What is Carl Correns?
[[Image:Carl Correns.jpg|thumb|Carl Correns]] '''Carl Erich Correns''' (10 September 1864 – 14 February 1933) was a [[Germany|German]] [[botanist]] and [[genetics|geneticist]]. His research into [[heredity]] led to his rediscovery of [[Gregor Mendel]]'s earlier work. [[Hugo de Vries]] also – independently – rediscovered [[Gregor Mendel]]'s work on [[genetics]]. [[Erich von Tschermak]]'s status as a third rediscoverer is now less convincing. Correns grew hybrids of [[pea]]s, and of [[maize]], and reached the same interpretation as Mendel, in 1899.<ref>Correns C. 1900. G. Mendels Regel über das Verhalten der Nachkommenschaft der Rassenbastarde. ''Ber. deutsch. botan. Zeit''. '''60''', II, 5/6:65–82</ref> The occurrence of cases in which the [[heterozygote]] is intermediate (the absence of [[Allele|dominance]]) was added in a footnote to his 1900 paper. That dominance was not always present had been seen and understood by Mendel, according to his letters to [[Karl Wilhelm von Nägeli|Nägeli]].<ref>Sturtevant A.H. 1965. ''A history of genetics''. Harper & Row N.Y. p31</ref> By a quirk of history Correns was a student of Nägeli, a renowned botanist with whom Mendel corresponded about his work with peas. Nägeli failed to understand how significant Mendel's work was. In 1913 Correns became the first director of the newly founded [[Wilhelm II of Germany|Kaiser Wilhelm]] Institute for Biology in [[Berlin]]-Dahlem. == Later work == Correns produced the first evidence of [[cytoplasm]]ic inheritance, in his 1909 paper on variegated leaf colour in ''Mirabilis jalapa''.<ref>Correns C. Vererbungsversuche mit blass (gelb) grünen und buntblättrigen Sippen bei Mirabilis, Urtica, und Lunaria. Zeits. ind. Abst. Vererb. 1:291–329</ref> The basis of this inheritance is that [[chloroplast]]s, the [[organelle]]s which conduct [[photosynthesis]], are inherited solely from the maternal parent.<ref>{{cite journal | quote = yes |last=Hagemann |first=R |year=2000 |title=Erwin Baur or Carl Correns: who really created the theory of plast