1. Unit 9 Chordates Ch. 31 Reptiles & Birds

2. What Is a Reptile? A reptile is a vertebrate that has dry, scaly skin, lungs, & terrestrial eggs with several membranes

3. Form & Function in Reptiles Well-developed lungs; a double-loop circulatory system; a water-conserving excretory system; strong limbs; internal fertilization; & shelled, terrestrial eggs are the other adaptations that have contributed to the success of reptiles on land

4. Form & Function in Reptiles A shovel-snouted lizard does not move forward, it lifts its feet to limit contact with the hot desert sand

5. Form & Function in Reptiles A sidewinding adder propels itself forward by digging its ventral scales against the dunes while pushing its body into long curving waves

6. Groups of Reptiles The 4 surviving groups of reptiles are lizards & snakes, crocodilians, turtles & tortoises, & the tuatara

7. Diversity of Reptiles

8. Ecology of Reptiles Many are in danger because their habitats have been & are being destroyed Also, humans hunt reptiles for food, to sell as pets, & for their skins, to make bags, boots, & combs

9. What Is a Bird? Birds are reptile-like animals that maintain a constant internal body temperature, & have an outer covering of feathers

10. What Is a Bird? They have 2 legs covered with scales & used for walking or perching; & front limbs modified into wings

11. Form, Function, & Flight Birds have a # of adaptations that enable them to fly These adaptations include highly efficient digestive, respiratory, & circulatory systems; aerodynamic feathers & wings; strong, lightweight bones; & strong chest muscles

12. Form, Function, & Flight Bird bills come in a variety of shapes & sizes, which allows us to get an idea as to their feeding habits

13. Form, Function, & Flight To keep blood moving rapidly, a bird’s heart beats quickly- from 150 to more than 1,000 beats per minute

14. Form, Function, & Flight A bird’s long bones are strong & light because of air spaces In strong flying birds, the chest muscles account for as much 30% of the animal’s mass

15. Diversity In Birds

16. Ecology of Birds Since birds are highly visible & an important part of the biosphere, they can serve as indicators of environmental health