one example of homology is in the forelimbs of tetrapods, vertebrates with legs. The forelimbs of rabbits, frogs, r ds and lizards have very different functions but are of the same skeletal elements 4.4). (Figure made up They share the same set of bones the humerus radius and ulna. These are the same bones seen in fossils of Eusthenopteron, an extinct transitional animal. Hence, common ancestry is demonstrated.