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
Christianity and science its leadership, grew rapidly in Europe in the 11th and 12th centuries. St.Thomas Aquinas, the Church's "model theologian," argued that reason is in harmony with faith, and that reason can contribute to a deeper understanding of revelation, and so encouraged intellectual development. The Church's priest-scientists, many of whom were Jesuits, have been among the leading lights in astronomy, genetics, geomagnetism, meteorology, seismology, and solar physics, becoming some of the "fathers" of these sciences. Examples include important churchmen such as the Augustinian abbot Gregor Mendel (pioneer in the study of genetics), Roger Bacon (a Franciscan friar who was one of the