41. Mary-Claire King
Dates: February 27, 1946 -
Known for: A researcher studying genetics and breast cancer, King is also noted for the then-surprising conclusion that humans and chimpanzees are quite closely related. She used genetic testing in the 1980s to reunite children with their families after a civil war in Argentina.
42. Nicole King
Dates: 1970 -
Known for: Nicole King studies the evolution of multicellular organisms, including the contribution of one-celled organisms (choanoflagellates), stimulated by bacteria, to that evolution.
Dates: January 15, 1850 - February 10, 1891
Known for: Sofia Kovalevskaya, mathematician and novelist, was the first woman to hold a university chair in modern Europe and the first woman on the editorial staff of a mathematical journal.
44. Mary Leakey
Dates: February 6, 1913 - December 9, 1996
Known for: Mary Leakey studied early humans and hominids at Olduvai Gorge and Laetoli in East Africa. Some of her discoveries were originally credited to her husband and co-worker, Louis Leakey. Her discovery of footprints in 1976 confirmed that australopithecines walked on two feet 3.75 million years ago.
45. Ada Lovelace
(Augusta Ada Byron, Countess of Lovelace)
Dates: December 10, 1815 - November 27, 1852
Known for: Ada Lovelace created the concept of an operating system or software.
46. Wangari Maathai
Dates: April 1, 1940 - September 25, 2011
Known for: Founder of the Green Belt movement in Kenya, Wangari Maathai was the first woman in central or eastern Africa to earn a Ph.D., and the first woman head of a university department in Kenya. She was also the first African woman to win the Nobel Peace Prize.
47. Lynn Margulis
Dates: March 15, 1938 - November 22, 2011
Known for: researching DNA inheritance through mitochondria and chloroplasts, and originating the endosymbiotic theory of cells, showing how cells cooperate in the process of adaptation. Lynn Margulis was married to Carl Sagan, with whom she had two sons. Her second marriage was to Thomas Margulis, a crystallographer, with whom she had a daughter and a son.
48. Mary the Jewess
Dates: probably first century C.E.
Known for: Known through surviving fragments of her writing, only a few of the texts that she is reputed to have originated, Maria or Mary the Jewess worked in Alexandria as an alchemist, experimenting with distillation, inventing a device called the tribokos and a process and device both called the kerotakis. "Mary's Black" refers to black sulfide produced using the process of kerotakis. A process of cooking with a water-bath called, in French, bain marie, is also named for Mary the Jewess who described the technique.
Dates: June 16, 1902 - September 2, 1992
Known for: Geneticist Barbara McClintock won the 1983 Nobel Prize in medicine or physiology for her discovery of transposable genes.
50. Margaret Mead
Known for: Anthropologist Margaret Mead, a curator of ethnology at the American Museum of Natural History from 1928 to her retirement in 1969, published her famous Coming of Age in Samoa in 1928, receiving her Ph.D. from Columbia in 1929. The book, which claimed that girls and boys in the Samoan culture were both taught to and allowed to value their sexuality, was something of a sensation. It has recently been criticized for naivete, most notably by Derek Freeman, summarized in his book, Margaret Mead and Samoa: The Making and Unmaking of an Anthropological Myth (1983).