His most important observations were made on the Galápagos Islands. Darwin was influenced by other early thinkers, including Lamarck, Lyell, and Malthus. He was also influenced by his knowledge of artificial selection. Wallace's paper on evolution confirmed Darwin's ideas.
An atom is composed of two regions: the nucleus, which is in the center of the atom and contains protons and neutrons, and the outer region of the atom, which holds its electrons in orbit around the nucleus.
If both parents are heterozygous in a monohybrid cross, the offspring will have a phenotypic ratio of 3:1. If both are heterozygous for both traits in a dihybrid cross, the phenotypic ratio will be 9:3:3:1.
