Mendel , Gregor Johann

(1822–1884) Austrian plant geneticist

Born in Heinzendorf (now Hynčice in the Czech Republic), Mendel studied at Olmütz University before entering the Augustinian monastery at Brünn (now Brno in the Czech Republic) in 1843. His childhood experience of horticultural work as the son of a peasant farmer had given him an interest in the role of hybrids in evolution, and in 1856 he began plant-breeding experiments. He studied seven characters in pea plants and obtained important results after much laborious recording of character ratios in the progeny of crosses. From his experiments Mendel concluded that each of the characters he studied was determined by two factors of inheritance (one from each parent) and that each gamete (egg or sperm cell) of the organism contained only one factor of each pair. Furthermore he deduced that assortment into gametes of the factors for one character occurred independently of that for the factors of any other pair. Mendel's results are summarized today in his law of segregation and law of independent assortment (Mendel's laws).

Mendel's work is now recognized as providing the first mathematical basis to genetics but in its day it stimulated little interest. He read a brief account of his research to the Brünn Natural History Society in 1865 and asked members to extend his methods to other species, but none did. In 1866 he published his work in the society's Verhandlungen (Proceedings), a journal distributed to 134 scientific institutions, and sent reprints of the paper to hybridization ‘experts’ of the time. Karl Naegeli, the Swiss botanist, was skeptical of his results and suggested that he continue work on the hawkweeds (Hieracium), a genus now known to show reproductive irregularities and with which Mendel was bound to fail.

Mendel's work with peas, and later with Matthiola, Zea, andMirabilis, had shown that characters do not blend on crossing but retain their identity, thus providing an answer to the weakness in Charles Darwin's theory of natural selection. Mendel read a copy of Darwin's Origin of Species, but unfortunately, Darwin never heard of Mendel's work.

Mendel became abbot of the monastery in 1868 and thereafter found less time to devote to his research. It was not until 1900, when Hugo de Vries, Karl Correns, and Erich von Tschermak came across his work, that its true value was realized.