Step 1: Homologous organs are those that share a similar anatomical structure and origin but perform different functions.
Step 2: The forelimbs of vertebrates (e.g., human arm, bat wing, cheetah leg, whale flipper) all have the same basic bone structure (humerus, radius, ulna, carpals, metacarpals, and phalanges).
Step 3: This similarity indicates common ancestry and is a result of divergent evolution.