Herps test 2

reptiles are a _______ group

paraphyletic - some but not all of a common ancestor (excluding birds)

what separates mammals from the rest of the amniotic tetrapods?

mammals have synapsid skulls that have one pair of fenestrae while reptiles do not have synapsid skulls

mammals are _______ and reptiles are ____________

synapsid, sauropsids

sauropsids are split into two groups: _____ and ______

lepidosaurs, archosaurs

archosaurs

crocodiles, alligators, and caimans

lepidosaurs

tuataras, lizards, and snakes

most reptiles are _________ while turtles are _______

diapsids, anapsids

four orders within reptilia

testudines (turtles), crocodylia (crocs gators etc), squamata (snakes and lizards), and rhyncocephalia (tuataras)

shared characteristics among reptiles

non-synapsid skulls, amniotic eggs, internal fertilization, ancestral single penis, epidermal scales, at least one lung

shared characteristics of lepidosaurs

ectothermic amniotic tetrapods, skin sheds in one piece, transverse vents, three chambered heart

order squamata suborders

lacertilia (lizards), serpentes (snakes), amphisbaena (legless reptiles w small eyes)

this trait has repeatedly evolved independently in squamata

limblessness

difference between snake and legless lizard

snakes have no external ear while lizards do

tuataras are ______ to new zealand

endemic

parietal third eye

many lizards and tuataras have this third eye that helps with regulating circadian rhythms

archosaur characteristics

amniotic tetrapods, TSD, longitudinal cloacal slit, four chambered heart, teeth set in sockets

testudine characteristics

amniotic tetrapods, no teeth, longitudinal cloacal slit, shells, three chambered heart

what is a turtles shell used for

protection, skeleton for skin and muscle attachment, solar panel for warming, place for storing nutrients

why is a turtle an ecological paradox?

they are the longest living and slowest growing vertebrates

the two most threatened reptile groups

testudines and crocydilia

what three factors drive reptile extinction risk globally

climate change, logging pollution, invasives

genotypic sex determination

about 20% of turtles, most lizards, and all snakes

temperature dependent sex determination

80% of turtles, some lizards, and 100% of crocodilians

why might reptiles be especially sensitive to habitat fragmentation

small home ranges/limited mobility, some habitat requirements are highly specific and limited, ectothermy

all reptiles undergo ________ development

direct

aestevation

long term dormancy during prolonged periods of heat

freeze resistance

painted turtles exhibit this and lower their freezing point, but it is very risky

deciduous scutes

sheds periodically throughout the year, reduces infection and parasites etc

non-deciduous scutes

only sheds when the shell grows

vomerolfaction

tongue flicking that transports particles to the sensory organ, detection of nonvolatile molecules

pit vipers, boas, and pythons have

infrared reception

territoriality is common in only one group of lizards:

insectivorous lizards that employ a sit and wait foraging mode