future generations.
Jennifer Ann Marshall was born on Nov. 24, 1941, in Adelaide, in the Australian state of South Australia. She studied at Adelaide University, where she earned a bachelor’s degree in 1964 and a master’s degree in 1967. She continued her education in the United States at the University of California at Berkeley, where she received her Ph.D. degree in 1971. In the United States, she met John Graves, whom she married. From 1971 to 2001, she worked at La Trobe University in Melbourne, Australia. She then joined the faculty at Australia National University in Canberra. She has published several books and more than 400 scientific papers over her career. In 2010, Graves was named an Officer of the Order of Australia. The Order of Australia is Australia’s highest award for service to the country or to humanity. In 2017, Graves was awarded the Prime Minister’s Prize for Science, Australia’s highest science award. In 2022, she was made a Commander of the Order of Australia, a higher level in the Order, “for eminent service to science, particularly through leadership and research in evolutionary genetics.”
