BIOL385 LEPIDOSAURIA (LIZARD) EXAM ACTUAL QUESTIONS
AND ANSWERS WITH COMPLETE SOLUTIONS GRADED A++
what is determinant growth
get to adult size and then stops growing
what are the ancestral members of lepidosauria
lepidosauromorphs
what are champosaurus
some consider them ancestral to lepidosaurs, some consider them apart of lepidosaurs
what are champsaurus similar to
crocodiles
how are champosaurus similar to crocodiles
nostrils at end of nose
had secondary palette
existed longer and with crocodiles for a while
What are placodonts also known as?
"walrus-turtles"
when did placodonts evolve and when did they go extinct
in the triassic and went extinct at the end of the cretaceous
what kind of teeth did placodonts have and what did this suggest
very flat teeth sugesting they crushed mollusks
what did placodonts look like they were not built for?
,not built for speed
- slow movement
how are placodonts different from turtles
rather than having a lot of big plates they had a lot of little plates
when did pleisiosaurus persist
into cretaceous
what different lineages did pleisiosaurus separate into
a couple distinct lineages that likely did different things
long necked small headed forms vs. short necked heavy headed forms
ex) elasmosaurus & pliosaurus
what did both lineages of pleisiosaurus appear to do
appeared to sort of row their way through water with oar like fins
what did pleisiosaurus dentary suggest
that they ate big fish or other big things
what looks exactly what people thing the loch-ness monster looks like
elasmosaurus
what is a quire derived form of pleisiosaurus
elasmosaurus
what did elasmosaurus have an increased number of
cervical vertebrae
what were pliosaurus
shorter-necked, larger fin size
, what look somewhat like dolphins (is a reptile tho)
icthyosaurs
how did icthyosaurs paddle through the water
they retained fore and hind limbs
what likely provided the main propulsion for icthyosaurs
their tails
what do icthyosaur fossils suggest
the dorsal fin and upper lobe of caudal fin were not supported by bone, just stiff tissue
mostly supported by muscle
how long were icthyosaurs
2 - 3 m long
when did icthyosaurs go extinct
at end of cretaceous with rest of the dinos
how many species are there of living lepidosaurs
about 67,000 species
What are lepidosaurs?
lizards and snakes
what is the key feature of lepidosaurs
the determinant growth idea
what do most lepidosaurs eat
insects
what is the more derived form of lepidosaurs
rynchocephalians (tuataras)
AND ANSWERS WITH COMPLETE SOLUTIONS GRADED A++
what is determinant growth
get to adult size and then stops growing
what are the ancestral members of lepidosauria
lepidosauromorphs
what are champosaurus
some consider them ancestral to lepidosaurs, some consider them apart of lepidosaurs
what are champsaurus similar to
crocodiles
how are champosaurus similar to crocodiles
nostrils at end of nose
had secondary palette
existed longer and with crocodiles for a while
What are placodonts also known as?
"walrus-turtles"
when did placodonts evolve and when did they go extinct
in the triassic and went extinct at the end of the cretaceous
what kind of teeth did placodonts have and what did this suggest
very flat teeth sugesting they crushed mollusks
what did placodonts look like they were not built for?
,not built for speed
- slow movement
how are placodonts different from turtles
rather than having a lot of big plates they had a lot of little plates
when did pleisiosaurus persist
into cretaceous
what different lineages did pleisiosaurus separate into
a couple distinct lineages that likely did different things
long necked small headed forms vs. short necked heavy headed forms
ex) elasmosaurus & pliosaurus
what did both lineages of pleisiosaurus appear to do
appeared to sort of row their way through water with oar like fins
what did pleisiosaurus dentary suggest
that they ate big fish or other big things
what looks exactly what people thing the loch-ness monster looks like
elasmosaurus
what is a quire derived form of pleisiosaurus
elasmosaurus
what did elasmosaurus have an increased number of
cervical vertebrae
what were pliosaurus
shorter-necked, larger fin size
, what look somewhat like dolphins (is a reptile tho)
icthyosaurs
how did icthyosaurs paddle through the water
they retained fore and hind limbs
what likely provided the main propulsion for icthyosaurs
their tails
what do icthyosaur fossils suggest
the dorsal fin and upper lobe of caudal fin were not supported by bone, just stiff tissue
mostly supported by muscle
how long were icthyosaurs
2 - 3 m long
when did icthyosaurs go extinct
at end of cretaceous with rest of the dinos
how many species are there of living lepidosaurs
about 67,000 species
What are lepidosaurs?
lizards and snakes
what is the key feature of lepidosaurs
the determinant growth idea
what do most lepidosaurs eat
insects
what is the more derived form of lepidosaurs
rynchocephalians (tuataras)
