Explain the Terms Analogous and Homologous Organs

Q: Explain The Terms Analogous And Homologous Organs 

Answer: Analogous Organs- The organs which are similar in appearance and also carry out similar functions but are different in their structures are called Analogous organs. The wings of a bird and the wings of an insect may look similar and are used by them to fly from one place to another. But they are different in their structures. They are an example of Analogous organs. 

Analogous organs are a result of convergent evolution.

 The ancestors of these organisms are not similar but are evolving to be of similar nature due to change in environment. Convergent evolution takes place when organisms that are not related to one another form a relation through similar biological characteristics. When organisms don’t have a common ancestor but develop organs that are similar in their characteristics and uses, convergent evolution takes place. These types of organs are termed as Analogous organs. 

Homologous Organs- Organs that have the same basic structure but they carry out different functions are called homologous organs. The forelimb of humans is used to reach for an object whereas the forelimbs of a lizard are used by them to walk from one place to another. They are an example of homologous organs. These organs provide evidence for the evolution of organisms. 

They justify that organisms have the same ancestors but are genetically different due to evolution. These organisms may have some similar characteristics which can link them to having the same ancestors but due to evolution and difference in the system of ecology, they have different functions to perform. 

When organisms related to one another differ in their characteristics, divergent evolution takes place. Organisms go through divergent evolution when they have similar looking organs that function differently. These types of organs are termed as Homologous Organs.