1. Birds and the Origin of Flight

2. Major Features The Aves or birds contains about 9,000 species, ranking it second only to the bony fish in number of species Feathers  Associated with flight - the major characteristic feature of birds is the capacity for flight.  modified scales

4. Feathers as Insulation The evolution of feathers may have been important in providing insulation that would help maintain a body temperature higher than that of the surrounding environment.

5. Feathers and Flight Being airborne, birds have more mobility and access to resources. Not all birds are capable of flight, but flightless birds are evolutionarily derived from flying ancestors.

6. Adaptations for Flight Things that fly must be made to fit strict specifications. This is why most birds have a similar body shape, even though they live in very different habitats and have very different diets.

7. Adaptations for Flight Reduction in the weight  hollow construction of the skeleton

8. Adaptations for Flight Fusion and loss of bones and teeth

10. Adaptations for Flight Fused clavicles and keeled sternum

11. Adaptations for flight 4-chambered heart

12. Adaptations for flight - respiration

13. Adaptations for Flight Reduced urogenital system

14. Flight – the basics Lift (airfoil)

15. Flight – the basics

16. Birds are theropod dinosaurs