Ernest Everett Just was a leading American biologist of African-American origin. He made significant contributions to the fields of invertebrate zoology and embryology. In his research, he tried his best to simulate a natural environment for the study of whole cells instead of breaking them down in laboratory conditions. As he emphasized that the conditions in the laboratory should be closest to the natural environment, he is regarded as one of the pioneers among the ecological developmental biologists. His work on experimental parthenogenesis has played a vital role in the growth of modern evolutionary and developmental biology.