Animal biodiversity - Reptiles and birds Flashcards
what gives amniotes their name?
embryos develop in shells with 4 membrane layers eliminating the larval stage
what are the 4 extraemembryonic layers called and their roles?
1) amnion - protection
2) allantois - waste and gas exchange
3) chorion - gas exchange
4) yolk sak - provides nutrients
what are the 3 amniote lineages and how many fenestra (windows in skull) does each have?
1) anapsid - no fenestra
2) diapsid - 2 fenestra
3) synapsid - 1 fenestra
is the phylum reptile paraphyletic or monophyletic?
paraphyletic
what are reptiles reproductive strategy?
internal fertilisation and lay eggs on land
what are 2 metabolic features of reptiles?
1) 4 chambered heart
2) ectothermal
3 structural features of reptiles
1) scaly keratinised skin
2) heavier skeleton with strong joints
3) complex muscle and nervous system
when do the oldest reptile fossils date back to?
300mya carboniferous
what is it thought early reptile forms fed on?
invertebrates
when and what was the first radiation in reptiles and what did the second radiation lead too?
permian led to anapsids, diapsids, synapsids and second led to dinosaurs
3 reasons why reptiles are incapable of sustaining rapid motion
1) stride is short
2) ectothermic -glycolysis rather than oxidative metabolism
3) the way close limb segments move
4 pieces of evidence dinosaurs were endothermic?
1) long strides
2) legs below body
3) predator/prey relationships
4) vascularised bones
2 pieces of evidence dinosaurs were ectothermic
1) warm mesazoic
2) high surface area to volume ratio
2 features of the order chelonia to help protect them from predators ?
1) bony dermal plates form shell
2) retractable limbs
what does the order squamata include?
lizards and snakes
what are 2 features snakes have lost?
1) eyelids
2) limbs
what are 2 specialisations snakes have for finding prey?
1) jacobsons organ senses smell
2) pit organs sense heat
what are the 2 features of the order crocodilia which adapts them to life in water?
1) broad tail
2) eye, ear, nose openings on top of head
how do you define the class aves?
by the presence of feathers
5 features which make birds light and able to fly?
1) reduced organs (1 ovary)
2) keratin bill
3) honeycomb bone structure
4) no teeth - food ground in gizzard altering centre of gravity
5) large pectoral muscle giving power for flight
what is the shape of birds wings?
aerofoil shaped
how are feathers held together?
barbs and hooked barbules
what are feathers made from?
outgrowths of keratin from skin
how do aves regulate body temp?
endothermic with feathers and fat for insulation
do birds see in colour and can they learn?
yes and yes
what is the evolutionary origin of birds?
they arose from bipedal dinosaur theropod
what are the 2 hypotheses for the origin of flight?
1) ancestors were climbers and they evolved to glide to ground
2) evolved as an adaptation for catching and later aided rapid running, jumping and gliding
what are the 2 modern groups of birds?
1) ratites - can’t fly
2) carinates - great variety adapted to many environments
