Tetrapods

Group of tetrapods that probably evolved into modern amphibians (Lissamphibia)

Batrachomorph

Acanthostega

Early tetrapod internal gills retained 8 toes

obstacle on land

Water carries high heat capactiy, meaning drastic temp changes on land

foromen magnum

hole at base of skull

Chorion

membrane that lies under the shell of an egg and allows for diffusion of respiratory gases between the outside environment and the inside of the shell.

Rhipidistia includes

monophyletic grouping of lungfish and tetrapods

Parts of amniotic egg

-Chorion -Amnion -Yolk sac -Allantois

Adaptations to land (respiration)

-loss of internal gills -reduction/loss of operculum -lungs -3 chambered heart and blood separation

Link of Osteolepiforms to tetrapods

-skull roof bones -proximal paired fin bones -labyrinthodont teeth present (enamel infoldings)

Adaptations to land (support and locomotion)

-strengthened pectoral and pelvic girdles -loss of skull bones attached to shoulder (flexible neck) -paired limbs

Tetrapods include

Amphibia and Amniota (reptiles, birds, mammals)

Reptilomorphs

Large reptiles

Lepspondyls

Long bodied reptiles, snake like

occipital condyles

Markings on the base of the Occipital Bone where the skull sits on the 1st vertebrae (atlas) of the neck (bump at base)

Amnion

Membrane that encloses the embryo in protective amniotic fluid

Sister group to tetrapods

Rhipidistia

Early tetrapod-like animals

Tiktaalik and Icthyostega

zygapophyses

bony projections off vertebrae (support) to limits twisting

Alantois

waste storage of an amniotic egg