Gregor Mendel founded genetics after twice failing his teaching exam
An Augustinian friar in Brno grew some 28,000 plants, mostly peas, and found that hidden traits return in predictable ratios. He presented the results to about forty listeners in 1865, and almost nobody understood them. Gregor Mendel's paper was cited roughly three times in 35 years before three botanists rediscovered it in 1900.
Mendel was born Johann in 1822 into a German-speaking farming family in Austrian Silesia, in what is now the Czech Republic. As a boy he gardened and kept bees. His studies were repeatedly interrupted by illness and money trouble, and his younger sister Theresia gave up her dowry to pay for them; he later helped support her sons. He joined the Augustinians at St Thomas's Abbey in Brno partly because the monastery offered an education free of the constant worry about earning a living, and took the name Gregor.
He tried to qualify as a secondary school teacher in 1850 and again in 1856, failing the oral part both times. In between, his abbot sent him to the University of Vienna, where Christian Doppler taught him physics. Back at the abbey he used a two-hectare garden to track seven pea traits, among them seed shape, flower colour and plant height. Crossing a true-breeding yellow-seeded pea with a green one gave only yellow offspring, yet green came back in the next generation in one plant out of four. He called the vanishing trait recessive and the prevailing one dominant.
From such counts he drew the rules later known as the laws of segregation and independent assortment, which implied invisible factors, now called genes. His abbot discouraged the work, reporting that the bishop had giggled at detailed pea genealogies, and the leading botanist Carl Nägeli failed to grasp it in their letters. Most biologists then believed parental traits simply blended. Charles Darwin never saw the paper. Mendel reportedly told a friend that his time would come.
Elected abbot in 1868, he was swallowed by administration and a long fight against state taxes on religious houses. He died of kidney disease in 1884, with the composer Leoš Janáček playing the organ at his funeral, and his successor burned his papers. The last three of his seven pea genes were identified only in 2025.
Source: Gregor Mendel
