FINAL EXAM DINOSAURS

Question 1

laurasiatheria

Answer 1

• 7 extinct orders
• 1: order chiroptera.. vampire bats
• 2: order carnivora
• 3: order perissodactyla
• 4: order cetartiodactyla

Question 2

Order carnivora

Answer 2

cats, dogs, bears, weasels, skunks, seals, walruses

Question 3

order perissodactyla

Answer 3

• odd toed hoofed mammal
• rhinoes, horses, zebras
• digest cellulose in intestine

Question 4

order cetartiodactyla

Answer 4

• artiodactyla
• even toed hoofed mammals
• camels, pigs, cows, hippos

Question 5

devonian period

Answer 5

• precursor for all major fish groups present

Question 6

late devonian extinction

Answer 6

• 80% all marine species extinct
• hypothesis:
• asteroid
• rise of plants/phytoplankton… eutrophication (low O2)
• volcanic activity

Question 7

tetrapod/amphibin origins

Answer 7

• association with late devonian extinctions
• fish to tetrapod
• evodevo: hox genes + limb development

Question 8

transitions needed to make land dwelling tetrapod

Answer 8

• fins to limb
• water to land body and jaw
• water to air breathing
• water to air hearing

Question 9

kenichthys

Answer 9

• early devonian period
• sarcopterygian
• external and internal nostrils

Question 10

eusthenopteron

Answer 10

• middle devonian period
• sarcopterygian
• internal nostrils
• limbs with distinct humeroud, ulna, radius
• femur, tibia, fibula

Question 11

elpistostege

Answer 11

• middle devonian period
• oldest digits

Question 12

pandrichthyes

Answer 12

• middle devonian period
• limbs with digits
• stronger shoulders
• transitional ear
• hyomandibula

Question 13

tiktaalik

Answer 13

• late devonian period
• fisha pod
• terrestrial like front limbs
• flexible neck, hyomandibula, fully free of jaw
• flexing jaw

Question 14

acanthostega

Answer 14

• late devonian
• all limbs and digits well developed
• hyomandibula fully in ear - stapes
• aquatic tail
• no vertebral column arch
• small lungs and gills

Question 15

ichthyostega

Answer 15

• late devonian
• able to walk on land
• arched back
• strong ribs
• small lungs
• small gills

Question 16

emergence of new body plan in carboniferous tetrapods

Answer 16

• distinct terrestrial characteristics
• limbs
• snout/jaws enlarge
• fish scales disappear
• stapes in ear
• arched back

Question 17

carboniferous period

Answer 17

• large amphibian abundance and diversity
• age of amphibians

Question 18

gerobatrachus (permian period)

Answer 18

• frogamander

Question 19

reptilomorphs

Answer 19

• carboniferous
• where amnion allows independence from water reptiles begin to morph
• doesnt fossilize well

Question 20

casineria

Answer 20

• early carboniferous
• amphibian skull
• reptile limbs

Question 21

solenodonsaurus

Answer 21

• carboniferous period
• eggs in terrestrial nests

Question 22

synapsida and sauropsida

Answer 22

• two reptile groups
• synapsid:
  1 TF, air movement via diaphragm, alveolar lungs, 2 way air flow
• sauropsida:
  0-2 TF (anapsida, diapsida)
  air movement via air sac, gizzard, faviolar lungs, 1 way air flow

Question 23

oldest sauropsids

Answer 23

• hylonomus paleothyris
• full reptilian bone structure
• many terrestrial nests
• anapsids
• look like modern lizards

Question 24

petrolacosaurus

Answer 24

• petrolacosaurus:
• oldest fossil record
• nocturnal
• small sharp teeth
• insects inside them

Question 25

permiam triassic extinction event

Answer 25

• great dying
• 90% of all organisms dying
• volcanic activity… siberian traps…
• high CO2, CH4 and H2S in atmosphereq

Question 26

ichthypterygia, sauropterygia

Answer 26

• ichthyosaurs and plesiosaurs
• triassic
• ichthy: similar body plan and lifestyle as dolphins, viviparous
• plesio: heavy body, limbs paddle like, long neck, fish eaters

Question 27

archosaurs

Answer 27

• late permian period
• ruling reptile
• large skull fenetrae for large muscle
• serrated teeth
• femus trochanter: muscle attachment, indicative of bipedalism

Question 28

pterosauria

Answer 28

• late triassic
• winged lizard
• elongated 4th finger
• keeled sternum
• pneumatized bones

Question 29

Dinosaurs

Answer 29

• ornithischia (bird hip) and Saurischia (reptile hip)

Question 30

Ornithischia

Answer 30

• medium sized herbivores
• bipedal herbivores
• duck billed dinosaurs

Question 31

saurischia

Answer 31

• sauropods: large herbivores
• theropods: bipedal carnivores

Question 32

Dinosaur extinction when?

Answer 32

66 mya
cretaceous-paleogene boundary (K-Pg) : the major extinction event, 70% of all plants and animals

Question 33

asteroid hypothesis: What caused the extinction?

Answer 33

• asteroid
• Luis and Walter Alvarez… iridium in earth soil, result of asteroid
• gulf of mexico, evidence of huge wave action
• chicxulub crater: crater is 110m wide, 12 miles deep

Question 34

What killed living things when the asteroid struck?

Answer 34

• short term: (s to days)
  earth quakes, global heat pulse, tsunami
• medium term (m to y)
  debris ejected, caused 90% sun decrease, temp decreased 20 deg C
• long term: (dec to cen)
  CO2 from limestone, cause greenhouse effect and sulfur

Question 35

volcanic activity: Deccan Plateau of India

Answer 35

• CO2 increased due to increase in Volcanic activity
• created the Deccan traps

Question 36

Reptile to mammal transition

Answer 36

• posture: reptile is sprawled… to upright mammal
• reduction in lower jaw bone
• teeth differentiation
• middle ear: one to 3 bones
• jaw articulation: quadrate connect to articular bone (reptile)… squamosal connect to dentary (mammal)

Question 37

Synapsids

Answer 37

• 1 TF
• makes skull lighter
• more attachment points

Question 38

Earliest synapsids

Answer 38

• pelycosaurs
  mammal like: canines, no scales (smooth), eccrine glands
  reptile like: multiple bones in lower jaw, one middle ear bone, jaw articulation, sprawled
• highly vascularized sails for thermoregulation

Question 39

Therapsids

Answer 39

• incisors, canines, premolars, molars
• hair
• bones: highly vascularized… endothermy
• erect limb posture, body held high
  allows for avoidance of carriers constraint (squeezing lungs and air back n forth when running)
• large herbivores and predators

Question 40

cynodonts

Answer 40

• full teeth differentiation
• fewer lower jaw bones
• vibrisse
• nasal turbinates: structures in nasal passages
• high diversity

Question 41

Mammaliaformes

Answer 41

• triassic
• size reduction
• morganucodon
• hadrocodium

Question 42

morganucodon

Answer 42

• morgie: mouse sized
• tree climber
• double jaw articulation:
  -articular- quadrate (reptilian)
  squamosal-dentary (mammalian)
• teeth growth rings

Question 43

hadrocodium

Answer 43

• oldest fossil with 3 middle ear bones
• full mammalian jaw articulation
• eggs

Question 44

Eutherians

Answer 44

• Juramaia Sinensis
• Eumaia

Question 45

Juramaia Sinensis

Answer 45

• oldest known eutherian
• mammalian characterstics, NOT placental

Question 46

Eumaia

Answer 46

• “dawn mother”
• full mammalian characteristics
• placenta

Question 47

Eutherian Radiation

Answer 47

• rapid diversification after K-pg