Question

What is the difference between homologous and analogous structures?

Answer 1

Homologous structure: The similar structure in an organism due to common ancestors that perform different functions are known as homologous organs.

Analogous structures: Analogous structures perform a similar function but have different structures as a result of divergent evolution.

	Homologous structures	Analogous structures
Definition:	1. Homologous structures share similar physical properties and common ancestors, but the structures perform very different functions.	1. Analogous structures are functionally similar but not necessarily structurally similar, they are characteristics of different species that have evolved in response to similar environmental challenges.
Anatomy:	2. Homologous structures have similar anatomy.	2. The anatomy of analogous structures is different.
Functions:	3. Perform different functions.	3. They perform similar functions.
Ancestor:	4. They have an identical embryogenic origin.	4. They have a different embryogenic origin.
Environment:	5. They develop due to adaptation to different environmental conditions.	5. The analogous organs or structures are the result of adaptation to similar environmental scenarios.
Evolution:	6. Divergent evolution results in homologous structures.	6. They are the result of convergent evolution.
Example:	7. An arm of a human being, a flipper of a whale, or a fish are all homologous structures, the leg of a dog.	7. From wings of the birds, insects, and bats to fins in fishes and penguins are analogous structures.