Gregor Mendel was a pioneer in genetics; he discovered the laws of inheritance, which showed genes come in pairs and are inherited from each parent. He worked with over 10,000 pea plants over eight years, noting dominant and recessive traits.
Mendel's laws of heredity were not widely accepted in his lifetime, and he remained rather obscure for much of his life. However, he is widely regarded as the father of genetics. He proved that inherited traits are defined by a gene pair, organisms with alternate forms of genes express the dominant gene and inheriting one trait is not dependent on other traits. There were exceptions to two laws of inheritance, although Mendel did not realize these exceptions in his lifetime.