Monohybrid cross predicts that three quarters of the F2 generation will have the dominant allele's phenotype. And the remaining quarter of the F2s will have the recessive allele's phenotype. This predicted 3:1 phenotypic ratio assumes Mendelian inheritance. This cross was originally used by biologist Gregor Mendel, who crossed two pea plants to obtain a hybrid variety and discovered the dominance relationships between alleles of several genes. Mendel has considered one alleleomorph character for his first experiment that is colour of red and white length of plant-tall and dwarf. Gregor Mendel (1822–1884) was an Austrian monk who theorized basic rules of inheritance. From
Plant genetics put forth by Mendel. W.E. Castle discovered that while individual traits may segregate and change over time with selection, that when selection is stopped and environmental effects are taken into account, the genetic ratio stops changing and reach a sort of stasis, the foundation of Population Genetics. This was independently discovered by G.H. Hardy and W. Weinberg, which ultimately gave rise to the concept of Hardy-Weinberg equilibrium published in 1908. For a more thorough exploration of the history of population genetics, see History of Population Genetics by Bob Allard. Around this same time, genetic and plant breeding experiments in maize