British naturalist.

• Independently devised a theory of natural selection

Dutch naturalist.

• Known for his studies of microorganisms through early microscopes

German bacteriologist.

• Invented a test for syphilis

British naturalist who developed a theory of evolution based on his observations of flora and fauna in South America.

• Wrote On the Origin of Species by Means of Natural Selection

German biologist and philosopher.

• Advocate of evolution who believed that during gestation each animal passes through the stages of its species'' evolution

American, born a slave, who became a leading agronomist and agricultural chemist.

• Known for research on uses of the peanut

Austrian monk and botanist; one of the founders of modern genetics.

• Conducted breeding experiments and made observations on inheritance now codified as Mendel''s Law

British biologist.

• Linked Marxist philosophy and the theory of evolution

French naturalist.

• Developed an early theory of evolution based on the inheritance of adaptive modifications made during an animal''s lifetime

British biologist.

• Known for his popular books on biology

American horticulturalist.

• Known for his work on the cultivation and study of plant life without the use of scientific experimentation and chemicals

German-American biologist.

• Noted for his pioneering work in modern molecular genetics

German pathologist and statesman.

• Founder of cellular pathology

Indian physicist and botanist.

• Invented the crescograph, an instrument for studying the growth of plants

English biologist, philosopher and educator.

• Prominent supporter of Darwin''s theory of evolution

American medical researcher.

• First female professor at Johns Hopkins; first woman elected to life membership in the National Academy of Sciences

• Co-discovered the first antibiotic effective against fungus

Biochemist and educator.

• Isolated vitamin E from wheat germ

American biologist.

• Known for her studies of parthenogenesis, hermaphroditism, and the life cycle of insects

American microbiologist.

• Known for her classification of streptococcal bacteria

American biologist, environmentalist and writer. Her books were among the first to draw attention to human environmental devastation.

• Author of books that encouraged environmental conservation, most notably Silent Spring

American zoologist and conservationist. Murdered, perhaps by poachers.

• Led a long-term study of mountain gorillas in the Virunga mountains of Rwanda; wrote Gorillas in the Mist

British ethnologist.

• Her observations of chimpanzees have greatly expanded scientific and popular understanding of the higher primates

American zoologist and physiologist.

• First female researcher at the Harvard Medical School

American biologist.

• Known for her work on the role of the X chromosome

American physiologist known for her work on cell growth and division.

• In 1983, received a National Science Foundation Lifetime Achievement Award for her contributions to the advancement of women and underrepresented minorities

American plant biologist.

• President of the Association for Women in Science

British biophysicist.

• Her X-ray studies of DNA paved the way for Watson & Crick''s discovery of its double-helix structure

American embryologist.

• Known for her studies of the heredity of certain types of cancers

Canadian geneticist.

• An expert on Down Syndrome and other chromosomal irregularities

American geneticist who helped develope a test for Huntington's Disease.

• President of the Hereditary Disease Foundation, 1969-

Chinese-born American bacteriologist.

• Co-discoverer of HIV, the virus that causes AIDS

Canadian anthropologist.

• The world''s foremost authority on the orangutan