Answer: 1. Bats (Mammals) 2. Birds (Aves)
Explanation:
Homologous structures are features with similar underlying structures that may serve different functions but share a common evolutionary origin. One example that does not involve the limbs of vertebrate animals is the forelimbs of bats and the wings of birds.
Example: Forelimbs of Bats and Wings of Birds
1. Bats (Mammals):
- **Structure:** Bats have forelimbs adapted as wings for flying.
- **Function:** The wings of bats allow them to fly and navigate through the air.
2. Birds (Aves):
- Structure: Birds have forelimbs adapted as wings for flying.
- Function:*The wings of birds serve the same purpose – enabling flight.
Despite the different functions (flight in bats and birds), the underlying structure of the forelimbs in both cases is homologous. This homology suggests a common ancestry, and the modification of these structures over time has led to their adaptation for different purposes in the two groups. Homologous structures provide evidence of evolutionary relationships between species.