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