Mary Calderone (July 1, 1904) was an American physician, public health advocate, and founder of Planned Parenthood. She is best remembered for overturning the American Medical Association policy against disseminating birth control information to patients. She co-founded the Sex Information Education Council of the United States and served as director of Planned Parenthood. She wrote many books that promote sex education and become and advocate for legalized abortion.

Selman Waksman (July 2, 1888) was a biochemist and microbiologist. He specialized in soil microbiology and set to systematically search for antibiotics produced by soil microbes. This led him to discover streptomycin for which he earned the 1952 Nobel Prize for Physiology or Medicine. He also discovered several antibiotics, from the soil bacterium actinomycetes, valuable for killing Gram positive bacteria like the bacillus Mycobacterium tuberculosis and the Gram negative bacteria like Vibrio cholerae and Salmonella typhi. He establish the Waksman Foundation for Microbiology and was the director of the institute of Microbiology at Rutgers University, his most influential book was Principles of Soil Microbiology.

Ernst Mayr (July 5, 1904) was a world leading evolutionary biologist. His earlier work on speciation and founder populations was very instrumental in the development of the modern synthetic theory of evolution. This theory brings together the work of Charles Darwin and Gregor Mendel, including the mechanism of gene mutations, recombination, chromosome structure/function, and natural selection. His work on reproductive isolation led him to propose a definition of species that is currently used. He wrote many books; among them his seminal work on the modern theory of evolution is explained in his book, Systematics and the Origin of Species.

Rosalyn Sussman (July 19, 1921) was an American Physicist that developed radioimmunoassay techniques for which she received the 1977 Nobel Prize for Physiology or Medicine. Radioimmunoassay is use to screen minute amounts of biological substances in body fluids. For example RIA is used to detect the hepatitis viruses and other substances in blood banks; and to calibrate the effective amount of drugs and antibiotics. She lectured in physics and became the assistant chief nuclear physicist in the radioisotope service at the Veteran Administration Hospital.

Gregor Mendel (July 22, 1822) was a botanist, Augustinian prelate and a geneticist who proposed the laws of heredity. Mendel is considered the father of genetics because his experiments revealed that inheritance of traits or characteristic are passed form one generation to the next as discrete units, later called genes. This falsify the widely believe idea that inheritance happened by the blending of the parents’ characteristics. Mendel found two Laws that control how simple traits are inherited; simple traits are those that depend on the expression of one gene only. Mendel’s work was the start of genetics; scientists following on Mendel’s footsteps extended his ideas to complex traits, those depending on the expression of two or more genes.

Carl Jung (July 26, 1875) was a Swiss psychologist who invented analytical psychology. Jungian psychology in some aspects is a response to Freud psychoanalysis. He proposed the idea of extraverted and introverted personalities as well as the existence of collective unconscious. Earlier in his career Jung and Freud collaborated and corresponded frequently, later Jung developed different ideas that lead to the divergence and break between them. He wrote several books and is consider one of the fathers of psychology.