Biology of the Vertebrates Study Questions

Note: These study questions are not necessarily comprehensive, nor are they meant to be. They are meant to supplement your lecture notes as you review them, and alert you to the ways in which you should be thinking about the material, and formulate questions to test yourself. Exams will NOT be limited to the material highlighted in these questions, or their formats, so your lecture notes should be your primary reference.

Lecture 1

1. List and describe 3 applications for the study of vertebrate biology, and be sure to provide examples.

2. Which major taxonomic group of vertebrates is the most speciose? The least? What might account for these differences in numbers of species? Roughly what fraction of animals do vertebrates comprise?

3. What is “cladistics”? Define “monophyly,” and describe how this differs from “paraphyly.”

4. Define “synapomorphy” and “plesiomorphy.” Explain how a synapomorphy at one level can be plesiomorphic at another (or vice-versa). Briefly explain how it is that we (humans) are considered ‘bony fish’.

5. Where do vertebrates fit in the larger scheme of organisms?

Lecture 2

1. Describe 3 major evolutionary innovations, or trends, in the vertebrate body plan.

2. List, and briefly describe, each of the major organ systems shared by vertebrates.

3. What are ‘homologous’ bones? In which group (and roughly when in geologic time) does bone appear in the fossil record? What is bone comprised of, and how does it differ from cartilage?

4. Describe the 2 major regions of the vertebrate skeletal system (what features does each contain). Describe the 3 major embryological regions of the skull, and what what each gives rise to.

5. How does the tetrapod vertebral column differ from the ancestral condition (both in its morphology and capacity for movement).

6. Briefly explain the major transitions in the appendicular skeleton from sharks, to bony fish, to lobe-finned fish, and to terrestrial tetrapods.

7. In ancestral vertebrates, such as bony fish, axial muscles are divided into _________. What are the major regions of axial musculature called? With which features are the hypobranchial muscles associated?

Lecture 3

1. What is ‘plate tectonics’ and why does it matter for vertebrate evolution? Define ‘continental drift’ and ‘subduction,’ and provide examples for each.

2. The first fossil records are from which geologic period? How were most of the continental land masses situated during this time, and what were the environmental conditions like?

3. Describe some key features of Myllokunmingia. When did it evolve, and why this fossil is significant for vertebrate evolution.

4. When did the conodonts evolve, and how do we know?

5. Describe some key features of the ostracoderms; when did they evolve, and roughly when did they go extinct? Which group experienced a major radiation during the Silurian? Some ostracoderms had hypocercal tails, and others hetercercal tails – what does this mean? Which group is charaxterized as having brain structures similar to lampreys?

6. Describe some similarities and differences in morphology and biology between the 2 living jawless vertebrates.

7. List 6 main gnathostome characteristics. Roughly when did jaws evolve? Briefly explain Mallatt’s hypothesis regarding the evolution of jaws from jawless, filter-feeding ancestors.

8. List the 4 main gnathostome groups, present between the Silurian and Devonian. Describe some of the major characteristics of placoderms, and how they differ from, say, the ostracoderms.

Lecture 4

1. Name and describe the two major extant clades of cartilaginous fishes. How do these differ from one-another (particularly in terms of skull morphology).

2. How do modern sharks differ from their ancestral counterparts (give at least 3 major characteristics)? When in geologic time did cartilaginous fishes arise?

3. Describe the two major shark radiations. Roughly when did each occur, and how did sharks from the second wave differ from those from the first?

4. List and briefly describe some important characteristics of modern sharks, in terms of their: (a) morphology (general anatomy, shape, size range), (b) physiology (e.g., osmopregulation), and (c) reproductive biology (e.g., fertilization; oviparity/viviparity).

5. What proportion of elasmobranchs are oviparous? Describe two types of viviparous eggs.

6. From video: Describe 2 types of symbiotic relationships between sharks and other fish. True or false: sharks must keep swimming to remain alive. True or false: hammerheads actually do use their heads to bash prey. What is the largest species of shark, and what does it feed on?

Back to Biology of the Vertebrates main page.