Early Life and Education:
Born July 20, 1822 - Died January 6, 1884
Johann Mendel was born in 1822 to Anton Mendel and Rosine Schwirtlich. He was the only boy in the family and worked on his family farm with his older sister Veronica and his younger sister Theresia. Mendel took an interest in gardening and beekeeping on the family farm as he grew up.
As a young boy, Mendel attended school in Opava. After graduating, he went on to the University of Olomouc where he studied many disciplines including Physics and Philosophy. He attended the University from 1840 to 1843 and was forced to take a year off due to illness. In 1843, he followed his calling into the priesthood and entered the Augustinian Abbey of St Thomas in Brno.
Upon entering the Abbey, Johann took the first name Gregor as a symbol of his religious life. He was sent to study at University of Vienna in 1851 and then returned to the Abbey as a teacher of Physics. Gregor also cared for the garden and had a set of bees on the Abbey grounds. In 1867, Mendel was made Abbot of the Abbey.
Gregor Mendel is most well known for his work with his pea plants in the Abbey gardens. He spent about seven years planting, breeding, and cultivating pea plants in the experimental part of the Abbey garden that was started by the previous Abbot. Through meticulous record keeping, his experiments with pea plants became the basis for modern genetics.
Mendel chose pea plants as his experimental plant for many reasons. First of all, pea plants take very little outside care and grow quickly. They also have both male and female reproductive parts, so they can either cross pollinate or self pollinate. Perhaps most importantly, pea plants seem to show one of only two variations of many characteristics. This made the data much more clear cut and easier to work with for Gregor Mendel.
Mendel's first experiments focused on one trait at a time and gathering data on the variations present for several generations. These were called monohybrid experiments. There were a total of seven characteristics he studied in all. His findings showed that there were some variations that were more likely to show up over the other variation. In fact, when he bred purebred peas of differing variations, he found that in the next generation of pea plants, one of the variations disappeared. When that generation was left to self pollinate, the next generation showed a 3 to 1 ratio of the variations. He called the one that seemed to be missing from the first filial generation "recessive" and the other "dominant" since it seemed to hide the other characteristic.
These observations led Mendel to the law of segregation. He proposed that each characteristic was controlled by two alleles, one from the "mother" and one from the "father". The offspring would show the variation that is coded for by the dominant of the alleles. If there is no dominant allele present, then the offspring shows the characteristic of the recessive allele. These alleles are passed down randomly during fertilization.
Link to Evolution:
Mendel's work wasn't truly appreciated until the 1900s -- long after his death. Mendel had unknowingly provided the Theory of Evolution with a mechanism for the passing down of traits during natural selection. Mendel did not believe in evolution during his life as a man of strong religious conviction. However, his work has been added together with that of Charles Darwin's to make up the Modern Synthesis of the Theory of Evolution. Much of his early work in Genetics has paved the way for modern scientists working in the field of microevolution.