61: Sequence of evolutionary innovations in vertebrate classes

Question 1

What genetic event contributed significantly to vertebrate success?

Answer 1

Two rounds of genome duplication.

Question 2

What are examples of jawless fishes in Class Agnatha?

Answer 2

Hagfish and Lampreys.

Question 3

What type of skeleton do jawless fishes have?

Answer 3

Cartilaginous skeleton.

Question 4

How many pairs of gill pockets do jawless fishes have?

Answer 4

Seven or more pairs.

Question 5

Why are some jawless fishes known as “slime fish”?

Answer 5

Due to the production of a thick, sticky slime as a defense mechanism.

Question 6

What evolutionary transition did jawless fishes contribute to?

Answer 6

The transition from filter-feeding to predation.

Question 7

What are key developments in vertebrate evolution attributed to jawless fishes?

Answer 7

Development of a complex head, early backbone, heart with distinct chambers, and a primitive kidney.

Question 8

What evolutionary step is significant for Class Chondrichthyes (Cartilaginous Fishes)?

Answer 8

Development of jaws from modifications of cartilages in the first pharyngeal arch.

Question 9

What key feature did Class Chondrichthyes introduce?

Answer 9

Introduction of predation.

Question 10

What capabilities did the development of Class Chondrichthyes contribute to vertebrate evolution?

Answer 10

Development of bone production capabilities.

Question 11

What are the skeletal features of Class Osteichthyes (Bony Fishes)?

Answer 11

Primarily bone.

Question 12

What are the subdivisions of Class Osteichthyes?

Answer 12

Ray-finned fishes and Lobe-finned fishes.

Question 13

What universal feature do all bony fishes share?

Answer 13

Universal bony endoskeleton.

Question 14

What significant evolution occurred in lobe-finned fishes?

Answer 14

Evolution of lungs leading to pulmonary circulation.

Question 15

What major transition did some lobe-finned fishes undergo?

Answer 15

Transition to land.

Question 16

Into what did lobe fins evolve for terrestrial movement?

Answer 16

Limbs.

Question 17

What group do four-legged amphibians belong to?

Answer 17

Tetrapoda.

Question 18

Describe the reproductive adaptation of Class Amphibia.

Answer 18

Eggs laid in water with indirect development through an aquatic larval stage.

Question 19

What limb evolution did amphibians contribute to vertebrate evolution?

Answer 19

Paired fins evolved into pentadactyl limbs.

Question 20

How did the skull attachment of amphibians contribute to their evolution?

Answer 20

The skull became semi-motile due to the presence of condyles, allowing greater flexibility.

Question 21

What is significant about the auditory development in amphibians?

Answer 21

Evolution of the middle ear with one bone and an external eardrum.

Question 22

What are the key respiratory adaptations in amphibians?

Answer 22

Transformation of posterior nostrils into choanae for nasal breathing and lungs becoming the primary respiratory organs.

Question 23

What digestive and excretory enhancements did amphibians develop?

Answer 23

Development of salivary glands and a motile tongue, cornified skin with multicellular glands, and differentiated intestines.

Question 24

How did the cardiovascular system of amphibians evolve?

Answer 24

The heart evolved into three chambers to support dual circulatory systems.

Question 25

What is the evolutionary significance of amniotes?

Answer 25

Adapted to terrestrial life post-amphibians.

Question 26

What are the key traits of amniotes?

Answer 26

Evolution of amniotic eggs, dry skin, advanced pulmonary respiration, and thermoregulation.

Question 27

What is the function of the egg shell in amniotic eggs?

Answer 27

Provides protection and allows oxygen exchange.

Question 28

What roles do the chorion and allantois play in amniotic eggs?

Answer 28

Facilitate gas exchange and waste management.

Question 29

What is the evolutionary divergence of amniotic eggs?

Answer 29

Led to Sauropsida and Synapsida.

Question 30

What reproductive adaptation is significant in amniotes?

Answer 30

Internal fertilization and amniotic eggs.

Question 31

What physical and functional developments are seen in amniotes?

Answer 31

Elimination of the larval stage, fully motile head, elongated neck, dry skin, and enhanced pulmonary ventilation.

Question 32

What neurological and renal adaptations occurred in amniotes?

Answer 32

Brain development prioritized over spinal cord and transition to compact kidneys.

Question 33

What is the defining characteristic of mammals?

Answer 33

Presence of mammary glands which produce nutrient-rich milk.

Question 34

From which group do mammals descend?

Answer 34

Synapsida.

Question 35

What is the significance of endothermy in mammals?

Answer 35

Maintains constant body temperature, enabling activity across various climates.

Question 36

What dental evolution is significant in mammals?

Answer 36

Development of heterodonty for precise occlusion and efficient feeding.

Question 37

How does the integumentary system of mammals enhance their survival?

Answer 37

Hair-covered glandular skin.

Question 38

What are the key reproductive innovations in mammals?

Answer 38

Mammary glands, expanded nasal conchae, and increased brain size and complexity.

Question 39

How did the reproductive system of mammals evolve?

Answer 39

Viviparity and the evolution of the uterus and placenta in metatherians and eutherians to support embryonic development.

Question 40

What is the correct order?

Answer 40

Agnatha, Chondrichthyes, Osteichthyes, Amphibians, Reptiles, Mammals, Birds