the eyes of the octopus and of mammals are analogous structures resulting from convergent evolution, where different structures evolve for the same function , . Conversely, the bones of forelimbs of vertebrates (like whales, bats, cheetahs, and humans) are homologous structures that indicate common ancestry and are a result of divergent evolution , . The thorns of Bougainvillea and tendrils of Cucurbita are examples of divergent evolution (homology) , while the wings of butterflies and birds are examples of convergent evolution (analogy) .