Gregor J. Mendel

He carries out numerous crossing experiments on pea plants in the monastery garden of the Brno Abbey of St. Thomas and describes the inheritance of various characteristics. The results, now known as Mendel's rules of inheritance, were published in 1866 but fell into obscurity. Image: photographer and date unknown (William Bateson: Mendel's Principles of Heredity. A Defence. London 1902. Online: https://commons.wikimedia.org/wiki/File:Gregor_Mendel_Monk.jpg)