Question

Consider the following.
1. Fins of fishes.
2. Fins of Ichthyosaurs.
3. Flippers of the whale.
Which of the organ(s) given above is/are analogous organs?
A. 1, 2 and 3
B. 1 and 3
C. 2 and 3
D. Only 3

Answer 1

Hint: Analogous structures in evolutionary biology are biological structures that have similar or corresponding functions but do not have the same evolutionary origin.

Complete answer:
Analogous organs are organs that have different anatomy but perform similar functions. They come from different places.
Insect and bird wings, for example. Sweet potatoes and potatoes serve the same purpose as food storage but are of different origins.
Fins of fish: Whale and dolphin dorsal fins are examples of homologous structures. Fish fins, penguins, and dolphin fins are examples of analogous organs.
Fins of Ichthyosaurs: Ichthyosaurs are members of the order Ichthyosauria or Ichthyopterygia ('fish flippers' – a designation introduced by Sir Richard Owen in 1840, though the term is now used more for the Ichthyosauria's parent clade). Fins of Ichthyosaurs are analogous organs.
Flippers of the whale: Dolphin and whale flippers are homologous. They are considered homologous structures because their underlying anatomy is similar. They are similar and share characteristics.

Thus, the answer is Option A: 1, 2, and 3.

Note:
Homologous organs are organs from different animals that have a similar structure but differ in function. The structure of the two animals is similar, but the functions of their organs differ. The frog's forelimbs, man's forelimbs, and the whale's flippers are all examples of homologous organs. These animals have the same structure but perform different functions.