Lynn Margulis (1938–2011), American biologist Deborah Martin-Downs, Canadian aquatic biologist, ecologist Sara Branham Matthews (1888–1962), American microbiologist Barbara McClintock (1902–1992), American geneticist, Nobel prize for Physiology or Medicine 1983 Eileen McCracken (1920–1988), Irish botanist Ruth Colvin Starrett McGuire (1893–1950), American plant pathologist Anne McLaren (1927–2007), British developmental biologist Ethel Irene McLennan (1891–1983), Australian botanist Eunice Thomas Miner, American biologist, executive director of the New York Academy of Sciences 1939–1967 Rita Levi-Montalcini (1909–2012), Italian neurologist (Nobel prize for Physiology or Medicine 1986 for growth factors)