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
acquaitc reptiles
went back to water SECONDARILY
reptile features
break from acquaitc hbabit
have waterpooof skin; different respriation
have high metabolic rate and active life cycle
have a hard shelled egg with internal membranes; most are oviporous and vivapoours (shelled and external eggs)
amniotic egg
egg with internal layers (amnionn, allantois chorion)
- can accunulate nitrogneous waste
american alligarot
dpeendent on temprature for offspring sex determiniation or TSD
theropods
group of dinosaurs; ancestors of birds
- include tyrannosauarus, velociraptor
extinction of dinosaurs
65 million years ago
thomas henry huxley
notes similarties between Achaeopteryx and Birds
Achaeopteryx
150 mya fossil; had lizard features (tail and teeth) but also wings and feathers; intermediate between theropods and dinosaurs
feathered dinosaurs
discoverd in China in 1990s; show ‘nonflying donsuars’ with feahers; for warming and display pruposes
feathers uses
- flight
- warmth
- communication
-camaflagouge
0display
feather structure
assymetircal and intriciate for gifigity
birds have
feathers
warm body
hollow bones
high metabolic rate
mammals
vital instualtion by hair (alpha keratin)
amniotic egg
mammary glands and production of milk (lactation)
store energy as fat reserves
complex teeth
synapsids
ancestors of the mammals
diphydonty
two sets of teeth (milk teeth and full size jaw)
occlusion
matches between teeth; gives ability to chew and grind food
types of mammales
- monotremes (egg laying)
- marsupials (puched animals)
- placentals (long pregnancies and no pouch)
monotreme
egg laying
platypus, echdina, anteter
only non- therian
therian
having a live birth; conssit of placental and marsupial
marsupials
give birth to immature infants and nourish them in bouch
kangaroos, wompants, opposums, koala
placentals
longer pregnancies and no pouch
ecological diversity
placental animal lineages
.1 afrotheria
- xenartha
- laurasiatheria
- euarchontoglires
afrotheria
african lineages
elphants, aardvark and manatees
xenarthia
americas lienages
anteaters, sloths armadillos
laurasiatheria
mammals of europe/asia
carnivores like dogs, cats, whales, bats, horses
euarchontoglires
primates and rodents