Lec 18 Mesozoic life

Question 1

What is the Mesozoic Era known as

Answer 1

Age of Dinosaurs

Question 2

What was rate of recovery from Permian extinction

Answer 2

slow for many groups

Question 3

What was mollusc recovery after extinction

Answer 3

re-adapted to changed environment and became more diverse

Question 4

what is adaptive radiation?

Answer 4

diversification and spreading out of a species into different habitats

Question 5

What happened to ammonoids after extinction?

Answer 5

radiated from 2 to 100 genres

Question 6

What happen to bivalves, gastropods, and sea urchings after permian extinction

Answer 6

increased in diversity during mesozoic

Question 7

What modern sea animal appeared?

Answer 7

modern reef building corals

Question 8

What happened to marine invertebrates in mesozoic

Answer 8

increased in complexity

Question 9

What invertebrate formed reefs beginning in Jurassic?

Answer 9

rudist bivalves (extinct ring shaped 2 shell)

Question 10

what are foraminifera?

Answer 10

single celled plankton with chalky shell

very important for photosynthesis

Question 11

what are ammonites and beleminites?

Answer 11

2 important marine cephalopods that exploded in Mesozoic

Question 12

what happened to the few remaining mammal like therapsids at the beginning of the triassic

Answer 12

the became extinct

Question 13

What diapsid reptiles dominated the triassic

Answer 13

dinosaurs

Question 14

what animal most common terrestrial vertebrate of triassic?

Answer 14

dinosaurs

Question 15

What do lepidosaurs and archosaurs together make?

Answer 15

the diapsids reptiles

Question 16

Lepidosaurs make up what animals

Answer 16

lizards , and snakes

Question 17

What make up archosaurs?

Answer 17

1. crocodyles 2. dinosaurs 3. birds 4. primitive diapsis

Question 18

When did Archosaur group first appear?

Answer 18

Triassic

Question 19

What four characteristics separate Archosaurs from other reptiles?

Answer 19

1. upright feature (morphology) body shape/structure
2. single skull opening
   a. antorbital finestra (opening in front of eye)
3. finestra is a mandible ( open mouth)
4. teeth compressed to the side

Question 20

what single characteristic separated archosaurs?

Answer 20

a single skull opening in front of the eyes

Question 21

What are the 5 orders of archosaurus? hint stop-c

Answer 21

1. saurischia
2. thechodonts
3. ornithischia
4. pterosaurs
5. crocodylia

Question 22

What is the only surviving archosaur group?

Answer 22

crocodylia

Question 23

when did crocodylia first appear

Answer 23

late triassic

Question 24

which group of archosaurs was primitive triassic?

Answer 24

thecodonts

Question 25

which group was ancestor of dinosaur?

Answer 25

thecodont

Question 26

When did first true mammal appear?

Answer 26

early triassic

Question 27

Were mammals successful in mesozoic era?

Answer 27

no

Question 28

Which group was warm blooded endotherms?

Answer 28

mammals

Question 29

which group had advantage cold bloods (ectotherms) or warm bloods (endotherm) during mesozoic?

Answer 29

cold blooded

Question 30

What advantage did cold blood ectotherm have during mesozoic?

Answer 30

Lower food requirement huge advantage | could sleep a lot not look for food

Question 31

What 2 models proposed to explain rise of reptiles over mammals during mesozoic?

Answer 31

1. climate change model | 2. competition model

Question 32

What is of mesozoic climate change model to explain reptile advantage over dinosaurs?

Answer 32

hot arid dry climate advantage to reptiles

Question 33

Why hot dry climate advantage to reptiles and disadvantage to mammals?

Answer 33

1. reptiles have lower food intake requirement a. helps if food source drying up 2. scaly skin reduces water loss

Question 34

What problem with climate change model of mesozoic

Answer 34

Red Beds ... do not form in dry climate

Question 35

what geologic formation found in mesozoic?

Answer 35

red beds

Question 36

What advantage did reptiles have in competition model of mesozoic that explains lack of success of mammals?

Answer 36

Bipedal (walked on two legs upright) of reptiles that progressively developed huge advantage in hunting prey? so remaining therapsids eaten

Question 37

when did bipedal posture develop in reptiles?

Answer 37

middle and late triassic

Question 38

What problem of competition model for explaining why reptiles over took mammal like therapsids to extinction?

Answer 38

carnivores causing the extinction of their prey does not follow ecological model ... (because the hunter would starve themselves