Ashia Rallings Velita Thornton Bird Evolution Ashia Rallings Velita Thornton

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

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

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

Subclass Archaeornithes Archaeopteryx

Confuciusornis

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

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

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

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

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

Sources Cruickshank, Allan D. and Helen.1001 questions answered about birds. Dover Publication, Inc.: New York, 1958. Feduccia, Alan. The Origin and Evolution of Birds. New Haven: Yale UP, 1996. Print. http://www.pbs.org/lifeofbirds/evolution/ Liem Karel F , Lance Grande, William E Bemis. Functional Anatomy of the Vertebrates: An Evolutionary Perspective. Thomson Brooks/Cole: United States, 2001 Evolution book

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