Carl Correns(1864 — 1933)

In 1900, Carl Correns published his results on the heredity of peas and maize, unaware that two other botanists, Hugo de Vries and Erich von Tschermak, were making the same discovery at almost exactly the same moment. While reviewing the scientific literature, he came across Gregor Mendel's forgotten 1865 paper and realized that the Moravian monk had discovered it all thirty-five years earlier.

Correns had a strong personal connection to Mendel: his professor Carl von Nägeli, in Munich, had corresponded with Mendel during his lifetime but had never grasped the importance of his work. Correns thus indirectly inherited this story and became one of the first to do justice to the forgotten monk.

Rather than claiming the glory for himself alone, Correns honestly stressed Mendel's priority and called these principles the “laws of Mendel.” This act of scientific recognition has remained an example of intellectual honesty in the history of science.

Correns studied heredity in the four o'clock flower (Mirabilis jalapa) and discovered that certain traits, such as the color of variegated leaves, were not transmitted according to Mendel's laws but only through the mother. He thus revealed “extranuclear heredity,” a mode of transmission that does not pass through the cell's nucleus.

At his death in 1933, much of his notes and unpublished research was kept in Berlin, but many of his manuscripts were destroyed during the bombings of the Second World War, erasing part of the work of this quiet pioneer of genetics.