Lecture 5: Tetrapods

Question 1

Which groups are included in Osteichthyes?

a) Amphibians and reptiles
b) Ray-finned fish and lobe-finned fish
c) Cartilaginous fish and bony fish
d) Birds and mammals

Answer 1

B)Actinopterygii (ray-finned fish) & Scarcopterygii (lobe-finned fish)

Question 2

Which superclass includes jawed fish?
a) Agnatha
b) Gnathostomata
c) Osteichthyes
d) Chondrichthyes

Answer 2

b) Gnathostomata

Question 3

2. Which class encompasses jawless fish?
   a) Chondrichthyes
   b) Osteichthyes
   c) Agnatha
   d) Placodermi

Answer 3

c) Agnatha

Question 4

What subclass do lobe-finned fish belong to?
a) Actinopterygii
b) Sarcopterygii
c) Chondrichthyes
d) Agnatha

Answer 4

b) Scarcopterygii

Question 5

When did Rhipidistians emerge?
a) Early Jurassic period
b) Early Devonian period
c) Late Permian period
d) Late Cretaceous period

Answer 5

b) Ealry Devonian period

Question 6

Which era did Rhipidistians exist in?
a) Mesozoic era
b) Paleozoic era
c) Cenozoic era
d) Neoproterozoic era
e) None of the above

Answer 6

b) Paleozoic era

Question 7

What major support system is characteristic of Rhipidistians?
a) Cartilaginous skeleton
b) Exoskeleton
c) Notochord
d) Endoskeleton
e) ossified neural and hemal arches

Answer 7

c) Notochord

Question 8

What transitional feature is observed in the notochord of Rhipidistians, distinguishing them from earlier osteichthyans?

a) Fusion of the bones around the notochord
b) Presence of neural spine and arches
c) Cartilaginous composition of the notochord
d) Absence of hemal arches

Answer 8

a) fusion of the bones around the notochord

Question 9

What evolutionary significance do Rhipidistians hold?
a) They are the ancestors of Chondrichthyes
b) They represent the earliest bony fish
c) They link transitional sarcopterygians to tetrapods
d) They are the most primitive vertebrates

Answer 9

c) They link transitional sarcopterygians to tetrapods

Question 10

Which of the following fish groups played a crucial role in the transition from ocean to tetrapods?

a) Actinopterygians
b) Chondrichthyans
c) Osteolepiforms
d) Placoderms
e) Pandericthinds
f) c & e
g) c & d

Answer 10

f) C & E

Question 11

Which of the following statements about Osteolepiforms (Euthenopteron) is correct?

a) They are tetrapod fish.
b) They emerged in the early Devonian period.
c) Their pectoral and pelvic appendages lack transitional structures.
d) Their girdles and limbs are less ossified compared to other fish.

Answer 11

a) They are tetrapod fish.

Question 12

Which evolutionary feature of Osteolepiforms (Euthenopteron) distinguishes them as significant in the transition from ocean to tetrapods?

a) Presence of fully developed digits in their appendages.
b) Emergence in the late Permian period.
c) Lack of ossification in their girdles and limbs.
d) Transitional structures in their pectoral and pelvic appendages.

Answer 12

d) Transitional structures in their pectoral and pelvic appendages.

Question 13

Which of the following fish groups exhibits concentric centra, representing a transitional stage in vertebrate evolution?

a) Osteolepiforms
b) Panderichthids
c) Actinopterygians
d) Placoderms

Answer 13

a) Osteolepiformes
(also Rhipidistian has this)

Question 14

What evolutionary significance is associated with Eusthenopteron?

a) It is a non-tetrapod fish with no transitional features.
b) It represents a transitional form between fish and tetrapods, exhibiting wrist and ankle bones similar to those found in early tetrapods.
c) It is a fully terrestrial tetrapod species that evolved directly from marine ancestors.
d) It is a member of the Class Osteichthyes but lacks any features relevant to the transition to tetrapods.

Answer 14

b) it represents a transitional form between fish and tetrapods, exhibiting wrist and ankle bones similar to those found in early tetrapods
- a non-tetrapod fish

Question 15

In which geological period did Eusthenopteron, an important transitional lobe-finned fish, emerge?

a) Early Devonian period
b) Late Devonian period
c) Early Carboniferous period
d) Late Carboniferous period

Answer 15

b) Late Devonian period

Question 16

What do the ray fins that connect to wrist and ankles from lobe-finned fish, such as Eusthenopteron (type of Rhipidistian), eventually transition into in tetrapods?

a) Dorsal fins
b) Pectoral and pelvic appendages
c) Tail fins
d) Anal fins
e) digits

Answer 16

e) digits

Question 17

Which fossil species serves as an intermediate link between fish and early tetrapods, exhibiting features like wrist-like bones and a neck, indicative of both aquatic and terrestrial adaptations?

a) Eusthenopteron
b) Osteolepiforms
c) Panderichthids
d) Tiktaalik

Answer 17

d)Tiktaalik

Question 18

When did the Tiktaalik emerge?

a) Late Devonian period
b) Early Carboniferous period
c) Late Permian period
d) Early Triassic period

Answer 18

a) Late Devonian period

Question 19

What kind of scales did the Tiktaalik have?

a) Cosmoid scales
b) Placoid scales
c) No scales
d) Keratinized scales

Answer 19

a) Cosmoid scales (bony scales)

Question 20

What anatomical features are absent in Tiktaalik compared to its fish ancestors?

a) Operculum
b) Dorsal fin
c) Spiracle
d) Gill slits

Answer 20

a) Operculum

Question 21

Which structural change is observed in Tiktaalik compared to Eusthenopteron, indicating a transition from fish to tetrapods?

a) Fusion of the skull with the vertebral column
b) Enlargement of the dorsal fin
c) Detachment of the pectoral girdle from the head
d) Reduction in the number of pharyngeal arches

Answer 21

c) Detachment of the pectoral girdle from the head

Question 22

What anatomical adaptation in Tiktaalik allowed for greater mobility of the head, a crucial feature for land-dwelling animals?

a) Fusion of the head to the shoulder girdle
b) Detachment of the pectoral girdle from the head
c) Reduction of the forelimbs
d) Enlargement of the pelvic fins

Answer 22

b) detachment of the pectoral girdle from the head

Question 23

What key adaptation likely evolved around 430 million years ago, facilitating the transition of vertebrates from water to land during the late Silurian to early Devonian periods?

a) The development of wings for flight
b) The ability to breathe air
c) The evolution of highly efficient swimming fins
d) The adaptation of camouflaging skin patterns

Answer 23

b) ability to breathe air

Question 24

Which class of fish possesses swim bladders, allowing for buoyancy control?

a) Chondrichthyes
b) Agnatha
c) Osteichthyes
d) Placodermi

Answer 24

c) Osteichthyes

Question 25

Which breathing mechanism involves the expansion and compression of the buccal cavity to draw water or air into the respiratory system?

a) Dual pump breathing
b) Buccal pump breathing
c) Aspiration pump breathing
d) Lung breathing
e) None of the above

Answer 25

a) Dual pump breathing

Question 26

The order Labrinthoythodonts (early tetrapods) includes which of the three tetrapod groups:

1. Temnospondyls, archosaurs, icthyostega
2. Anthracosaurs, temnospondyls, icthyostega
3. Reptiliomorphs, temnospondyls, acantostega
4. Temnospondyls, Acanthostega & Icthyostega

Answer 26

4. Temnospondyls, Acanthostega and icthyostega

Question 27

What are the key features of Acanthostega, one of the earliest tetrapods?

a) Dermal skull bones and branchial arches
b) Four limbs with digits and polydactyl feet
c) Aquatic lifestyle and gills for respiration
d) Branchial arches and weight-bearing girdles

Answer 27

b) Four limbs with digits and polydactly feet

Question 28

When did Acanthostega, an early tetrapod, emerge?
a) Early Jurassic period
b) Late Devonian period
c) Early Carboniferous period
d) Late Permian period

Answer 28

b) Late Devonian period

Question 29

Which class of early tetrapods is indicative of pentadactyl chiridium?
a) Acanthostega
b) Ichthyostega
c) Temnospondyls
d) Labyrinthodonts

Answer 29

a) Acanthostega

Question 30

Which early tetrapods have dorsal ventral flexion (move head up and down)?
a) Acanthostega
b) Ichthyostega
c) Temnospondyls
d) Labyrinthodonts
e) none of the above

Answer 30

b) Icthyostega

Question 31

Which characteristic is shared by both Acanthostega and Ichthyostega?

a) Presence of dorsalventral flexion in the vertebral column
b) Lack of limbs with digits
c) Absence of internal gills
d) Extended notochord outside the braincase
e) Polydactyl feet

Answer 31

e) Polydactyl feet

Question 32

What distinguishes Temnospondyls from other early tetrapods like Ichthyostega and Acanthostega?

a) Flat skulls
b) Pentadactyl chiridium
c) Complex, folded enamel patterns on teeth
d) More robust limbs and girdles

Answer 32

d) More robust limbs and girdles

Question 33

Which labyrinthodont survived the Paleozoic era, becoming the connection from prehistoric tetrapods to modern amphibians?
a) Acanthostega
b) Ichthyostega
c) Temnospondyls
d) Labyrinthodonts

Answer 33

c) Temnospondyls

Question 34

During which geological period did the order Lissamphibia emerge?
a) Jurassic period
b) Paleozoic era, Carboniferous period
c) Cretaceous period
d) Paleozoic era, Permian period
e) Paleozoic era, Devoninan period

Answer 34

e) Paleozoic era, Devonian period

Question 35

From which order and group did our modern amphibians arise?
a) Order Lissamphibia, group Temnospondyls
b) Order Lissamphibia, group Sauropsida
c) Order Gymnophiona, group Temnospondyls
d) Order Gymnophiona, group Sauropsida

Answer 35

a) Order Lissamphibia, Temnospondyls

Question 36

What is a key indicator of Lissamphibia and modern amphibians (Temnospondyls) that they have in common?

Answer 36

they both lay eggs in the water and lack the egg shell to protect their eggs

Question 37

Which order encompasses frogs, salamanders, and caecilians?
a) Lissamphibia
b) Reptilia
c) Aves
d) Mammalia
e) Temnospondyls

Answer 37

a) Lissamphibia

Question 38

What are the three groups under the Order of Lissamphibia?
a) Salentia, urodela & Gymnophonia
b) Anura, Salentia & Gymnophonia
c) Tunicata, Salentia & Malaentia
d) None of the above

Answer 38

a) Salentia - frogs (anura)
Urodela - Slamanders (Caudata)
Gymnophonia - Caecilians (Apoda)

Question 39

What distinguishes “Anurans” among modern amphibians?
a) Well-developed wings
b) Long tails
c) Lack of tails
d) Four legs

Answer 39

c) Lack of tails

Question 40

What is a characteristic feature of the Salentia group of Order: Lissamphibia?
a) Saltatory locomotion
b) breathing through their skin
c) no tails
d) loss of lungs
e) All of the above

Answer 40

a) Saltatory (jumping) locomotion

Question 41

Which of the following is a characteristic of lungless salamanders (plethodontids)?

a) They have well-developed lungs.
b) They primarily rely on cutaneous respiration.
c) They exhibit highly derived saltatory locomotion.
d) They possess long hindlegs.

Answer 41

b) They primarily rely on cutaneous respiration

Question 42

When did the group Urodela (salamanders) emerge?
a) Early Triassic Period
b) Late Triassic Period
c) Mid Permian Period
d) Late Jurassic period
e) Ealry Jurassic period

Answer 42

b) Late Triassic period

Question 43

Which of the following is a characteristic of caecilians (“Apodans’)?

a) Well-developed limbs for terrestrial locomotion.
b) Highly developed eyes for visual hunting.
c) Absence of limbs and girdles.
d) Saltatory (jumping) locomotion.

Answer 43

c) absence of limbs and girdles
- they have no feet!

Question 44

Which amphibian species is known for its ability to regenerate its limbs?

a) Giant Salamander
b) Poison Dart Frog
c) Axolotl
d) Spotted Salamander

Answer 44

c) Axolotl

Question 45

Which group does the axolotl belong to?

a) Salientia - Anura
b) Urodela - Caudata
c) Gymnophiona - Apoda
d) Crocodylia

Answer 45

b) Urodela - Caudata