Question

Identify the examples of convergent evolution from the following.
(a) Flippers of penguins and dolphins
(b) Eyes of cockroach and mammals
(c) Vertebrate brains

Answer 1

Hint: Convergent evolution refers to the same function and different origin of unrelated organisms. They have analogous organs and they adapted to the same habitat. In convergent evolution species do not have a common ancestor.

Complete answer:
Convergent evolution has no common ancestor; they evolve independently. They show common function with the organisms of the same habitat but their body organs are different. The analogous organ is also called homoplasy.
Analogous organ include-
-Wings of insects, birds, and bats- wings of insects, birds, and bats have a common function but their organ structure is different. The Insect wing has a hollow tube, wings of birds are modified forelimb with flesh, skin, muscles, blood, and nerves, the bat’s wing is also a modified forelimb but to show the extension of skin between elongated fingers.
-Fins and flippers- Fins are present in fishes whereas flippers are present in penguins, dolphins, and whales. Flippers are pentadactyl forelimb. The Flipper of a penguin is a modified forelimb whereas the flipper of the dolphin is a direct specialization of the forelimb.
-Eye of octopus and vertebrae- They are ontogenetically different. Octopus eye is the whole extract from skin whereas in the vertebrae only the lens part is part of the skin.
-Tubers- Both sweet potato and potato are tuber but sweet potato is root modification and potato is stem modification.
-Tendrils- Help in climbing but the different plants have different tendril modifications. In smilax tendril form on stipules whereas in gloriosa tendril form on leaf apex.

Additional Information: The eyes of cockroach and mammals are functionally different, the cockroach has a compound eye with many lenses but mammals have a simple eye with a single lens.
Vertebrate brains are of different sizes in different vertebrae. With evolution the size becomes different but the location is the same in all vertebrae.
So, the correct answer is ‘Flippers of penguins and dolphins’.

Note: Divergent evolution is the opposite of convergent evolution. Convergent evolution shows common ancestry and has homologous organs. The homologous organ has the same origin but different function. The reason for the different functions is adaptation.