Pleiotropy correlations and responses to selection most often exemplify pleiotropy. Pleiotropic traits had been previously recognized in the scientific community but had not been experimented on until Gregor Mendel's 1866 pea plant experiment. Mendel recognized that certain pea plant traits (seed coat color, flower color, and axial spots) seemed to be inherited together; however, their correlation to a single gene has never been proven. The term "pleiotropie" was first coined by Ludwig Plate in his Festschrift, which was published in 1910. He originally defined pleiotropy as occurring when "several characteristics are dependent upon ... [inheritance]; these characteristics will then always appear
Franz Unger of botany at the University of Graz and also taught at the Joanneum (which became the Universalmuseum Joanneum and the Graz University of Technology); in 1850 professor of plant physiology in Vienna. In 1852 he travelled to Northern Europe and to the Orient. Unger retired in 1866 and lived on his farm near Graz. Unger was one of the major contributors to the field of paleontology, later turning to plant physiology and phytotomy. He hypothesized that (then unknown) combinations of simple elements inside a plant cell determine plant heredity and greatly influenced the experiments of his student Gregor Johann Mendel.