deuterostomes III; vertebrates on land Flashcards
coelacanth
lobe fish; living fossil; discoverd off coast of south africa
- has flesh fins and can walk in open sea
- part of the sacroptergyians
sacropterygian
lobe finned vertebraes
sacropterygian groups
- coelacanths
- tetrapods
- lungfish
devonian era
400 million years ago; when lung fish and coelacanth developed
tetrapod relations to other groups
closer to lungfish than colecanth (according ot molecular data)
vertebrae
amphibians
reptiles/birds
mammals
what did animals have to have to live on land
obtian oxygen from air
find/catch food
carry body weight and move on land
avoid drying out
lungfish
use lungs to breathe air AND gills to get oxygen from water
acanthostega
365 mya fishy fins with joined elements skeeleton elements live inw ater, used gills, could have foraged on lamb intermediate between fish and tetrapod
tiktaalik/panderichthys
the 'fisha pod' 375 mya fishy fins skeeleton elements intermediate between fish and tetrapod
icthyostega
also had stronger axial skeleton and long bony projects
amphibian examples
caellicians, newts, frogs and toads, salamanders
frog
e.g. xenopus; only aquatic
salamander
american ‘hellbender’
amphibian features
- skin not waterpoof; need moist environment
2. larvae of most are tadpools with gills (dual life sycle)
reptiles
lizards, snakes, rutles, crodoiles, tutarara of new zealand
reptile ancestors
marine icthyosaur
dinosaurs
pterosaurs (winged)
plesiosaurs