Divergent evolution occurs when the same structure develops along different directions due to adaptations to different needs. Forelimbs patterns of whales, bats, and cheetah all have humerus, radius, ulna, carpals, metacarpals, and phalanges adapted to perform different functions.
Sweet potato is a modified root and potato is a modified stem. Flippers of penguins are modified wings, while those of dolphins are modified arms, however both perform the function of aiding in swimming. The eyes of octopus,and mammals are analogous structures that perform similar functions but they have a different origins. This can be seen from the major differences in their anatomy. These are all examples of analogous structures. They develop due to convergent evolution.