Guided Readings Questions for Vertebrate Evolution
(based on Campbell Biology Concepts and Connections 7th edition)
1. What are the four distinguishing characteristics of all members of Phylum Chordate?
2. What do tunicates and lancelets have in common with each other?
What makes them different from vertebrates?
Describe and draw a picture of a lancelet and the four chordate features (since you may
not be familiar with them):
Starting with an ancestral chordate, draw a phylogenetic tree of the chordates with the
major innovation/transition at each branch point (i.e. jaws, lungs).
4. What characteristic does the hagfish have that the tunicates and lancelet chordates do
not?
5. What does the lamprey have that the hagfish does not?
What is a lamprey missing that all other vertebrates have?
6. List two key characteristics that developed in sharks and fishes that contributed to their
success:
How did these characteristics contribute to their success?
7. Compare and contrast chondrichthyans with ray-finned fish:
8. “Structure fits function” is a phrase we use in Biology teaching. What makes the body
plan of rays adapted to their lifestyle? What ray finned fish is discussed with a similar
lifestyle and body plan?
9. What is the most diverse group of vertebrates on earth today?
10. What major lineage of fish gave rise to tetrapods (“four legs”)?
True/ False: Fossil evidence suggests that the first tetrapod was a fish with four limbs that
remained in the water but lifted its head to gulp air.
11. What advantages did the early tetrapods have colonizing land?
12. Why do land amphibians NEED to live near water?
13. Name 3 major groups of amphibians. Draw a sketch of each, noting their different
body plans.
14. Examine Fig 19.6. What major trait arose in reptiles, birds, and mammals that did not
exist in amphibians. What does this mean?
15. What features made an early reptile different from an amphibian?
16. What are the major groups of modern “reptiles”?
17. Birds are “feathered reptiles”. What adaptations make birds unique compared to the
other modern reptiles?
18. What are traits unique to mammals?
19. What are the three major lineages of mammals? Write them in order of appearance
and list example organisms and characteristics of each.