Louis Leakey (October 7, 1903) was a Kenyan archaeologist, naturalist, and paleoanthropologist that greatly contributed on the study of early human evolution. Perhaps the most important discovery was made by his wife Mary in Olduvai Gorge, Tanzania, where she found a hominid skull and identified it as belonging to the genus Homo. Leakey called it Homo habilis (handy man) because the remains where associated with several stone tools. He proposed that Homo habilis was a direct ancestor of modern humans, Homo sapiens, and that it lived at the same time as the Australophitecus. This proposal was controversial at the beginning but the finding of additional fossils by the Leakey team and others confirmed that Homo habilis was evolutionary in between Australopitecus and Homo erectus, at the time believed to be an ancestor of Homo sapiens. There were others fossil found by Mary and the team like Zinjanthropus (1.7 million years old), Kenyapithecus (14 million years old), and Proconsul africanus (25 million years old). Leakey’s findings demonstrated that human evolution happened in Africa and not in Asia. He wrote several books and was the curator at the museum of Nairobi.

Mae Jemison (October 17, 1956) is an American physician, a chemical engineer, and an astronaut. After practicing medicine in California, she became a medical officer for Peace Corps in Liberia and Sierra Leone in West Africa. Jemison was involved in biological research projects like the development of a vaccine for hepatitis B, schistosomaisis, and rabies. During this time she was active in training volunteer personal in public health and safety issues. After returning to the USA she was accepted to become a NASA astronaut. In 1992, Jemison orbited Earth for nearly a week in the space shuttle Endeavor as a science mission specialist. She worked in a USA and Japan mission to study material processing were she was a co-investigator into bone cell research experiments in space. After she left NASA, Jemison taught at Dartmouth and established the Jemison group for research into advance technologies.

John Dewey (October 20, 1859) was an American philosopher, an educator and a psychologist. He co-founded the philosophical movement called ‘pragmatism’. Dewey thought that human experiences are the result of the interaction among ever-changing processes and human endeavors, and that secret to a happy life is to learn how to live with these dynamic processes. His studies on experimental psychology and child psychology prompted him to develop a philosophy of education. Dewey wrote several books, articles, and periodicals including his most influential book in education, ‘Experience & Education’ (1938). Dewey proposed that human knowledge is tied to changing and challenging experiences. These changes through time became a history with an outcome. This history can be identified and influenced, by targeting at the experiences. When these ideas are applied to education, educators can be the agents that adjust the conditions or experiences to allow children’s growth. Dewey’s ideas on constructivism, inquiry, logic, and the use of past experiences in learning have been very influential in education.

George Beadle (October 22, 1903) was an American geneticist. He shared the Nobel Prize on Physiology or Medicine in 1958 with Tatum and Lederberg for work on demonstrating that one structural gene can be linked to a specific biochemical function. Beadle became interesting in how genes affect the actual chemistry of the cell and wanted to find the link between DNA and the function of proteins. After starting work in the fruit fly, Drosophila melanogaster, and finding that the fly’s eye color is due to a series of chemical reactions that somehow were controlled by genes, he move to research these questions in a simpler organism, the red bread mold Neurospora. He used X-rays to produce DNA mutations and inactivate genes, from the study of these mutants, he showed that each gene codes for one specific enzyme and propose the idea of ‘one gene one protein’. Beadle wrote many books and became the president of the University of Chicago.

Anthony van Leeuwenhoek (October 24, 1632) was a Dutch merchant and a scientist; he started as a textile merchant using magnifying glasses to count the threads in the textiles as a quality control practice. Van Leeuwenhoek made high quality lens as a hobby, it was perhaps his natural curiosity and creativity that made him direct his observations to the microscopic natural world. He set to develop and make several types of microscopes to help him observe microorganisms. His first observations of ‘animalcules’ include protozoa and he was the first person that ever observed and reported that water contains bacteria. Later observations include red blood cells, nematodes, crystals, and sperm. This led him to suggest that fertilization happens when spermatozoa enters the egg. His studies on the life history of several organisms like the flea, ants, mussels, and eels showed that, in opposition to popular belief,  lower animals are not produced spontaneously. Van Leeuwenhoek is remembered as the father of microbiology and for the beautiful drawings of his animalcules.