Biology: Characteristics of Reptiles

Characteristics

• Cold-blooded: regulate body temperature using external sources
• Scaly skin: prevents water loss and provides protection
• Lay eggs: oviparous
• Respiratory system: lungs or skin breathing
• Brain structure: simpler than mammals and birds

Types of Reptiles

1. Snakes (Squamata)
   • No legs or eyelids
   • Specialized skin and muscles for movement
   • Venomous or constricting predators
2. Lizards (Squamata)
   • Legs present
   • External ear openings
   • Most species are carnivorous
3. Turtles (Testudines)
   • Shell: bony plates (scutes) on back and belly
   • Flipper-like limbs or webbed feet
   • Omnivorous or herbivorous
4. Crocodilians (Crocodilia)
   • Large, carnivorous predators
   • Armored skin with scutes
   • Strong tails for swimming
5. Tuataras (Sphenodontia)
   • Only living species: Sphenodon punctatus
   • Native to New Zealand
   • Triangular head, spiny crest on back

Adaptations and Defense Mechanisms

• Camouflage and color change
• Venom or toxic secretions
• Spines, quills, or armor plating
• Playing dead (thanatosis)
• Sun-basking and thermoregulation

Characteristics of Reptiles

• Reptiles are cold-blooded, meaning they regulate their body temperature using external sources
• They have scaly skin, which prevents water loss and provides protection
• Reptiles are oviparous, meaning they lay eggs
• They have a unique respiratory system that uses lungs or skin for breathing
• The brain structure of reptiles is simpler than that of mammals and birds

Types of Reptiles

Snakes

• Snakes have no legs or eyelids
• They have specialized skin and muscles that enable them to move
• Snakes are either venomous or constricting predators

Lizards

• Lizards have legs present
• They have external ear openings
• Most lizard species are carnivorous

Turtles

• Turtles have a shell that is made up of bony plates (scutes) on their back and belly
• They have flipper-like limbs or webbed feet
• Turtles are omnivorous or herbivorous

Crocodilians

• Crocodilians are large, carnivorous predators
• They have armored skin with scutes
• They have strong tails that are used for swimming

Tuataras

• The only living species of tuatara is Sphenodon punctatus
• Tuataras are native to New Zealand
• They have a triangular head and a spiny crest on their back

Adaptations and Defense Mechanisms

• Reptiles use camouflage and color change to adapt to their environment
• They have venom or toxic secretions to defend themselves
• Some reptiles have spines, quills, or armor plating to protect themselves
• Reptiles can play dead (thanatosis) to defend themselves
• They use sun-basking and thermoregulation to regulate their body temperature