Johann Gregor Mendel was a biologist and ordained priest who conducted experiments in heredity. He used his resources at his monastery to grow thousands of pea plants, keeping detailed records and calculations that debunked the previous theory of “trait blending.” Although people largely didn’t recognize his work during his lifetime, his lengthy research showed that characteristics can be dominant or recessive and are passed on independently. These facts transformed the face of genetics.
Early Life and Education
Mendel was born to Rosine and Anton Mendel on July 22, 1822 in Heinzendorf, Austria, now Hynčice, Czech Republic. At the young age of 11, he and his family moved to Troppau so he could continue his education, and he graduated in 1840. From there, he attended the Philosophical Institute of the University of Olmütz, excelling in math and physics and graduating in 1843.
Following his graduation in Olmütz, he entered the St. Thomas Monastery in Brno, where he had access to a large amount of research materials. Although he was ordained in 1847, due in part to failing health, he temporarily stopped his civil work in the area and went to the University of Vienna. His study there prepared him to go back to the St. Thomas Monastery and take a teaching job at a secondary school. In this setting, he was able to begin the first of his experiments related to genetics.
Pea Plant Experiments
Even though scientists had been investigating inheritance prior to Mendel, many questions were still unanswered. Interested in this field and partly for fun, he decided to experiment using pea plants, because they could be bred quickly, and because so many different kinds were available. Between 1856 and1963, he created thousands of new hybrid plants with different characteristics using cross-pollination techniques. With each new generation of plants, he looked at traits such as seed, cotyledon, flower and pod color, pod shape, flower and pod position and plant height.
Although he didn’t identify genes as they are now known, per se, Mendel used mathematical ratios and detailed records to show that offspring inherit two genes from parents, one from the mother and another from the father. These can be either “dominant” or “recessive,” based on whether the traits to which they relate are expressed. A recessive characteristic does not show up in offspring unless both parents pass on recessive genes, while a dominant one may show up even when just one parent contributes a dominant gene. Mendel summarized these findings and called them the Law of Segregation. He also came up with another concept, the Law of Independent Assortment, which says that allele pairs separate independently during gamete formation and that traits, therefore, get passed on separately from each other.
Confident in his conclusions, in 1865, Mendel wrote about his work under the title Versuche über Pflanzen-Hybride (Experiments on Plant Hybrids) and read the paper twice to the Natural History Society of Brno. He formally published his research in 1866. Despite this, many scientists of the time generally misunderstood his experiments and conclusions or thought the work simply confirmed what people already knew. Mendel did not promote his findings very much past his initial speeches and publication, either, so during his lifetime, people almost ignored what he had accomplished.
It wasn’t until around the turn of the 20th century that individuals began focusing on what he’d discovered. Three European biologists, Erich Tschermak, Hugo de Vries and Carl Correns, found Experiments on Plant Hybrids as they were doing agricultural research. The trio confirmed his findings and, after a priority dispute, conceded that he deserved credit. With this independent verification, his work was finally brought into the spotlight.
Significance of His Work
Mendel’s experiments did away with the previous incorrect idea that the traits an organism has are a mish-mash or blend from the mother or father. They showed that the characteristics living things inherit do not change from one generation to the next, but simply vary in whether they are visible. This discovery created a strong foundation for the field of modern genetics and showed that statistics are important to the field of biology.
Even though he did not fully realize that his conclusions were broadly applicable to the majority of species, scientists that came after him did. They used his studies to begin advanced research not only about general characteristics such as hair color, but to solve puzzles related to inherited diseases. Thanks to him, biology and medical professionals can manipulate what traits appear, a practice increasingly common in agriculture, or even analyze the statistical risk of developing certain conditions.
Later Life
In part because of poor eyesight, Mendel eventually abandoned his scientific pursuits to concentrate on the administrative responsibilities of the abbacy over which he presided. Conflicts related to taxation on monasteries kept him largely isolated within his own monastery and set apart from the public, making it more difficult to be part of the scientific community. He died in Brno on January 6, 1884 at the age of 62 from chronic nephritis, not knowing the long-reaching and long-lasting effects his experiments would have on the scientific and general community. Before his death, however, he said that he believed it would not be long before “the entire world [would] praise the result of [his] labors,” a prediction that took only 16 years after his passing to come true. He is buried in the Brno Central Cemetery.
