1. Ashia Rallings Velita Thornton
Bird Evolution
Ashia Rallings
Velita Thornton

2. Origin of Birds: From Water to the Air
Class Saercopterygii (lobe-finned fish) Order Rhipidistia suborder Dipnoi (lungfishes) made the move from water to land
Class Amphibia subclass Labyrinthodontia is the link from Saercopterygii to reptiles

3. Origin of Birds: From Water to Air cont’d
Labyrinthodontia is a stem reptile that had an anapsid skull
Class Reptilia subclass Anapsida order Captorhinida is a stem reptile linking Labyrinthodont amphibians to other reptiles
Class Reptilia subclass Archosauria “ruling reptiles” order Ornithischia (birdlike pelvis) and order Pterosauria (flying reptiles) lead to the modern day aves
Diapsid skull was formed

4. Subclass Archosauria Pterosaur
Descendant of Pterosaurs; one of the first vertebrates to fly
Hollow light weight bones and wings that assisted with flight due to its large size; probably an active soarer

5. Subclass Archaeornithes Archaeopteryx

6. Confuciusornis

7. Who was more closely related?
Three claws not fused to wing
Longer tail with numerous caudal vertebrae
Toothed beak
Bipedal stance
Clavicle
Ankle bones
Sternum is not ossified
Diapsid skull
Light weight bones
Three claws not fused to wing
Shorter tail and legs
Stronger claws
Toothless beak
Bipedal stance
Ankle bones
Diapsid skull
Light weight bones
Archaeopteryx
Confuciusornis

9. Scales
Early fishes had cycloid and ctenoid scales that were dermal with a layer of epidermis covering
while reptiles and birds have epidermal scales
The two are not homologous
Epidermal scales are made of keratin

10. Feathers Make up of feathers Different uses of feathers
Contour feathers
Flight feathers

11. Adaptive for Flight Wing shape Volant adaptation Major flight muscles
External and internal wing anatomy

13. Beaks From toothed to toothless Environment Food source
Secondarily lost teeth
Environment
Food source

14. Sources
Cruickshank, Allan D. and Helen questions answered about birds. Dover Publication, Inc.: New York, 1958.
Feduccia, Alan. The Origin and Evolution of Birds. New Haven: Yale UP, Print.
Liem Karel F , Lance Grande, William E Bemis. Functional Anatomy of the Vertebrates: An Evolutionary Perspective. Thomson Brooks/Cole: United States, 2001
Evolution book

15. ¿QUESTIONS?