ANATOMY

Detailed explanation-1: -If two or more species share a unique physical feature, such as a complex bone structure or a body plan, they may all have inherited this feature from a common ancestor. Physical features shared due to evolutionary history (a common ancestor) are said to be homologous.

Detailed explanation-2: -Homologous structures The similar bone arrangement of the human, bird, and whale forelimb is a structural homology. Structural homologies indicate a shared common ancestor.

Detailed explanation-3: -The most important thing to remember about homologous structures is that they share common ancestry. In other words, only organisms that are somehow related to each other can have homologous structures. For example, a chimpanzee’s arm and a human’s arm are homologous structures.

Detailed explanation-4: -Homologies are traits present in two or more organisms that were inherited from the common ancestor of those organisms.

Detailed explanation-5: -Common ancestor: When two organisms came from the differentiation of the same ancestor, this ancestor is referred to as a common ancestor between the species. Common descent: A characteristic in multiple species that was first exhibited by another ancestor of a different species.