Week 6

Question 1

was pangea before or after the Mesozoic era

Answer 1

before

Question 2

when did the continents begin to break apart

Answer 2

late in the mesozoic era, sea level also rose

Question 3

what effect does pangea breaking have on dino evolution

Answer 3

formed the western interior seaway.
Pangea caused seasonality (extreme weather interior), Pangea broke apart due to extreme heat in the interior, ice capps melted causing sea levels to rise and create the western interior seaway which swallowed most of interior of Canada. This caused more maritime weather which is less extreme and more ideal for living things like dinos. With this break apart the dinos were separated, no longer mixing/evolving together and were now evolving seperatly.

Question 4

what drove diversification out of the dinosaurs

Answer 4

1. pangea breaks up- dinos no more mix cause the continents are split. Dinos and vegitation evolve seperatly (high diversity)
2. pangea- dinos can mix, leading to widespread distributions of families (low diversity)

Question 5

what did dinosaurs eat

Answer 5

ferns, horse tails )sphenopsids), gymnosperms )naked seeds), possibly angiosperms towards end of creatous era as it is found in coprlite

Question 6

evolution of dinosaurs

Answer 6

chordates
vertebrates
tetrapods
amniotes
diapsids
archosaurs
dinosaurs

Question 7

defining feature of chordates and animal

Answer 7

1. notochord
2. pikaia

Question 8

defining features of vertebrates (2) and animal

Answer 8

1. skeleton and jaw/lobes
2. tiktaalik

Question 9

defining features of tetrapods (2) and animal

Answer 9

1. 4 legged & skeleton structure
2. frog

Question 10

defining feature of amniotes and animal

Answer 10

1. amniotic egg- helped in surviving birthing on land
2. mammals (synapsids aka. one hole in head)

Question 11

defining feature in diapsids and animal

Answer 11

1. 2 holes in head (4 total)
2. snake/mosasaur

Question 12

defining features (2) of archosaurs and animal

Answer 12

1. socketed teeth (continues to replace teeth all throughout life)& antorbital fenestra for a stronger jaw
2. pterosaurus

Question 13

tetrapod skeleton

Answer 13

1. four limbs
2. spine
3. girdles (scapula, pubis, illium, ischium
4. skull with mandible
5. tail

Question 14

why is amniote eggs useful for evolution?

Answer 14

• hard like shell, can be laid on land, membrane containing embryo
• reduces dependance on water to lay eggs and resulted in stronger skeletons with less felxible vertebrae. Allowed animals to colonize interior land that is more hot and further from water

Question 15

anapsids

Answer 15

no openings (temporal fenstra)
ex. turtles

Question 16

synapsids

Answer 16

one opening (temporal fenstrae) (2 total, counting both sides of skull)
ex. mammals

Question 17

diapsids

Answer 17

two openings (temporal fenstrae) (4 total)
ex. dinosaurs

Question 18

what animal is a synapsid but part of the diapsids time?

Answer 18

dimetrodon
there was a split 300 MA where dimetrodon was born in diaspid time but was a synapsid

Question 19

euryapsid

Answer 19

type of diaspid that split off from diaspid in the triassic

Question 20

types of euryapsids

Answer 20

1. Ichthyosaurs- triassic to mid creatous, dolphine like reptiles not a mammal
2. Plesiosaurs- Early jurrasic to end of creatous

Question 21

defining feature in dinosaurs and animal

Answer 21

advanced mesotarsal and erect stance

chicken