EVERYDAY SCIENCE

Detailed explanation-1: -Homologous structures are structures that are similar in related organisms because they were inherited from a common ancestor. These structures may or may not have the same function in the descendants. Figure below shows the hands of several different mammals. They all have the same basic pattern of bones.

Detailed explanation-2: -Structures inherited from a common ancestor are called homologous structures, or homologies.

Detailed explanation-3: -Homologous structures share a similar embryonic origin; analogous organs have a similar function. For example, the bones in the front flipper of a whale are homologous to the bones in the human arm. These structures are not analogous. The wings of a butterfly and the wings of a bird are analogous but not homologous.

Detailed explanation-4: -Homology indicates common ancestry and analogy indicates different ancestry. Homology occurs when the same structure develops along different directions due to adaptations to different needs.

Detailed explanation-5: -Homologous structures occur in organisms that are derived from a common ancestor, while analogous structures do not.