1. The Rise of Animal Diversity27
The Rise of Animal Diversity
Questions prepared by
Fleur Ferro, Community College of Denver
Michael Dini, Texas Tech University
William Wischusen, Louisiana State University
Ruth Buskirk, University of Texas at Austin

2. move quickly in one direction
What should animals with radial symmetry be better able to do than those with bilateral symmetry?
move quickly in one direction
detect threats from above or below equally well
deal effectively with food distributed homogeneously in 360
focus attention in a single direction
Answer: C
This question is aimed at Concept This question focuses on student misconceptions about radial and bilateral symmetry, one of which is that radial symmetry is always inferior to bilateral symmetry.

3. move quickly in one direction
What should animals with radial symmetry be better able to do than those with bilateral symmetry?
move quickly in one direction
detect threats from above or below equally well
deal effectively with food distributed homogeneously in 360
focus attention in a single direction 3

4. What is true of modern animal phylogenies?
They take no account of an animal’s “body plan.”
They portray an animal’s place on the scale of nature (scala naturae).
They rely solely on molecular (genetic) data.
They are hypothetical.
They are immune from error due to homoplasy.
Answer: D
This question is aimed at Concept 27.3. 4

5. What is true of modern animal phylogenies?
They take no account of an animal’s “body plan.”
They portray an animal’s place on the scale of nature (scala naturae).
They rely solely on molecular (genetic) data.
They are hypothetical.
They are immune from error due to homoplasy. 5

6. increased number of Hox genes for body segmentation
Which of these genetic changes is thought to have led to the increasing complexity of the arthropod body plan?
increased number of Hox genes for body segmentation
changes in regulation of Hox genes for body segmentation
increased number of Hox genes for appendages
changes in regulation of Hox genes for appendages
increased complexity in genes for exoskeleton arrangements
Answer: B
This question relates to Concept 27.3. 6

7. increased number of Hox genes for body segmentation
Which of these genetic changes is thought to have led to the increasing complexity of the arthropod body plan?
increased number of Hox genes for body segmentation
changes in regulation of Hox genes for body segmentation
increased number of Hox genes for appendages
changes in regulation of Hox genes for appendages
increased complexity in genes for exoskeleton arrangements 7

8. Which of the following phyla have a water vascular system?
molluscs
echinoderms
cnidarians
annelids
arthropods
Answer: B
Echinoderms are equipped with a water vascular system that can power their tube feet as well as distribute oxygen and nutrients throughout the organism. 8

9. Which of the following phyla have a water vascular system?
molluscs
echinoderms
cnidarians
annelids
arthropods 9

10. cartilaginous skeleton cranium (head) mouth with jaws
Which of the following traits is shared by all vertebrates, at least in some developmental stages, except the lampreys?
notochord
vertebrae
cartilaginous skeleton
cranium (head)
mouth with jaws
Answer: E
This question relates to Concept Lampreys are jawless fishes, but they have the four other vertebrate features. 10

11. cartilaginous skeleton cranium (head) mouth with jaws
Which of the following traits is shared by all vertebrates, at least in some developmental stages, except the lampreys?
notochord
vertebrae
cartilaginous skeleton
cranium (head)
mouth with jaws 11

12. All fish except Agnatha have jaws.
When early systematists distinguished Chondrichthyes (cartilaginous fish) from Osteichthyes (bony fish), it was not clear exactly when bony skeletons first appeared in the vertebrates. Which of these suggests that a reduction of bone in Chondrichthyes is a derived condition that emerged after the origin of bony skeletons?
All fish except Agnatha have jaws.
Chondrichthyes and Osteichthyes have paired fins and lateral lines.
Traces of bone tissue are found in living and fossil Chondrichthyes.
The cartilage skeleton of Chondrichthyes is impregnated with calcium.
Chondrichthyes do not have swim bladders, as do many Osteichthyes.
Answer: C
This question relates to Concept Options A, B, and E are true but not informative about the phylogenetic relationship; option D is true but calcium deposits are not the same trait as bone. 12

13. All fish except Agnatha have jaws.
When early systematists distinguished Chondrichthyes (cartilaginous fish) from Osteichthyes (bony fish), it was not clear exactly when bony skeletons first appeared in the vertebrates. Which of these suggests that a reduction of bone in Chondrichthyes is a derived condition that emerged after the origin of bony skeletons?
All fish except Agnatha have jaws.
Chondrichthyes and Osteichthyes have paired fins and lateral lines.
Traces of bone tissue are found in living and fossil Chondrichthyes.
The cartilage skeleton of Chondrichthyes is impregnated with calcium.
Chondrichthyes do not have swim bladders, as do many Osteichthyes. 13

14. Birds share the closest common ancestor with dinosaurs.
Which of these correctly describes phylogenetic relationships among birds, mammals, and reptiles?
Birds share the closest common ancestor with dinosaurs.
Reptiles and birds, but not mammals, are amniotes.
Mammals evolved from therapsid reptiles after the fall of the dinosaurs.
Birds and mammals are more closely related to each other than either group is to crocodilian reptiles.
Among living species in the group we call reptiles, turtles and snakes are most closely related to each other.
Answer: A
This question relates to Concept Mammals diverged from stem reptiles early in amniote evolution. Amniotes include reptiles, birds, and mammals. Options D and E do not correctly describe phylogenetic relationships within amniotes. 14

15. Birds share the closest common ancestor with dinosaurs.
Which of these correctly describes phylogenetic relationships among birds, mammals, and reptiles?
Birds share the closest common ancestor with dinosaurs.
Reptiles and birds, but not mammals, are amniotes.
Mammals evolved from therapsid reptiles after the fall of the dinosaurs.
Birds and mammals are more closely related to each other than either group is to crocodilian reptiles.
Among living species in the group we call reptiles, turtles and snakes are most closely related to each other. 15

16. Which of the following groups soon outcompeted amphibians on land due to their watertight skin and watertight eggs?
birds
mammals
reptiles
none of the above
Answer: C
Reptiles have dry, scaly, watertight skin and watertight eggs, which greatly reduced their dependence on water compared to amphibians. 16

17. Which of the following groups soon outcompeted amphibians on land due to their watertight skin and watertight eggs?
birds
mammals
reptiles
none of the above 17

18. Which of the following chordate groups has all four key chordate characteristics as an adult?
lancelets
tunicates
frogs
humans
Answer: A
Lancelets have a notochord, a dorsal nerve cord, pharyngeal slits, and a post-anal tail in their larval forms as well as adult forms. 18

19. Which of the following chordate groups has all four key chordate characteristics as an adult?
lancelets
tunicates
frogs
humans 19

20. Which of the following Osteichthyan structures allows bony fishes to control their buoyancy using gases from their blood?
operculum
lateral line system
swim bladder
cloaca
Answer: C
The swim bladder can be inflated or deflated to control the buoyancy of a fish. 20

21. Which of the following Osteichthyan structures allows bony fishes to control their buoyancy using gases from their blood?
operculum
lateral line system
swim bladder
cloaca 21