Johann Karl Nestler, Jan Karel Nestler (16 December 1783 – 9 July 1842) was an Austrian scientist in the field of hereditary traits, professor of natural history and agriculture at the Philosophical Faculty of University of Olomouc, dean of the faculty and rector of the university, and doyen of the Czech agriculture science. Nestler studied philosophy, theology and law in years 1800–06 at the Olomouc Academical Lyceum (the University of Olomouc was degraded to academical lyceum in 1782–1826). Then in years 1806–12 he was an educator in Althart / Staré Hobzí and in years 1812–18 he was a director of a high school in Klafterbrunn, Lower Austria. In years 1818–20 he received technical education in agriculture. He studied agriculture at the University of Vienna in years 1820–21, where he later also worked as adjunct at the Department of Agriculture. In year 1823 Nestler became the professor of agriculture, and in 1824 also of natural history, at the Academy of Nobility and at the academical lyceum in Olomouc. After the lyceum was restored to University status, Nestler obtained Doctorate of Philosophy. In 1835 he became the rector of the University and in 1837 he became the dean of its Faculty of Philosophy. right During his teaching Nestler included a special section dealing with scientific animal and plant breeding. His main emphasis was on sheep breeding to improve wool protection for the benefit of the textile industry. In his published lectures Nestler (1829) encouraged sheep breeders to elaborate the theoretical basis of the selection process. Nestler also tried to explain how nature produces new species of animals and plants through forces beyond the hand of man and how breeders control the reproductive process and use modifications, such as inbreeding or outcrossing, for increased production. Through the examination of the registers of the best stock animals and their offspring Nestler hoped to explain the Vererbungsgeschichte (genetic history).