1. Birds

2. Specialized Bird Features  Wings  Feathers  Mating  Asserting dominance  Regulation of body temperature  Camouflage  Countershading  Flight

3. Specialized Bird Features  Bones  Pneumatization

4. Specialized Bird Features  Beaks  Feet  Number of toes  Size  Talons/lack of talons  Webbed

5. Feathers  Modified scales  Extension of dermis  Primaries  Long, found at the tip of the wing  Allow for lift during flight  Secondaries  Shorter, near middle of wing  Retrices  Tail feathers

6. Skin  Thin and loose  Uropygial gland  Secretes oil used to preen feathers

7. External Features  Crown  Nape  Beak (upper and lower)  External nares  External auditory meatus  Breast  Abdomen  Limbs  Upper – wings, specialized for flight  Lower – specialized for walking upright and perching  Hallux (back toe/heel)  Tail (with feathers)

8. Skeletal Adaptations  Sternum  Enlarged to support muscles used for flight  Synsacrum  Fused lower vertebrae and sacrum/coccyx

9. Muscle adaptations for flight  Pectoralis; Supracoracoideus

10. Digestive System Organs  Same similar organ structure and order as other vertebrates

11. Digestive System  Crop  At the base of the esophagus  Food storage  Proventriculus: “true stomach”  Site of chemical digestion  Gizzard  After the “true stomach” to break down and mix food with digestive enzymes

12. Respiratory Adaptations  Air sacs extend from the lungs  Syrinx  Lower end of the trachea  Contains internal membranes  Produces bird calls

13. Respiratory Adaptations  Air sacs:  Increase amount of air available  More oxygen for higher metabolism

14. Heart and the Circulatory System  Endothermic  4 chambered heart  Systemic and Pulmonary Circuits

15. Circulatory System

16. Heart

17. Excretory System  Simplified  Kidneys  Uric acid for excretion  Lack of urinary bladder

18. Reproductive System  Simplified reproductive system  Male  Tesis – oval shaped, above kidneys  Female  One ovary  Left side  Both lead to cloaca

19. Reproduction  Internal fertilization  Females can store sperm for later fertilization  Will release eggs from the ovary sporadically  Some species possess a calcified shell – chickens  Amniotic egg  Amnion  Chorion  Allantois  Yolk sac

20. Amniotic Egg