Biodiversity - Reptiles and birds Flashcards
what is the amniote egg?
self contained waterproof chamber for development that eliminated the larval stage
benifit of amniote egg
can move away from water
what are the layers of the amniote egg?
- shell - waterproof
- chorion - regulates gas exchange
- yolk sack - nourishes the embryo
- allantois - stores antrogenous waste
- amnion - protects embryo
what is a fenestra
openings in the skull for attachment of jaw muscles, so jaw can open wide
are reptiles monophyletic or paraphyletic?
paraphyletic
number of reptile species
7000
reptile features
4
- amniotic egg
- internal fert
- scales stop water loss
- ossifed skeleton
hypothesis of dinosaur extinction
- outcompeted by mammals
- volcanic explosion
- asteroid
examples of chelonia
3
- turtles
- terrapins
- tortoises
chelonia features
4
- marine, fresh water and terrestrial forms
- sharp horny plates
- retractable limbs
- weak jaws
examples of squamata
2
- snakes
- chameleon
features of crocodilia
(crocodiles and alligators) 2
- live in water
- flattened tail for propulsion
difference between alligators and crocodiles
- alligators lower teeth not visible
- alligators in fresh water, crodiles in salt water
- crocodiles more aggresive
bird features
4
- feathers
- scaly legs
- amniote egg with hard shell
- monophyletic
how are birds modifed for flight
5
- hollow bones
- less organs
- no teeth
- keratin bill
- large pectoral muscle for flight
what did birds evolve from?
from bipedal theropod dinosaur - dinosaur with feathers
3 hypothesies for reason for flight in birds
- chased after prey, feathers helped jumping then gliding
- feathers helped run up inclines, then gliding
- ancestors were climbers, so feathers helped glide to ground
features of ratites
(birds) 3
- lost flight ability bc costly
- large legs, small wings
- not monophyletic
features of carninates
(birds) 2
- have a keel
- flighted birds
examples of carinates
3
- sparrow
- owl
- spoonbill
