In a monastery garden, Austrian scientist and an Augustinian friar Gregor Mendel invented the science of genetics. He performed experiments on pea plants that demonstrated the laws of inheritance beginning in 1856, long before anyone knew the existence of genes or DNA.
After high school, Mendel joined a monastery dedicated to teaching and scientific research. He spent years as a teacher, while investigating the principles of inheritance. Eventually, he became an abbot and turned his mind to administration and politics. His scientific ideas were neglected in his lifetime, but he is now considered the father of genetics.
Mendel's Laws have been amended slightly but stand firm. Modern geneticists use the term 'gene' where Mendel said 'factor.' He also used the word allele to describe one of the forms of a gene, as in an allele for white pea flowers as opposed to purple.
Dominant and recessive genes
For many traits, organisms inherit two different alleles-forms of a gene-but show only one. Mendel noticed this dominance in the pea plants he studied (which were tall or short) and in certain pea flowers (which were purple or white). The traits did not blend.
Eye color inheritance isn't as simple as once believed. Though most people have brown eyes, and blue eye color is recessive, at least 16 genes affect eye color in one way or another. Gray eyes, green eyes, green eyes with a brown center, and blue eyes with touches of brown are caused by variations in genes. Many genes influence eye color, which is why people's eyes do not look exactly alike.
How could Mendel study inheritance without knowing about genes?
He knew about math, and he knew about logic. He observed effects closely and reasoned out what their causes might be. Then, he performed more experiments to verify his results. He took enormous pains and kept records with scientific accuracy. His results are a measure of his genius.