Download Chapter 20 Questions

Chapter 20 Questions:
Name:_______________________
1. Which levels of the classification in Figure 20.3 do humans share with leopards?
2. What does the phylogenetic tree in Figure 20.4 indicate about the evolutionary relationships
between the leopard, badger, and wolf?
3. Which of the trees shown here depicts an evolutionary history different from the other two?
EXPLAIN.
A.
B.
C.
4.
Suppose new evidence indicates that taxon E in Figure 20.5 is the sister taxon of a group
consisting of taxa D and F. Redraw the tree to accommodate this new finding.
5.
Suppose that species 1 and species 3 have similar appearances but very divergent gene
sequences. Species 2 and species 3 have very different appearances but similar gene sequences.
Which pair of species is more likely to be closely related: 1 and 2, or 2 and 3? Explain.
6.
To distinguish a particular clade of mammals within the larger clade that corresponds to class
Mammalia, would hair be a useful character? Why or why not?
7. Draw a phylogenetic tree that includes the relationships for Figure 20.15 along with birds,
Dimetrodon, Cynodonts, and mammals (See phylogenetic tree on page 392 for pictures of these
animals). Tranditionally, all the taxa shown besides birds and mammals were classified as
reptiles. Would a cladistic approach support that classification? Explain.
8.
What is a molecular clock? What assumption underlies the use of a molecular clock?
9.
Why is kingdom Monera no longer considered a valid taxon?
10. Explain why phylogenies based on different genes can yield different branching patterns for the
tree of all life.