Introduction to Reptiles: Characteristics and Diversity

Reptiles are a class of vertebrate animals known for their scaly skin and cold-blooded nature. They first appeared around 312 million years ago, evolving from Reptiliomorpha. Reptiles include turtles, crocodiles, snakes, lizards, and tuatara, but are distinct from amphibians. Key characteristics include scaly skin, which provides a watertight barrier, and being ectothermic, meaning they rely on external temperatures to regulate their body heat. Reptiles lay eggs on land and do not have a larval stage, with young resembling smaller versions of adults. There are over 6,500 species, ranging from the massive saltwater crocodile to the tiny dwarf gecko, with the reticulated python being the longest.

What is the primary distinction between reptiles and amphibians?

• Reptiles have a larval stage, while amphibians do not.

• Reptiles lay eggs in water, while amphibians lay eggs on land.

• Reptiles have scaly skin, while amphibians do not.

• Reptiles are warm-blooded, while amphibians are cold-blooded.

Which characteristic is NOT typical of reptiles?

• Egg-laying behavior

• Scaly skin

• Cold-blooded nature

• Having a larval stage

How do reptiles regulate their body temperature?

• By moving to sunny or shady areas

• By drinking water

• By generating heat internally

• By sweating

Which of the following is the largest reptile by weight?

• Leatherback sea turtle

• Saltwater crocodile

• Komodo dragon

• Green anaconda

What is the smallest known species of reptile?

• Pygmy chameleon

• Dwarf gecko

• Miniature skink

• Tiny tortoise