Wednesday, July 20, 2011

GREGOR MENDEL

TODAY WE CELEBRATE THE 189TH BIRTHDAY OF THIS GREAT SCIENTIST. FOR THOSE OF YOU WHO DO NOT KNOW ABOUT HIM, I HAVE INSERTED THE FOLLOWING INFORMATION:

Gregor Mendel, who is known as the "father of modern genetics", was inspired by both his professors at the University of Olomouc (i.e. Friedrich Franz & Johann Karl Nestler) and his colleagues at the monastery (i.e. Franz Diebl) to study variation in plants, and he conducted his study in the monastery's two hectare experimental garden, which was originally planted by the abbot Napp in 1830. Between 1856 and 1863 Mendel cultivated and tested some 29,000 pea plants (i.e., Pisum sativum). This study showed that one in four pea plants had purebred recessive alleles, two out of four were hybrid and one out of four were purebred dominant. His experiments led him to make two generalizations, the Law of Segregation and the Law of Independent Assortment, which later became known as Mendel's Laws of Inheritance.
Mendel did read his paper, Versuche über Pflanzenhybriden (Experiments on Plant Hybridization), at two meetings of the Natural History Society of Brünn in Moravia in 1865. It was received favorably and generated reports in several local newspapers. When Mendel's paper was published in 1866 in Verhandlungen des naturforschenden Vereins Brünn, it was seen as essentially about hybridization rather than inheritance and had little impact and was cited about three times over the next thirty-five years. (Notably, Charles Darwin was unaware of Mendel's paper, according to Jacob Bronowski's The Ascent of Man.) His paper was criticized at the time, but is now considered a seminal work.

After Mendel completed his work with peas, he turned to experimenting with honeybees, in order to extend his work to animals. He produced a hybrid strain (so vicious they were destroyed), but failed to generate a clear picture of their heredity because of the difficulties in controlling mating behaviours of queen bees. He also described novel plant species, and these are denoted with the botanical author abbreviation "Mendel".
After he was elevated as abbot in 1868, his scientific work largely ended, as Mendel became consumed with his increased administrative responsibilities, especially a dispute with the civil government over their attempt to impose special taxes on religious institutions. At first Mendel's work was rejected, and it was not widely accepted until after he died. At that time most biologists held the idea of blending inheritance, and Charles Darwin's efforts to explain inheritance through a theory of pangenesis were unsuccessful. Mendel's ideas were rediscovered in the early twentieth century, and in the 1930s and 1940s the modern synthesis combined Mendelian genetics with Darwin's theory of natural selection.
Mendel died on January 6, 1884, at age 61, in Brno, Moravia, Austria-Hungary (now Czech Republic), from chronic nephritis. Czech composer Leoš Janáček played the organ at his funeral. After his death, the succeeding abbot burned all papers in Mendel's collection, to mark an end to the disputes over taxation.