The Heck brothers and the Aurochs--Give them credit, as they did not have much reference material

Already in 1835, the Polish zoologist Jarocki pleaded in an article to undertake and attempt to get the aurochs back in its original form. But it was still almost hundred year before someone actively began with an attempt to re-breed the aurochs. The brothers Lutz and Heinz Heck have both made attempts to recreate the aurochs in Germany in the 1920s and 1930s. Both brothers did this through cross several cattle breeds, which possessed aurochs characteristics according to them, and to select the offspring. Each brother used his own selection of cattle breeds. Heinz began his experiment in the Hellabrunn Zoo in Munich. Lutz began a bit later than his brother with his experiment in Berlin.