Classical genetics color, flower color and seed shape. Mendel took peas that had differing phenotypic characteristics and test-crossed them to assess how the parental plants passed the traits down to their offspring. He started by crossing a round, yellow and round, green pea and observed the resulting phenotypes. The results of this experiment allowed him to see which of these two traits was dominant and which was recessive based upon the number of offspring with each phenotype. Mendel then chose to further his experiments by crossing a pea plant homozygous dominant for round and yellow phenotypes with a pea plant that was
Genetics and the Origin of Species to identify that some populations of this species did not have identical sets of genes. Dobzhansky used experimental breeding in laboratories and gardens, and also surveys related to species in nature to help support aspects of organic evolution. The data in his book show the different genetic mutations and chromosomal changes that were observed. These experiments are vital to this book because they illustrate a transition from the laboratory to the greater field of genetics. "Drosophila" enabled researchers to gain a deeper understanding of how scientific knowledge about heredity has expanded and contributed to other areas of biology. By focusing