Hugo Marie de Vries was a Dutch botanist and one of the first geneticists. He is known chiefly for suggesting the concept of genes, rediscovering the laws of heredity in the 1890s while apparently unaware of Gregor Mendel's work, for introducing the term "mutation", and for developing a mutation theory of evolution.

Gregor Johann Mendel OSA was an Austrian-Czech biologist, meteorologist, mathematician, Augustinian friar and abbot of St. Thomas' Abbey in Brno (Brünn), Margraviate of Moravia. Mendel was born in a German-speaking family in the Silesian part of the Austrian Empire and gained posthumous recognition as the founder of the modern science of genetics. Though farmers had known for millennia that crossbreeding of animals and plants could favor certain desirable traits, Mendel's pea plant experiments conducted between 1856 and 1863 established many of the rules of heredity, now referred to as the laws of Mendelian inheritance.