Why forelimbs or a human and a bat are homologous structure

Answer 1

The forelimbs of a human and a bat are considered homologous structures because they have a common evolutionary origin, despite their different functions. Both the human arm and the bat wing share the same basic structure, consisting of a humerus, radius and ulna bones, and a hand with digits.

Although the human arm is mainly used for grasping and manipulating objects, and the bat wing is adapted for flight, the underlying structure and bones are similar. This suggests that these structures were inherited from a common ancestor and have been modified over time to suit different purposes.

Further evidence of their homology can be observed in the embryological development of these structures. Both humans and bats develop similar limb buds during early embryogenesis, which go on to form the respective forelimbs.

Homologous structures such as forelimbs in different species provide evidence for common ancestry and evolutionary relationships between organisms. They are considered key evidence for the theory of evolution.