vertebrate bio Flashcards
what are the four types of native frog and where do they come from
all leiopelma archeyi - northland hockstetteri - north north island hamiltoni - top of south island pakeka - malborough sounds
all the native NZ frogs are t_____. Why?
terrestrial
aquatic tadpole stage would be washed down the mountain streams
give ways in which new zealand native frogs are primative
no tympanic membrane, middle ear or vocal chords
9 presarchal vertebrae but 8 in modern
no tadpole stage
few and large eggs
there are no native u____ in nz. but there e_____ n__ is an inasive species
urodels e.g. salamanders and newts
european newt
native nz frogs can be called g——— frogs
gondwanan
describe the introduced frogs of new zealand
all from oz
have tympanum
ranoidea aurea - green gold bell frog north island
ranoidea - raniformis green southern bell frog wide spread
litoria ewingi - whistling tree frog south island north e.g. hamner springs
what are the problems with coming onto land from the water
oxyegn - all bony fish had lungs
CO2 - concentration increases on land which effects blood ph
desication - less of a problem in a humid climate
air 800 times less dense than water gravity becomes a problem
temperture regulation , water has a higher specific heat capacity so the temperture in the air is less stable
explain why the emergence onto land more likely occured from freshwater
seas or larger and are therefore more homogenous
evolution requires change to work
freshwater ponds are far more variable
describe the alfred romer model - seasonal climate model of land emergencce
give its flaws
move out of the pond to search for another in hot conditoins
if a pond is drying up then it is unlikely that the fish could survive the parched land
describe the pough or tropical rainforest model for emergence onto land
leaves fall into ponds in the rainforest which makes it far more anoxic
fish go to the shallower parts of the pond
pectoral fins allow standing
smaller fish chased into even shallower water
give 6 potential lines of evidence for either side of rthe endo vs ecto dino debate
blood flow phylogentic analysis fossil evidence gigantothermy bone structure growth rates
desccribe the argument that dinosaours were endotherc based on blood flow
the size of the nutruent foramen in the femur acts as a measure for blood flow
crocodiles and reptiles have far smaller than mammals
dinos were even larger than mammals - suggestive of a higher metabolism
describe the dino bone stucture argument
lamellar zonal bone tissue in reptiles
- low density of vascual cannals
- low metabolism
fibro lamellar bone tissue more in mammals
- high density vascualr cannals
high metabolism
dinos bone structure very similar to mammals
desribe the growth rate argument
use growth rings in bones, old bones are metabolised
growth rates are more similar to mammals much faster than modern crocodiles
describe the phylogenetic analysis argument
not conclusive
sit between crorcdiles and birds corcs are ecto birds are endo
describe two bits of fossil evidence for the endo ecto dino debate
CAT scans on dino brains
nasal turbinates increase surface area to humidify air associated with mammals
not present in dinos or were small
some mammals are also missing them
dino lungs are small and simple more like lepidosaurs
low sa to v indicative of a lower metabolism
describe the gigantothermy argument in the endo ecto dino debate
could keep a higher body temperure due to having a very low sa to v
layers of fat insulte the body
could explain high body temp without the need for endothermy
describe the arboreal model for flight evo
trees down
theropods lived by climbing and jumping
grasping toes and winged claws adaptive
elongated wings allow gliding e.g. flying squirrel
generate lift with flapping
what is a flaw with the arboreal model
most theropods were terrestrial
what is the cursorial model for flight
running after insects
exteneded forarms become adaptive to increase distance between leaps as well as feather elongatoin
provides friction to be able to move up slopes
what is the evidence that most theropods were terrestrial
foot structure
modern terrestrial birds flap their wings to gain traction along the ground
describe the argument of ontogeny reflecting phylogeny
quail chicks
as wing develops they were more able to run up slopes
describe the evidence that cursorial model better fits the archeoptryx
first cusorial birds would have had weaker flight muscles e.g. the keel
this matches the evidence from archeoptryx
describe three changes that caused differnces between chordates and vertebrates
movement to a more predatory lifestyle - bigger brain and better sense organs
larger size - more complex and specialised systems
increased activity - means organ systems needed to be faster
describe differnces in the brain between amphioxus and a model primitaive vertebrate
head extends beyond tip of notochord
there is a skeletal support of the brain - cranium
tripartic brain - multicellular sense organs improve distance perception vs simple cerebral vesicle with no specialised sense organs, just some photo reception
lateral line systems to detect water moements
describe differences between the pahrnyx and respiratoin
gill arches used for support and gills used for respiratoin not filter feeding
fewer gill slits with a far more complex structure
water moved over by acitve pumping of water over the gills rather than ciliary action
gills made of cartilage for elastic recoil rather than collagen
describe differnces between feeding and digestion in amphioxus and primitive vert
musucalr movements for digestion through the gut
extra cellular digestion with enzymes as opposed to intracellular digestion
discrete liver and pancrease - midgut is homologus toboth in amphioxus
describe differnces in excretion and osmoregualtion
kidenys use ultrafiltration
through cuts and to cloaca
as opposed to no kidney and cells emptying into the atrium than to outside world
body fluids are equal concentration with water in amphioxus
describe differnces in the heart and circulation in amphioxus vs primitive model vertebrate
neural control of the heart - hormones
3 chambered heart - sinus venosus, atrium, ventricle vs no true heart
blood with haemoglobin involved in o2 and co2 movement and red blood cells
closed circultoy system
describe differences in locomtion between amphioxus and primitive vertebrates
myomers - complex w shape enabling greater propulsion
both have just caudal find but vert has dermal fin rays to increase speed
describe the evo devo hypothesis for bird feathers
feathers are new structures evolved independantly from scales
several stages to their development
1) unbrnached hollow tubular filament formed in a folice
2) subdivisions by barb ridges
3) rachis forms by fusion of barb ridgies
4) interlocking barbules form
evidence in the fossil record of this
beipraosauraus - single filaments
sinornihosauraus - downy pattern
protoarchaeopteryx - interlocking barbules
what is the blitzreig hypothesis
human colonisation of the world 48,000 years ago was the cause of the quaternary mass extinction where we saw the loss of all megafauna
describe the nesting behaviour of dinosaurs
fossil remains of eggs and nests
eggs in elaborate patterns which is suggestive of parental care
layered nesting sites which suggests there were traditional territories
psittacosauraus - sat on top of a brood
mariasauria - young in nest had worn teeth so had been brougt food
nests were 7 meters apart like gannets suggestes territoriality
describe the scale to feather hypothesis for feather development and explain why it is unlikely give some evidence as well
elongated scales to reduce heat load
scale edge frays to provide a downy structure
lengthen for insulation
then co opted for flight
modern feathers are very similar to reptilian scales biochemically - 90% beta keratin
- scales still cover the feet on birds
but the first feathers were not pennaceous instead thet were filament like
describe some avian features of the theropods
hollow bones
theropods had 3 fingers in one hand but contrevirial if the same, frame shift hypothesis suggests same mechanism involving hox genes some lost
semilunate carpal bone allows movement of the hand from side to side
give three theropod dinosaurs and a feature that they sahre wit birds
Oviaprlorasaurs - pennaceous feathers on the forelimb
dromaeosaurus - unicate proccess
troodontidae - large orbits
