Lecture 4

Question 1

List the four classes of tetrapods

Answer 1

Amphibia
Reptilian
Aves
Mammalia

Question 2

Examples and Characteristics of Amphibia

Answer 2

Pedicellate teeth
Cylindrical vertebral centra
Two auditory ossicles
Modern frogs and salamanders

Question 3

Examples and Characteristics of Reptilian

Answer 3

Classified based on number of fenestrae (holes in skull) 
Anapsid 
Synapsid 
Diaspid 
Cotylosaur - stem reptile 
Modern snakes and lizards

Question 4

Examples and Characteristics of Mammalia

Answer 4

Jaw articulation pattern: 
Occurs between temporal bone and mandible bone 
Live birth
Endothermy (homeothermy)
Respiratory Diaphragm
Four chambered heart with completely divided ventricle 
Double occipital condyle 
Bony secondary palate 
Dentary - mandible consisting of a single bone 
Loss of interclavicle
Hair/fur 
Posses mammary glands

Question 5

Temnospondyls

Answer 5

Group of Devonian tetrapods that presumably gave rise to modern amphibians

Question 6

Three orders of modern amphibians

Answer 6

Caudates (urodeles)
Anurans
Apodaca

Question 7

Caudates

Answer 7

Possess tale - urodeles

Include modern salamanders

Question 8

Anurans

Answer 8

Lack a tail

Modern frogs and toads

Question 9

Apodaca

Answer 9

Lack limbs
Modern caecilians
Wormlike, externally segmented, burrowing, subterranean amphibians

Question 10

What are the two groups of anapsids

Answer 10

Cotylosaurs (stem reptiles)

Chelonia (turtles…maybe)

Question 11

Cotylosaur Characteristics

Answer 11

Stem reptile
Dermal armor
Skulls laterally flattened rather than dorsoventrally flattened (as in amphibians)
No additional skull openings behind orbits
Captorhinids
Temporalis muscles major jaw closing muscles

Question 12

Diapsid characteristics

Answer 12

Two arches
Two lateral cheek openings behind each orbit
Each opening is bound by a bony arch (lost in many modern diapsids)

Question 13

Distinguishing feature between two groups of dinosaurs

Answer 13

Pelvic girdle
(Ornithischians) - bird-hipped dinos
Saurischians - lizard hipped dinos

Question 14

Three subgroups of modern lepidosaurs

Answer 14

Sphenodon
Snakes
Lizards
All true diapsids- two lateral cheek openings behind orbitals

Question 15

Explain why dinosaurs form a paraphyletic group

Answer 15

Group includes ancestor of birds and dinosaurs but does not include birds

Question 16

List reptilian characteristics found in Archaeopteryx

Answer 16

Bony tail (birds have replaced with bony tail and feathers)
Separate fingers with claws (birds have reduced digits w/out claws)
Teeth (birds lack teeth)

Question 17

List the four theories on the origin of flight

Answer 17

1. Thermal insulation
2. Insect catching net
3. Helped prey pursuit or escape from predation
4. Helped early archosaurs roost at night

Question 18

Earliest group of synapsids

Answer 18

Pelycosaurs

Question 19

Characteristics shared by mammals and advanced therapsids

Answer 19

Secondary palate 
Pterygoid bones solidity to brain case
Enlarged dentary bone 
DIfferentiation of teeth into incisors, canines, and cheek teeth 
Legs pulled in
Ilium extended forward 
Elongated Sacrum 
Feet well-developed 
Jaw articulation pattern

Question 20

Identify mammalian characteristics

Answer 20

Live birth 
Endothermy (homeothermy) 
Respiratory diaphragm 
Four-chambered heart with completely divided ventricle
Neocortex 
Double occipital condyle
Dentary (mandible consisting of a single bone) 
Bony secondary palate 
Hair/fur 
Mammary glands

Question 21

Three groups of modern mammals

Answer 21

Placentals - live birth
Monotremes - egg- laying mammal, retain reptilian cloaca
marsupials - pouches mammals such as possum and kangaroo

Question 22

Earliest group of mammals and their dentition

Answer 22

Morganucodonts- Heterodont dentition with triconodont molars

Question 23

Adaptive radiation

Answer 23

Plants establish terestrialism, inverts followed, tetrapods began to get after them. Lungs developed. Feet got more feety. Ect

Question 24

List and describe some of the requirements of terrestrialism million

Answer 24

CCERD 
Changes in REPRO
Changes in ORGANS FOR SPECIAL SENSES 
Exertion of nitrogenous waste 
Resistance to gravity 
Desiccation