Question 1

Species A and species B have long wings, whereas species C has short wings.Which piece of evidence would best support the hypothesis that long wings are a synapomorphy?

Accepted Answer

If the common ancestor had short wings, then the presence of long wings in species A and B would suggest that long wings evolved as a shared derived trait (synapomorphy) in these species.

Question 2

Refer to the figure.  In the figure, the estimated average rate of amino acid change is about _______ per 100 million years.

Accepted Answer

The answer of Refer to the figure.  In the...

Question 3

Traits in two or more organisms that are similar but not derived from a common ancestor are called

Accepted Answer

Homoplastic traits are those that have evolved independently in two or more organisms but are similar in structure or function. They are not derived from a common ancestor and are often the result of convergent or parallel evolution. Homologous traits, on the other hand, are similar traits that are derived from a common ancestor, while synapomorphies are shared, derived traits that define a particular clade or group. Ancestral traits are traits that are present in the common ancestor of a group and may be shared by all its descendants, while paraphyletic refers to a group that does not include all the descendants of a common ancestor.

Question 4

The _______ of a phylogenetic tree represents the common ancestor, the _______ represent places where lineages diverge, and the _______ axis represents time.(Assume that the tree is oriented as depicted in the textbook.)

Accepted Answer

The node of a phylogenetic tree represents the common ancestor, while the nodes represent places where lineages diverge. The horizontal axis represents time, as phylogenetic trees are meant to show the evolutionary relationships between organisms over time. Therefore, choice D is the correct answer.

Question 5

Consider four species of conifers.Species A and B are sister species.Species C and D are also sister species.The clade containing species A and B is a sister to the clade containing species C and D.Not counting the root as a node, how many nodes would be found in a phylogenetic tree of species A, B, C, and D?

Accepted Answer

The answer of Consider four species of conifers.Species A and...

Question 6

Refer to the figure.  Which statement about the phylogenetic tree (shown) is true?

Accepted Answer

The phylogenetic tree shows a sister relationship between the clade containing the mouse and the clade containing the chimpanzee.

Answer: D 
 The phylogenetic tree shows that the lizard and salamander are grouped together in a clade, and the crocodile is in a separate clade. Therefore, the lizard is more closely related to the salamander than to the crocodile.

Note: The other statements are false. The tree is not polyphyletic (as all organisms in the tree share a common ancestor), it is not based on homoplastic traits (as the traits used to construct the tree are based on homologous structures), the lamprey is not the outgroup (as it is still a vertebrate), and their relationship does not necessarily reflect the evolutionary timeline.

Question 7

Suppose researchers know that two species of crab began diverging from a common ancestor when they were separated by the formation of the Isthmus of Panama 6 million years ago.The genetic divergence between these two species at the hypothetical R6 gene is 12 percent.This rate of evolutionary change at this gene in these species is _______ percent per million years.

Accepted Answer

The answer of Suppose researchers know that two species of...

Question 8

From a survey of Martian life, three hypothetical species are found.These are nicknamed krons, furs, and pars.If krons and furs are sister species, the resulting phylogenetic tree will have 45 homoplasies.If krons and pars are sister species, the tree will have 52 homoplasies.Krons and pars have red body patches, whereas krons and furs have striped bodies.Based on the principles of parsimony, krons and _______ are sister species, _______ a synapomorphy.

Accepted Answer

Based on the principle of parsimony, the hypothesis that requires fewer homoplasies is preferred. Since krons and furs share striped bodies, it is likely that they are sister species. Therefore, the other sister group should be pars. Also, since krons and pars have red body patches, and striped bodies are not shared between these two species, red body patches are likely to be a synapomorphy that distinguishes krons and pars from furs. Therefore, choice C is the best option.

Question 9

Four different phylogenetic trees of a group of salamanders have been proposed.Trees A and B each require 12 homoplasies, but tree A requires 14 synapomorphies and tree B requires 13 synapomorphies.Tree C requires 15 homoplasies and 13 synapomorphies.Finally, tree D requires 10 homoplasies and 15 synapomorphies.According to the principle of parsimony, which tree(s) is/are the most accurate?

Accepted Answer

The principle of parsimony states that the tree with the fewest number of evolutionary changes (homoplasies) should be favored. Therefore, tree D, which requires the fewest number of homoplasies (10) and the highest number of synapomorphies (15), is the most accurate. Trees A, B, and C all require more homoplasies than tree D. Therefore, neither tree A, B, nor C would be considered the most accurate according to the principle of parsimony.

Question 10

The common ancestor of humans and chimpanzees lived about 7 million years ago.Based on a molecular clock, if a slowly evolving gene shows 3 percent divergence between humans and chimpanzees and 12 percent divergence between humans and gibbons, then humans and gibbons diverged from each other _______ years ago.

Accepted Answer

The answer of The common ancestor of humans and chimpanzees...

Question 11

Studies of female platyfishes, whose male counterparts have a variety of tail shapes, show that the females prefer male fish with artificial swordlike structures attached to their tails.This observation is most consistent with the

Accepted Answer

The sensory exploitation hypothesis posits that males can evolve traits that exploit pre-existing sensory biases of females. In this case, the females have a pre-existing preference for sword-like shapes (which may be associated with natural selection for faster swimming), and males with artificial sword-like structures take advantage of this bias to increase their likelihood of successful reproduction.

Question 12

Some species in a hypothetical family of plants are hermaphrodites, and others have flowers with separate sexes.What would be most useful in determining which condition was the derived one?

Accepted Answer

The most useful way to determine which condition was the derived one would be to find an outgroup, which would allow us to compare the ancestral traits of the group to the traits of the hypothetical family. This would help us determine whether hermaphroditism or separate sexes were the derived trait.

Question 13

Your colleague has incorrectly written a species of dwarf salamander as eurycea Hillisi.Based on the rules of binomial nomenclature, _______ is the proper way to write the species name.

Accepted Answer

The answer of Your colleague has incorrectly written a species...

Question 14

Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _______ and SIV is _______.

Accepted Answer

The answer of Phylogenetic analysis of HIV and nonhuman SIV...

Question 15

The table shows the number of DNA sequence changes between different fish lineages along with the divergence time.  Of the three genes, gene _______ is evolving in a way closest to what would be expected under the molecular clock hypothesis.

Accepted Answer

The answer of The table shows the number of DNA...

Question 16

The trait that would be least useful in a phylogenetic analysis would be one that

Accepted Answer

Traits that are easily altered by environmental factors, such as diet, are less useful in phylogenetic analysis because they may not accurately reflect evolutionary relationships. Traits that are stable and less influenced by the environment are more reliable for determining phylogenetic relationships.

Question 17

Refer to the phylogenetic tree below showing the phylogenetic relationships among eight species.Red dots show the appearance of derived traits.  According to the phylogenetic tree, salamanders and mice share _______ of the listed synapomorphies.

Accepted Answer

The answer of Refer to the phylogenetic tree below showing...

Question 18

Refer to the figure.  This phylogenetic tree is based on

Accepted Answer

The answer of Refer to the figure.  This phylogenetic...

Question 19

Unrelated lineages of rodents that moved to islands have increased in size relative to close relatives that are on the mainland.This increase in size is an example of _______ which is a type of _______.

Accepted Answer

The phenomenon described in the scenario is an example of convergent evolution, as distinct lineages of rodents on different islands evolved similar increases in size. This is a case of homoplasy, as the similarity in size was not due to a shared evolutionary history (synapomorphy), but rather due to convergent evolution. The other options are incorrect, as evolutionary reversal refers to the reversion of a species to an ancestral trait and is not applicable here, and synapomorphy refers to a shared derived trait that evolved in a common ancestor, which also does not apply in this scenario.

Question 20

Tomatoes are in the genus Solanum.The family in which this genus belongs is named after it.Hence, tomatoes are in the _______ family.

Accepted Answer

The answer of Tomatoes are in the genus Solanum.The family...

Quiz 21: Reconstructing and Using Phylogenies

Species A and species B have long wings, whereas species C has short wings.Which piece of evidence would best support the hypothesis that long wings are a synapomorphy?

Refer to the figure. In the figure, the estimated average rate of amino acid change is about _______ per 100 million years.

Traits in two or more organisms that are similar but not derived from a common ancestor are called

The ___ of a phylogenetic tree represents the common ancestor, the _ represent places where lineages diverge, and the _____ axis represents time.(Assume that the tree is oriented as depicted in the textbook.)

Refer to the figure. Which statement about the phylogenetic tree (shown) is true?

Studies of female platyfishes, whose male counterparts have a variety of tail shapes, show that the females prefer male fish with artificial swordlike structures attached to their tails.This observation is most consistent with the

Some species in a hypothetical family of plants are hermaphrodites, and others have flowers with separate sexes.What would be most useful in determining which condition was the derived one?

Your colleague has incorrectly written a species of dwarf salamander as eurycea Hillisi.Based on the rules of binomial nomenclature, _______ is the proper way to write the species name.

Phylogenetic analysis of HIV and nonhuman SIV demonstrates that HIV is _ and SIV is _.

The table shows the number of DNA sequence changes between different fish lineages along with the divergence time. Of the three genes, gene _______ is evolving in a way closest to what would be expected under the molecular clock hypothesis.

The trait that would be least useful in a phylogenetic analysis would be one that

Refer to the phylogenetic tree below showing the phylogenetic relationships among eight species.Red dots show the appearance of derived traits. According to the phylogenetic tree, salamanders and mice share _______ of the listed synapomorphies.

Refer to the figure. This phylogenetic tree is based on

Unrelated lineages of rodents that moved to islands have increased in size relative to close relatives that are on the mainland.This increase in size is an example of _ which is a type of _.

Tomatoes are in the genus Solanum.The family in which this genus belongs is named after it.Hence, tomatoes are in the _______ family.