Question

Which of the following can be a basis of difference between a salamander and a house-wall lizard apart from their habitat?

• A. Egg-laying feature
• B. Cold-blood
• C. Scales on the skin
• D. Three-chambered heart.

Answer 1

Answer:

C. Scales on the skin

Distinguishing Features: Salamanders vs. Lizards

Key Anatomical Differences:

• Skin Texture: A primary difference lies in the skin. Lizards, including house-wall lizards, typically possess dry, scaled skin. These scales are made of keratin and offer protection and prevent water loss. Salamanders, on the other hand, have smooth, moist, and permeable skin, which is crucial for cutaneous respiration (breathing through the skin). Some salamanders may have granular skin, but it lacks the distinct scales found on lizards.

• Body Structure: While both are tetrapods (four-limbed vertebrates), lizards generally have a more robust, angular body shape, often with a distinct neck. Salamanders tend to have a more elongated, slender, and often serpentine body, with a less defined neck region.

• Claws: Most lizards have claws on their toes, aiding in climbing and grip. Salamanders typically lack claws on their digits.

Taxonomic Classification:

• Lizards: Belong to the order Squamata, which also includes snakes. They are reptiles.

• Salamanders: Belong to the order Caudata (or Urodela), which is part of the class Amphibia. They are amphibians. This amphibian status is fundamental to their differing skin characteristics and life cycles.