Johann Mendel was born on July 22, 1822 in Hyncice, Silesia, the Hapsburg Empire, Austria. His mother was Rosine and his father, Anton. He had two elder sisters, Veronica and Theresia.

When he was old enough, Johann went to the local school. His teachers soon realized his brilliance, and recommended him to a higher-level school, the Gymnasium, which was 36 kilometers from his home. The Mendels were poor, but they managed to scrape up some money for his tuition. He spent six years there, and graduated in 1840.

Johann wanted to continue his education, but his father was seriously injured by a falling tree, and wanted him to take over the farm for a while. Luckily, his sister Veronica had been married while he was at school, and her husband offered to take the farm for a while. His other sister, Theresia, offered him part of her dowry money so he could go to University. In turn, he agreed to put her children all the way through school.

In 1841, Johann started classes at the Philosophy Institute of Olomouc. He studied there for two years and then he was recommended to the St. Thomas Monastery by one of his teachers. The head of the monastery, Abbot Napp, decided he was worth of becoming a monk, and welcomed him. He entered the monastery in 1843, at 21 years of age. As the tradition goes, he assumed a new name, Gregor.

Every morning, Gregor got up at six o’clock and went straight to the library to study. He studied theology, physiology, and natural sciences. He also taught 20 Latin, Greek, and mathematics classes a week to students at the monastery school. In 1850, Mendel took the exam necessary to become a certified teacher. He failed it, and was told to come back the next year and retake it. Abbot Napp sent him to the University of Vienna to learn more so he could pass his exam next time. He studied there for two years. Then, in 1855 he retook his exam, but fell ill and was unable to complete it.

The first experiments Mendel conducted used mice. He was interested in the inheritance of the color of the mice’s coats. He bred them until Abbot Napp suggested that maybe watching mice mate wasn’t the best task for a religious monk. So Mendel began studying plants.

Mendel chose the common garden pea, of the genus Pisum, to experiment on. First he chose seven characteristics to look at: the position of the flowers on the stem, the stem length, the color of the unripe pod, the shape of the ripe seed, the color of the seed coat, the shape of the ripe pod, and the color of the ripe seed. Then he planted his first generation of peas and watched them grow. For two years he kept planting the seeds to make sure they were pure breeding, that is, they always produced offspring that had the same characteristics as their parent plants. Then he began his experiments.

The first of the experiments that he conducted crossed plants with round seeds and plants with wrinkled seeds. The resulting plants produced all round seeds! The next year he grew plants from these round seeds and allowed them to self-fertilize and produce more seeds. This time there were 5474 round seeds and 1850 wrinkled seeds, making a 3:1 ratio of round to wrinkled seeds.

Mendel was fascinated! It seemed that the wrinkled trait, which seemed to disappeared in the first generation of offspring, reappeared in the second generation. He called the round trait "dominating" and the wrinkled trait "recessive."

Mendel was the first person to use a single letter to represent each trait, with a capital letter (A) to represent the dominant trait and a lowercase letter (a) to represent the recessive trait. When two pure-breeding parent plants were crossed, their hybrid offspring were represented as Aa. For every four peas produced in the second generation of offspring (when the hybrids, represented by Aa, were allowed to self-fertilize), one pea could be called A (pure dominant round), two peas could be called Aa (round but also carrying the potential to produce wrinkled peas), and one pea could be called a (pure recessive wrinkled).

Mendel repeated the experiment with the other six characteristics and got the same 3:1 ratios. He also tried crosses considering two different characteristics at the same time. For example, he crossed plants producing round yellow peas with plants producing green wrinkled peas. Finally, he did backcrosses, in which first generation hybrids were crossed with either pure-breeding dominants or pure-breeding recessives.

By 1863, Mendel’s experiments with peas were finally complete. He didn’t know about the existence of genes or chromosomes, but he knew that every plant had two factors that determined its appearance for a particular characteristic, one inherited from each parent. He learned that these factors could be dominant or recessive, and that when a plant inherited both a dominant and a recessive factor, the recessive factor was masked but could reappear in a later generation.

On March 30, 1863, Abbot Napp died and Mendel was elected to be the new abbot. He didn’t have as much time for his plants, but he did conduct some experiments using beans, snapdragons, sweet William and maize to confirm the results he had obtained with peas. In 1865 Mendel gave two lectures about his experiments, but he used formulas no one understood, and confused his audience. His results were published the following year but few people seem to have read them. His work was forgotten for the next 30 years.

On October 13, 1870, a tornado raged through Brunn. Mendel observed it through his open window, taking notes. Afterwards, he went to look at the damage, and found that the tornado had destroyed the greenhouse. He was devastated. He began to breed bees in his spare time, crossing bees from Egypt and bees from South America. He started smoking cigars to lose weight, but it didn’t work. Then on January 6^th, 1884, at 2 o’clock in the morning, he died of kidney failure.

In 1900 three biologists, Carl Correns, Hugo de Vries, and Erich Tschermak, working independently, rediscovered Mendel’s principles of inheritance. They were dismayed to find that a mere monk, who had died 15 years earlier, had already published their discoveries. Today Mendel’s work is world-renowned and has inspired generations of modern geneticists. In my opinion, he is truly the Father of Genetics.

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