Chapter 34 Questions

Question 1

Which trait is shared by all vertebrates except cyclostomes at some point in development?

a. notochord
b. vertebrae
c. cartilaginous skeleton
d. cranium (head)
e. mouth with jaws

Answer 1

e. mouth with jaws

Question 2

When early systematists distinguished cartilaginous fishes from bony fishes, it was not clear when bony skeletons first appeared. What suggests that bony skeletons came first, followed by cartilaginous ones?

a. All fishes except cyclostomes have jaws.
b. Chondrichthyes and Osteichthyes have paired fins and lateral lines.
c. Traces of bone tissue are found in living and fossil Chondrichthyes.
d. The cartilage skeleton of Chondrichthyes is impregnated with calcium.
e. Chondrichthyes do not have swim bladders, as do many Osteichthyes.

Answer 2

c. Traces of bone tissue are found in living and fossil Chondrichthyes.

Question 3

Which correctly describes phylogenetic relationships among birds, mammals, and reptiles?

a. Birds share the closest common ancestor with dinosaurs.
b. Reptiles and birds, but not mammals, are amniotes.
c. Mammals evolved from the rapsid reptiles after the fall of the dinosaurs.
d. Birds and mammals are more closely related to each other than either group is to crocodilian reptiles.
e. Among living species in the group we call reptiles, turtles and snakes are most closely related to each other.

Answer 3

a. Birds share the closest common ancestor with dinosaurs.

Question 4

Which group soon outcompeted amphibians on land due to their watertight skin and eggs?

a. birds
b. mammals
c. reptiles
d. cyclostomes
e. none of the above

Answer 4

c. reptiles

Question 5

Which chordate group has all four key chordate characteristics as an adult, not just as an embryo?

a. lancelets
b. tunicates
c. frogs
d. humans

Answer 5

a. lancelets

Question 6

Which osteichthyan structure allows bony fishes to control their buoyancy using gases from their blood?

a. operculum
b. lateral line system
c. swim bladder
d. cloaca

Answer 6

c. swim bladder

Question 7

Which statement misdescribes the lateral line system?

a. It can be found in aquatic gnathostomes.
b. It is used in digestion.
c. Lateral line organs form a row along each side of the body.
d. Lateral line organs are sensitive to vibration.

Answer 7

b. It is used in digestion.

Question 8

Which is the closest living group to the primates?

a. birds
b. reptiles
c. monotremes
d. amphibians
e. There is not enough information to decide.

Answer 8

c. monotremes

Question 9

If you discovered a fossil that fit between the crocodilians and pterosaurs, what feature would it probably have?
Figure.
a. feathers
b. amniote eggs
c. fins
d. wings
e. milk

Answer 9

b. amniote eggs

Question 10

Which pair has convergent features?

a. snake, caecilian
b. bony fish, chondrichthyes
c. lizard, marsupial
d. bird, monotreme
e. none of the above

Answer 10

a. snake, caecilian

Question 11

In which choice is the first group phylogenetically part of the second group?

a. birds, reptiles
b. eutherians, mammals
c. cartilaginous fish, fish
d. hominins, primates
e. all of the above

Answer 11

e. all of the above

Question 12

If you introduced the following groups of vertebrates to a newly formed island with little surface water, which would probably become dominant?

a. amphibians
b. reptiles
c. bony fish
d. coelacanths

Answer 12

b. reptiles

Question 13

Which group does not belong?

a. cartilaginous fish
b. amphibians
c. mammals
d. tuataras
e. pterosaurs

Answer 13

a. cartilaginous fish

Question 14

Vertebrates and tunicates share

a. jaws adapted for feeding.
b. a high degree of cephalization.
c. an endoskeleton that includes a skull.
d. a notochord and a dorsal, hollow nerve cord.

Answer 14

d. a notochord and a dorsal, hollow nerve cord.

Question 15

Living vertebrates can be divided into two major clades. Select the appropriate pair.

a. the chordates and the tetrapods
b. the urochordates and the cephalochordates
c. the cyclostomes and the gnathostomes
d. the marsupials and the eutherians

Answer 15

c. the cyclostomes and the gnathostomes

Question 16

Unlike eutherians, both monotremes and marsupials

a. lack nipples.
b. have some embryonic development outside the uterus.
c. lay eggs.
d. are found in Australia and Africa.

Answer 16

b. have some embryonic development outside the uterus.

Question 17

Which clade does not include humans?

a. synapsids
b. lobe-fins
c. diapsids
d. osteichthyans

Answer 17

c. diapsids

Question 18

As hominins diverged from other primates, which of the following appeared first?

a. reduced jawbones
b. an enlarged brain
c. the making of stone tools
d. bipedal locomotion

Answer 18

d. bipedal locomotion

Question 19

Which of the following could be considered the most recent common ancestor of living tetrapods?

a. a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of terrestrial vertebrates
b. an armored, jawed placoderm with two pairs of appendages
c. an early ray-finned fish that developed bony skeletal supports in its paired fins
d. a salamander that had legs supported by a bony skeleton but moved with the side-to-side bending typical of fishes

Answer 19

a. a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of terrestrial vertebrates

Question 20

Why do adult urochordates (tunicates) lack notochords, even though larval urochordates have them? Larvae use notochords to ___.

a. aid in swimming; adults are sessile and thus no longer propel themselves
b. induce tissue differentiation; in adults, tissue is already differentiated
c. stiffen their bodies; in adults, the notochord is replaced by a colum of bone
d. organize their nervous systems; adults’ nervous systems are fully developed and do not change

Answer 20

a. aid in swimming; adults are sessile and thus no longer propel themselves

Question 21

If a tunicate’s pharyngeal gill slits were suddenly blocked, the animals would have trouble ___.

a. moving
b. feeding
c. respiring
d. respiring and feeding

Answer 21

d. respiring and feeding

Question 22

Which of the following characteristics is shared by a hagfish and a lamprey?

a. jaws
b. paired fins
c. a rasping tongue
d. a well-developed notochord

Answer 22

d. a well-developed notochord

Question 23

A new species of aquatic chordate is discovered that closely resembles an ancient form. It has the following characteristics: external armor of bony plates, no paired lateral fins, and a suspension-feeding mode of nutrition. In addition to these, it will probably have which of the following characteristics?

a. endothermy
b. legs
c. an amniotic egg
d. no jaws

Answer 23

d. no jaws

Question 24

To reproduce, many plants produce seeds - structures containing embryonic offspring along with nutrients inside a tough coat. These offspring develop after being released by the parent plant. To which animal reproductive “strategy” is seed production most comparable?

a. internal development and ballistic dispersal
b. viviparous reproduction
c. ovoviviparous reproduction
d. oviparous reproduction

Answer 24

d. oviparous reproduction

Question 25

It is believed that the coelacanths and lungfish represent a crucial link between other fishes and tetrapods. What is the major feature in these fish in support of this hypothesis?

a. They have highly evolved nervous and circulatory systems.
b. Like amphibians, they are tied to the water for reproduction.
c. Their fins have skeletal and muscular structures similar to amphibian limbs.
d. They have lungs and are able to breathe air when water is scarce.

Answer 25

c. Their fins have skeletal and muscular structures similar to amphibian limbs.

Question 26

At one time, Chondrichthyes were thought to have split off from other vertebrates before the evolution of bone. Now we have concluded that the Chondrichthyes split off after the evolution of bone had started. This change demonstrates ____.

a. as new evidence emerges, scientists revise their hypotheses
b. scientists accept the simplest hypotheses
c. revisions of hypotheses take many years
d. scientists develop hypotheses and only accept data that confirm their hypotheses

Answer 26

a. as new evidence emerges, scientists revise their hypotheses

Question 27

Suppose, while out camping in a forest, you found a chordate with long, slender, limbless body slithering across the ground near your tent. This critter could be ___.

a. a skate
b. an amphibian
c. a lamprey
d. a mammal

Answer 27

b. an amphibian

Question 28

What is believed to be the most significant result of the evolution of the amniotic egg?

a. Tetrapods are no longer tied to the water for reproduction.
b. Newborns are much less dependent on their parents.
c. Embryos are protected from predators.
d. Tetrapods can now function with just lungs.

Answer 28

a. Tetrapods are no longer tied to the water for reproduction.

Question 29

The evolution of similar insulating skin coverings such as fur, hair, and feathers in mammals and birds is a result of ___.

a. convergent evolution
b. shared ancestry
c. homology
d. evolutionary divergence

Answer 29

a. convergent evolution

Question 30

Which of the following characteristics evolved independently in mammals and birds?

a. jaws
b. bone
c. endothermy
d. amniotic eggs

Answer 30

c. endothermy

Question 31

Suppose you traveled back in time and located the first animals to have evolved feathers. You found that these animals were tree-dwelling ectotherms, able to run quickly but unable to fly. You also noticed that only males had feathers. Which hypothesis of feather evolution would these data most support? Feathers initially evolved in a role associated with ___.

a. insulation
b. gliding
c. courtship behavior
d. flight

Answer 31

c. courtship behavior

Question 32

Mammals and birds eat more often than reptiles. Which of the following traits shared by mammals and birds best explains this habit?

a. endothermy
b. amniotic egg
c. terrestrial habitat
d. ectothermy

Answer 32

a. endothermy

Question 33

Which characteristic is common to all the modern representatives of all major reptilian lineages (turtles, lepidosaurs, crocodilians, and birds)?

a. presence of a notochord
b. presence of teeth
c. ectothermy
d. presence of four walking limbs

Answer 33

a. presence of a notochord

Question 34

Due to its system of air sacs connected to the lungs, the respiratory system of birds is arguably the most effective respiratory system of all air-breathers. Upon inhalation, air first flows into posterior air sacs, then into the lungs, and then into anterior sacs on the way to being exhaled. Thus, there is one-way flow of air through the lungs, along thousands of tubules called parabronchi.
If the inner lining of the air sacs is neither thin nor highly vascularized, then what can be inferred about the air sacs?
a. They are not efficient sites of gas exchange between air and blood.
b. They cannot effectively moisturize the air before it reaches the lungs.
c. They cannot be derived from endoderm.
d. They must not belong to the respiratory system.

Answer 34

a. They are not efficient sites of gas exchange between air and blood.

Question 35

Birds are descended from species that laid eggs in water. It could be argued that embryos of birds still develop in water because ___.

a. the amnion protect the embryo in the same way that a seed coat protects plant embryos of flowering plants
b. the amnion encases each embryo in water
c. the chorion, allantois, and yolk sac provide embryos with nutrients and waste disposal
d. the shell keeps the embryo from drying out

Answer 35

b. the amnion encases each embryo in water

Question 36

Primate evolution and behavior, such as hunting skills, have been directed in part by the development of depth perception. What anatomical change made depth perception possible?

a. location of the eyes on the front of the head
b. diurnal activity
c. a larger brain
d. the formation of compound eyes

Answer 36

a. location of the eyes on the front of the head

Question 37

Female birds lay their eggs, thereby facilitating flight by reducing weight. Which “strategy” seems most likely for female bats to use to achieve the same goal?

a. feed multiple embryos internally using placentas
b. give birth to underdeveloped young, and subsequently carry them in a pouch that has teats
c. refrain from flying throughout pregnancy (about six weeks long)
d. limit litters to a single embryo

Answer 37

d. limit litters to a single embryo

Question 38

With which of the following statements would a biologist be most inclined to agree?

a. Humans evolved from chimpanzees.
b. Humans and other apes are the result of disruptive selection in a species of chimpanzee.
c. Humans represent the pinnacle of evolution and have escaped from being affected by natural selection.
d. Humans and other apes represent divergent lines of evolution from a common ancestor.

Answer 38

d. Humans and other apes represent divergent lines of evolution from a common ancestor.

Question 39

Brown et al. and Morwood et al. reported in 2004 that they had found skeletal remains of a previously unknown type of hominin, now dubbed Homo floresiensis, on the Indonesian island of Flores. These hominins were small (approximately 380 cubic centimeters) as compared with other hominins. The remains of H. floresiensis were found alongside handmade stone tools and the remains of dwarf elephants that also inhabited the island, suggesting that H. floresiensis was able both to make tools and to coordinate the hunting of animals much larger than itself. H. floresiensis is estimated to have lived at the site where the remains were found from at least 38,000 years ago to 18,000 years ago.
Which would be the most feasible method of figuring out to which other hominin species H. floresiensis was most closely related?
a. Compare the type of prey hunted by H. floresiensis to that hunted by each of the other hominin species.
b. Compare the estimated life span of H. floresiensis to that of each of the other hominin species.
c. Compare the average body size of H. floresiensis to that of each of the other hominin species.
d. Compare the skeletal morphology of H. floresiensis to that of each of the other hominin species.

Answer 39

d. Compare the skeletal morphology of H. floresiensis to that of each of the other hominin species.

Question 40

Which of the following is NOT a diagnostic feature of the Chordata?

a. a muscular, post-anal tail
b. notochord
c. pharyngeal slits or clefts
d. vertebrae
e. a hollow dorsal nerve cord

Answer 40

d. vertebrae

Question 41

Which of the following chordates is most likely to look the LEAST like other chordates?

a. embryonic human
b. lancelet
c. larval tunicate
d. adult tunicate
e. adult human

Answer 41

d. adult tunicate

Question 42

Jaws evolved ___.

a. from arthropod jaws
b. from the rasping tongue
c. by modification of the skeletal rods that previously supported the anterior pharyngeal gill slits
d. from the bony armor of ostracoderms
e. by modification of middle ear bones

Answer 42

c. by modification of the skeletal rods that previously supported the anterior pharyngeal gill slits

Question 43

The diagnostic feature of Chondrichthyes is _____.

a. a lateral line system
b. a streamlined, torpedo-shaped body
c. a swim bladder
d. an endoskeleton of calcified cartilage
e. jaws

Answer 43

d. an endoskeleton of calcified cartilage

Question 44

Listed below are four adaptations of terrestrial vertebrates. Which is a characteristic only of truly terrestrial animals with no need to return to water at any stage of the life cycle?

a. lungs
b. hearts with more than two chambers
c. tetrapod locomotion
d. amniotic eggs
e. All of these are essential for a completely terrestrial existence.

Answer 44

d. amniotic eggs

Question 45

There are three major groups of mammals, categorized on the basis of their _____.

a. method of locomotion
b. presence or absence of hair
c. method of reproduction
d. size
e. habitat

Answer 45

c. method of reproduction

Question 46

Vertebrates and tunicates share

a. a notochord and a dorsal, hollow nerve cord.
b. an endoskeleton that includes a skull.
c. a high degree of cephalization.
d. jaws adapted for feeding.

Answer 46

a. a notochord and a dorsal, hollow nerve cord.

Question 47

Living vertebrates can be divided into two major clades. Select the appropriate pair.

a. the marsupials and the eutherians
b. the urochordates and the cephalochardates
c. the chordates and the tetrapods
d. the cyclostomes and the gnathostomes

Answer 47

d. the cyclostomes and the gnathostomes

Question 48

Unlike eutherians, both monotremes and marsupials

a. are found in Australia and Africa.
b. include only insectivores and herbivores.
c. lay eggs.
d. lack nipples.
e. have some embryonic development outside the uterus.

Answer 48

e. have some embryonic development outside the uterus.

Question 49

Which clade does not include humans?

a. osteichthyans
b. lobe-fins
c. diapsids
d. synapsids

Answer 49

c. diapsids

Question 50

As hominins diverged from other primates, which of the following appeared first?

a. language
b. bipedal locomotion
c. the making of stone tools
d. an enlarged brain
e. reduced jawbones

Answer 50

b. bipedal locomotion