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Reptile Adaptations Body Covering: reduced water loss

Eggs: could be laid on land

These adaptations appeared 300 million years ago

Reptile Characteristics Dry, waterproof covering made up of scales

Conserve water

Prevent exchange of oxygen & carbon dioxide

Rely on lungs for breathing

Reptile Characteristics Produce eggs covered by a thick, leathery shell

Prevents moisture from escaping

Keeps sperm from entering

Reptile Characteristics 3-Chambered Hearts

Partial wall inside main chamber lessons mixing of high and low oxygen blood

Results in a heart that works as well as our 4-chambered

Reptile Heart

Human Heart

Reptile Characteristics ECTOTHERMS

Good at regulating internal body temperature

Bask in sun when air is cool

Seek shade when too hot

Maintain a steady body temperature

Lizards & Snakes Closely related

ALL snakes & MOST lizards are carnivores

Both have a special jaw hinge

Allows lizards & snakes to swallow their prey whole by increasing the size of their mouths

Snakes Some still have hipbones & remnants of hind legs

Sign they evolved from reptiles

Poor hearing and eyesight

Keen sense of smell & taste

Snake Jaw

Snake Tongue Tongues used to find prey and gather info about

environment

Tip of tongue picks up chemicals

Organ in roof of mouth

identifies & detects odors

Turtles & Tortoises ALL have shells

Little has changed since appearing hundreds of millions of years ago

When in danger, most pull in head, legs, and tails under shell

Turtle Shells Form from bony plates connected to their ribs and

vertebrae

Covered by layer of skin

Color patterns and markings

ComparisonTurtles Tortoises

Flat, streamlined shells

Ponds, lakes, rivers, or ocean

Must return to land to lay eggs

Dome-shaped shells

Land animals

Remain on land all their lives

Alligators & Crocodiles Closest living relatives to dinosaurs

Lizard-like in shape

Can grow as long as small boat

Backs have large, deep scales

ComparisonAlligators Crocodiles

Broad head, rounded snout

Live mostly in North America & Asia

Care for their young

Female protects eggs

After hatching, male and female protect babies

Narrow head, triangular-shaped snout

Live in tropical America, Africa, Asia, & Australia