Deck 23: Evolutionary Patterns: Phylogeny and Fossils

Question 1

Individual populations cannot be included as separate taxa in a phylogenetic tree.

Answer 1

False

Question 2

Which of the following statements is always TRUE about sister taxa on a phylogenetic tree?

A)Sister taxa are always the result of speciation events that result in two new genera.
B)Sister taxa always share a most recent common ancestor that is not shared with any other taxon on the phylogeny.
C)Sister taxa are always the result of the most recent divergence event represented on a phylogeny.
D)Sister taxa are always defined by shared ancestral characteristics that have been modified in all other taxa in the phylogeny.

Answer 2

B

Question 3

The phylogeny below shows: (left to right) Zoonar/K. Jorgensen/age fotostock; S Sailer/A Sailer/age fotostock; J & C Sohns/age fotostock; Michael Dick/ Animals Animals-Earth Scenes; FLPA/Jurgen & Christi/age fotostock; Yellow Dog Productions/Getty Images.

A)orangutans and gorillas are more closely related than humans and gorillas.
B)humans and gorillas are more closely related than orangutans and gorillas.
C)the gorilla is the most recent common ancestor to bonobos, chimps, and humans.
D)the orangutan is the most recent common ancestor of all great apes.
E)all great apes walk with an upright gait.

Answer 3

B

Question 4

Based on the diagram below, you predict that the earliest fossil gorilla (which may not resemble modern-day gorillas) would be _____ than the earliest fossil _____. Photo sources: (left to right) Zoonar/K. Jorgensen/age fotostock; S Sailer/A Sailer/age fotostock; J & C Sohns/age fotostock; Michael Dick/ Animals Animals-Earth Scenes; FLPA/Jurgen & Christi/age fotostock; Yellow Dog Productions/Getty Images.

A)older; bonobo
B)younger; bonobo
C)younger; chimp
D)older; orangutan
E)None of the answer options is correct.

Question 5

Examine Figure 23.2 below. What is the sister group to mammals?

A)sauropsids
B)tetrapods
C)birds
D)crocodiles and alligators
E)birds plus crocodiles and alligators

Question 6

Organisms in the same family will all be from the same genus.

Question 7

Examine Figure 23.2 below. If we defined a taxon to include only the coelacanths and lungfish but not their most recent common ancestor, it would be a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 8

A phylogenetic tree is a:

A)hypothesis about the evolutionary history of species.
B)guess about the evolutionary history of species.
C)factual representation of the evolutionary history of species.
D)detailed timeline of a species' evolutionary history.
E)None of the answer options is correct.

Question 9

A population of rodents, called population A, lived together in harmony on a large landmass until one group of the population dispersed to a nearby island. Two million years later, the island population is split into two smaller, equal-sized populations when a river formed across the middle of the island. Now two new species have evolved on the island, A1 and A2. They have replaced the population from which they were derived. Which represents the phylogeny of the populations discussed in this scenario?

A)diagram M
B)diagram H
C)diagram K

Question 10

Which phylogenetic group includes all descendants of a common ancestor and only the descendants of that ancestor?

A)monophyletic
B)paraphyletic
C)polyphyletic
D)genus

Question 11

Examine Figure 23.2 below. The group "fish" includes all vertebrates except the tetrapods. The taxon "fish" is therefore a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 12

Which of the following BEST describes the purpose of phylogenetics?

A)Phylogenetics names species, genus, order, class, phylum, and kingdom.
B)Phylogenetics looks for patterns of relatedness.
C)Phylogenetics compares anatomical or molecular features.
D)Phylogenetics looks for patterns of relatedness and compares anatomical or molecular features.

Question 13

Examine Figure 23.2 below. According to the figure, the closest relatives of turtles are:

A)lizards and snakes.
B)sauropsids.
C)tetrapods.
D)crocodiles, alligators, and birds.
E)hagfish.

Question 14

Figure 23.2 below represents a phylogenetic tree of the vertebrate animals. According to this tree, what is the sister group to the tetrapods?

A)sauropsids
B)mammals
C)lungfish
D)amphibians
E)coelacanths

Question 15

In a phylogenetic tree, a node or branching point represents:

A)the common ancestor from which the descendent species diverged.
B)the species in the fossil record from which the descendent species diverged.
C)one of the descendent species in the phylogeny.
D)the ancestral species from which all species in the phylogeny arose.
E)None of the answer options is correct.

Question 16

Examine Figure 23.2 below. According to this figure, the amphibians are a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 17

Traditional levels of taxonomy are nested in categories from least to most inclusive. This same relationship is also represented on a phylogenetic tree by moving from the terminal (most recent) nodes to the earliest nodes.

Question 18

A taxon that does NOT include the last common ancestor of all its members is a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 19

The diagram below depicts three phylogenetic trees. Which of the three show the same sister group relationships among groups A, B, and C?

A)Trees 1 and 2 are equivalent.
B)Trees 2 and 3 are equivalent.
C)Trees 1 and 3 are equivalent.
D)All three trees are equivalent.
E)All three trees are different: no two are equivalent.

Question 20

Examine Figure 23.2 below. If we define the taxon Actinopterygii to include the ray-finned fish, coelacanths, lungfish, tetrapods, and their most recent common ancestor, it would be a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 21

What types of data can be used to construct phylogenies such as the one below? Photo sources: (left to right) Zoonar/K. Jorgensen/age fotostock; S Sailer/A Sailer/age fotostock; J & C Sohns/age fotostock; Michael Dick/ Animals Animals-Earth Scenes; FLPA/Jurgen & Christi/age fotostock; Yellow Dog Productions/Getty Images.

A)molecular data
B)fossil evidence
C)anatomical, physiological, and developmental studies of extant species
D)molecular data, fossil evidence, and anatomical, physiological, and developmental studies of extant species
E)None of the answer options is correct.

Question 22

A taxon that includes a single common ancestor and some, but not all, of its descendants is a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 23

Consider a generalized tree of life, with three large branches representing Archaea, Bacteria, and Eukarya. These three branches would represent different:

A)domains.
B)genera.
C)species.
D)kingdoms.
E)phyla.

Question 24

The _____ level of the taxonomic hierarchy is more inclusive than a family, but less inclusive than a class.

A)order
B)phylum
C)kingdom
D)genus
E)species

Question 25

Phylogenetic trees represent hypotheses about the evolutionary relationships among groups of organisms.

Question 26

The tips of the branches on a phylogenetic tree represent:

A)present-day groups or extinct taxa.
B)common ancestors.
C)analogies.
D)sister groups.
E)homologies.

Question 27

The evolutionary history of a group of organisms is called a:

A)phylogeny.
B)taxonomy.
C)morphology.
D)fossil.

Question 28

Which of the following represents the MOST informative evolutionary history of a taxon?

A)monophyletic groups
B)paraphyletic groups
C)polyphyletic groups
D)derived groups
E)All of these choices are correct.

Question 29

Imagine that you are chatting with one of your friends. He states that reptiles are obviously a monophyletic group, as this group contains all of the organisms (outside of fish) that possess scales. This statement is:
, as monophyletic groups are based solely on the morphological characteristics of their included species.
B)true, as the reptile group includes all of the organisms derived from a common ancestor on the phylogenetic tree.
C)false, as reptiles are a polyphyletic group, much like birds and bats.
D)false, as reptiles are a paraphyletic group; this group does not include birds, even though birds share a common ancestor with reptiles.

Question 30

The nodes on a phylogenetic tree represent:

A)common ancestors.
B)descendant lineages.
C)sister groups.
D)present-day groups.
E)homologies.

Question 31

The phylogeny below shows: Photo sources: (left to right) Zoonar/K. Jorgensen/age fotostock; S Sailer/A Sailer/age fotostock; J & C Sohns/age fotostock; Michael Dick/ Animals Animals-Earth Scenes; FLPA/Jurgen & Christi/age fotostock; Yellow Dog Productions/Getty Images.

A)a hypothesis about the evolutionary relationships of the apes.
B)proof of the evolutionary relationships between humans and chimps.
C)chimps gave rise to humans.

Question 32

The order of groups along the tips of a phylogenetic tree indicates how closely those groups are related.

Question 33

According to Figure 23.2 below, the most recent common ancestor of a bird and a turtle is also the most recent common ancestor of a bird and which other group?

A)snake
B)human
C)crocodile
D)frog
E)None of the answer options is correct.

Question 34

If two organisms are in the same class, then which of the following must also be TRUE?

A)They are in the same phylum.
B)They are in the same family.
C)They are in the same genus.
D)They are in the same order.
E)None of the answer options is correct.

Question 35

A grouping that includes an ancestor and some, but not all, of the descendants of that ancestor is described as:

A)paraphyletic.
B)polyphyletic.
C)monophyletic.
D)convergent.
E)analogous.

Question 36

Imagine that a taxonomist is provided with several flashcards on which the names of different species are written. She would likely organize these flashcards to construct a phylogenetic tree. To do this, would she pay attention to which species belong to which genus or class?

A)yes
B)no

Question 37

A taxon that includes a single common ancestor and all its descendants is a _____ group.

A)monophyletic
B)paraphyletic
C)polyphyletic

Question 38

Which of the following statements is TRUE regarding a phylogenetic tree?

A)Phylogenetic trees could be considered physical representations of hypotheses-those that seek to establish the evolutionary relationships between different organisms.
B)Given the sheer number of prokaryotic and eukaryotic species on Earth, it is impossible to create a phylogenetic tree encompassing all of these organisms.
C)Phylogenetic trees are constructed based solely on the morphological characteristics of species; sequence similarities among different organisms are only evaluated by taxonomists.
D)Within a phylogenetic tree, the order of groups located at the tree tips-not the nodes within a tree-determines sister group relationships.
E)Phylogenetic trees only depict the evolutionary relationships between different classes; relationships among different species within the same genus are not illustrated in such trees.

Question 39

Of the following taxonomic categories, which is the MOST inclusive?

A)class
B)genus
C)species
D)family
E)order

Question 40

Two taxa that are more closely related to each other than to any other taxon are called _____ groups.

A)sister
B)paraphyletic
C)homologous
D)polyphyletic
E)analogous

Question 41

When comparing trees with various hypotheses of evolutionary relationships among a group of animals, the tree with _____ changes would be the preferred candidate.

A)fewest
B)three
C)four
D)most

Question 42

Examine the following table of characters in four different species of flower. Based on the matrix, Derek concludes that species A is sister to the remaining three species. Wilma, in contrast, argues that species D is sister to all other species. Who is CORRECT? $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$

A)Derek is correct, as the tree that puts A as sister to all other species is the most parsimonious.
B)Wilma is correct, as the tree that puts D as sister to all other species is the most parsimonious.
C)Neither, because the most parsimonious tree puts species B as sister to all others.
D)We can't decide from the information given as trees with species A, B, or D as sister to all other species are equally parsimonious.

Question 43

Characters that are similar because of descent from a common ancestor are:

A)homologous.
B)analogous.
C)examples of convergent evolution.
D)synapomorphies.

Question 44

You are given a fossil and told that approximately 3% of the ¹⁴C originally in the sample is still there. How old is your sample? (Note that ¹⁴C has a half-life of 5730 years).

A)approximately 11,500 years
B)approximately 17,000 years
C)approximately 23,000 years
D)approximately 29,000 years

Question 45

Examine the following table of characters in four different species of flower. Based on the matrix, which character defines a synapomorphy shared by species A and B? $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$

A)presence of sepals
B)number of petals
C)arrangement of petals
D)number of carpels

Question 46

Streamlined bodies are common in many aquatic organisms: Dolphins, tuna, penguins, and sharks are all organisms that have streamlined bodies that reduce friction and drag. Body shape in each of these organisms would be considered an:

A)analogous character.
B)homologous character.
C)similar character.
D)natural character.

Question 47

You are given a character matrix for four different taxa showing character states for eight different morphologic characters. How many alternative phylogenetic hypotheses can be generated with the four taxa?

A)3
B)12
C)15
D)24
E)32

Question 48

Which molecular detail can be used to construct phylogenetic histories?

A)individual nucleotides
B)amino acids
C)RNA
D)All of these choices are correct.

Question 49

Examine the following table of characters in four different species of flower. Based on the character matrix, which is MOST likely an ancestral trait for the group of species? $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$

A)presence of sepals
B)number of petals
C)arrangement of petals
D)number of carpels

Question 50

Excluding the outgroup, taxon A, how many equivalent sister-group relationships are depicted between the two phylogenies given below?

A)one
B)two
C)three
D)four
E)There are no equivalent sister-taxa shown between the two phylogenies.

Question 51

Characters that are similar because of descent from a common ancestor are _____; characters that are similar due to convergent evolution are _____.

A)homologous; analogous
B)analogous; homologous

Question 52

Phylogenetic trees can be built using:

A)anatomical data.
B)molecular data.
C)visible characteristics only.
D)anatomical data or molecular data.

Question 53

To be useful for phylogenetic reconstruction, a taxonomic character must exhibit which of the following properties?

A)It must vary among the taxa being analyzed, but not within individual taxa.
B)It must have a genetic basis.
C)It must be anatomical.
D)It must be molecular (DNA or protein).
E)None of the other answer options is correct.

Question 54

The same intron was sequenced from five different taxa (taxa A-E) whose evolutionary relationships are disputed. The data matrix given shows six variable sites (1-6, left column) in the DNA sequences obtained from each of the five species. Taxon A serves as the outgroup for this analysis. $\begin{array}{|c|c|c|c|c|c|}\hline & \operatorname{taxon} \mathrm{A} & \operatorname{tax} n \mathrm{~B} & \operatorname{tax} n \mathrm{C} & \operatorname{taxon} \mathrm{D} & \operatorname{taxon} \mathrm{E} \\\hline 1 & \mathrm{~A} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} \\\hline 2 & \mathrm{C} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\\hline 3 & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{A} \\\hline 4 & \mathrm{~A} & \mathrm{~A} & \mathrm{~T} & \mathrm{~A} & \mathrm{~T} \\\hline 5 & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} & \mathrm{C} \\\hline 6 & \mathrm{~A} & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} \\\hline\end{array}$ Which of the phylogenies below explains the relatedness between these taxa with the FEWEST evolutionary steps?

A)phylogeny I
B)phylogeny II
C)Both phylogenetic trees have the same number of evolutionary steps.

Question 55

You find a fossil that you think is about 350 million years old. You decide to use ²³⁵U to date a volcanic ash bed just below the key specimen. If you are correct, what approximate percentage of the original ²³⁵U would you expect to remain in your sample?

A)0%
B)25%
C)50%
D)75%
E)100%

Question 56

While taking a hike in the forest, you find some fossils in layers of sedimentary rocks whose age, you later find out, is said to cover a span of 100-400 million years. You decide to send the fossils out for analysis to a company that dates rocks by radioactive decay, and, some weeks later, receive a report informing you that a volcanic ash bed associated with one of the fossils has a 1:1 ratio of ²³⁵U: ²⁰⁷Pb. Do these data support or refute the assumed age of the rocks in which the fossil was found? (Note: The half-life of ²³⁵U is about 704 million years.)

A)Yes, because the rock layers are less than 704 million years old.
B)Yes, because the ratio of ²³⁵U to ²⁰⁷Pb represents one half-life and that would be approximately 350 million years old.
C)No, because the ratio of ²³⁵U to ²⁰⁷Pb represents one half-life and that would be about 700 million years old.
D)No, because the rock layers are less than 704 million years old.

Question 57

When selecting among multiple possible phylogenetic trees that fit our data, we commonly use the principle of _____, which means we choose the _____ possible hypothesis. In phylogenetic analysis, that means selecting the tree that represents the _____ evolutionary changes or mutations.

A)parsimony; simplest; fewest
B)parsimony; simplest; most
C)parsimony; most; likely
D)phylogenetics; simplest; fewest
E)phylogenetics; simplest; most

Question 58

With the advent of tools to incorporate molecular data, phylogenetic analysis can be used to:

A)reconstruct the evolutionary history of a group of organisms over millions of years.
B)track the spread of a pathogen, such as a fungus or virus, from place to place.
C)identify the origin of invasive pest species.
D)track shipments of endangered species or their products (such as elephant ivory or bushmeat).
E)All of these choices are correct.

Question 59

You discover a new species of ape that is more closely related to gorillas than to any other species of ape, but walks upright. How would you change the phylogeny below? Photo sources: (left to right) Zoonar/K. Jorgensen/age fotostock; S Sailer/A Sailer/age fotostock; J & C Sohns/age fotostock; Michael Dick/ Animals Animals-Earth Scenes; FLPA/Jurgen & Christi/age fotostock; Yellow Dog Productions/Getty Images.

A)I would not change the phylogeny at all because only molecular data are considered when studying evolutionary relationships.
B)I would not change the phylogeny at all until a fossil of the new species is found because fossil evidence is a required component of the data set.
C)I would group gorillas with humans based on the synapomorphy (shared trait)of upright stance.
D)I would branch the gorilla lineage and add the new species sister to gorillas.

Question 60

The same intron was sequenced from five different taxa (taxa A-E) whose evolutionary relationships are disputed. The data matrix given shows six variable sites (1-6 in left column) in the DNA sequences obtained from each of the five species. Taxon A serves as the outgroup for this analysis. $\begin{array}{|c|c|c|c|c|c|}\hline & \operatorname{taxon} \mathrm{A} & \operatorname{tax} n \mathrm{~B} & \operatorname{tax} n \mathrm{C} & \operatorname{taxon} \mathrm{D} & \operatorname{taxon} \mathrm{E} \\\hline 1 & \mathrm{~A} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} \\\hline 2 & \mathrm{C} & \mathrm{T} & \mathrm{T} & \mathrm{T} & \mathrm{T} \\\hline 3 & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{A} \\\hline 4 & \mathrm{~A} & \mathrm{~A} & \mathrm{~T} & \mathrm{~A} & \mathrm{~T} \\\hline 5 & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} & \mathrm{C} \\\hline 6 & \mathrm{~A} & \mathrm{~A} & \mathrm{C} & \mathrm{A} & \mathrm{C} \\\hline\end{array}$ Which of the phylogenies below explains the relatedness between these taxa with the FEWEST evolutionary steps?

A)phylogeny I
B)phylogeny II
C)Both phylogenetic trees have the same number of evolutionary steps.

Question 61

Traits that are similar in two species as a result of common ancestry are referred to as:

A)homologous.
B)analogous.
C)convergent.
D)derived.
E)ancestral.

Question 62

When several possible phylogenetic trees can be produced from a data set, the MOST parsimonious tree is the one that shows the:

A)smallest number of evolutionary changes.
B)largest number of nodes.
C)largest number of analogous characteristics.
D)smallest number of synapomorphies.
E)smallest number of branches.

Question 63

Imagine that a researcher has created two possible phylogenetic trees for a group of organisms-one that hypothesizes that five character changes occurred in a given group, and one that predicts only two character changes occurred in the same group. If the researcher wants to choose a phylogenetic tree based on parsimony, she will pick the phylogenetic tree with two character changes as her working hypothesis.

Question 64

Both analogies and homologies are always used to create phylogenetic trees. In fact, analogies often provide more information regarding the evolutionary relationships between different species than do homologies.

Question 65

In order to be useful for constructing a phylogeny, a character must:

A)have a genetic basis.
B)vary within a species.
C)have only one state.
D)show the same state across several species.
E)All of these choices are correct.

Question 66

Phylogenetic trees can be used to infer character states of extinct organisms.

Question 67

Which of the following character states would be MOST helpful in identifying sister groups?

A)character states that occur only within a single species
B)character states that occur in all descendants of a distant common ancestor
C)homologies that are only found in some, but not all, the members of a single group
D)analogies found in organisms belonging to different groups, and which do not share a common ancestor

Question 68

Traits that are shared by more than one member of a group because of common ancestry are known as:

A)synapomorphies.
B)homologies.
C)analogies.
D)cladistics.
E)alternative character states.

Question 69

Seals and penguins both have streamlined body forms that allow them to move through water efficiently. This similarity in body shape is MOST likely the result of:

A)convergent evolution.
B)shared ancestry.
C)homology.
D)phylogeny
E)cladistics

Question 70

Examine the following table of characters in four different species of flower. Based on the matrix, which character would be the least informative for resolving phylogenetic relationships between the species? $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$

A)presence of sepals
B)number of petals
C)arrangement of petals
D)number of carpels

Question 71

Examine the following table of characters in four different species of flower. $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$ Do the characters presence of sepals and number of petals together provide a unique solution to the question of phylogenetic relationships among species A, B, C, and D?

A)yes
B)no

Question 72

To conduct a phylogenetic analysis, an outgroup is needed in order to:

A)decide which characters are analogous and which are homologous.
B)determine which character states are ancestral and which are derived.
C)determine which characteristics to include in our analysis.
D)decide which molecular data to use.
E)All of these choices are correct.

Question 73

Phylogenetic reconstruction based on shared derived characters is called:

A)synapomorphy.
B)cladistics.
C)monophyly.
D)taxonomy.

Question 74

Only homologous characters are useful in constructing phylogenetic trees.

Question 75

Which of the following statements is TRUE regarding phylogenetic trees?

A)Phylogenetic trees are only constructed based on morphological data; molecular data (even for viruses)is never used in the construction of such trees.
B)As synapomorphies only occur for morphological characters, molecular sequence synapomorphies cannot be used to construct phylogenetic trees.
C)Both morphological and molecular synapomorphies can be used to construct phylogenetic trees.
D)Phylogenetic trees based on molecular sequence data always assume that the rate of evolution varies between different organisms.
E)Phylogenetic trees are always constructed based on morphological or molecular sequence data-never both.

Question 76

The specific types of homologies used to develop phylogenies are shared derived characters or:

A)sister groups.
B)convergent characteristics.
C)synapomorphies.
D)parsimonious branches.

Question 77

Compared with more distantly related taxa, the DNA sequences of two closely related taxa are expected to show:

A)fewer differences because mutation rates are usually relatively constant and recently diverging species have had less time to accumulate differences.
B)fewer differences because mutation rates slow down after speciation events so that recently diverging species have fewer mutations.
C)fewer differences because mutation rates are highly variable and it is just by chance that recently diverging species accumulate fewer differences in DNA sequences.
D)more differences because mutation rates are relatively constant and recently diverging species have had more time to accumulate differences.
E)more differences because mutation rates accelerate during speciation events, leading to more changes in DNA sequences.

Question 78

Why might a phylogeny based only on molecular data show a different pattern of relationships than a phylogeny of the same taxa that is based only on morphological traits?

A)Gene sequences always provide more data than morphological traits.
B)Morphological analyses always provide more data because each morphological trait is the result of the expression of many genes.
C)The molecular data may be based on the analysis of introns, which aren't expressed and don't contribute to the evolutionary history of a group of taxa.
D)Some highly conserved genetic sequences can result in unrelated species appearing closely related in a molecular phylogeny, and not reflect the same pattern as the morphologic phylogeny.
E)Gene sequence changes may not result in morphological changes.

Question 79

Imagine that a scientist discovers a new, flying species of mammal that resembles a winged rabbit. What can the scientist say about this organism?

A)Without any further information, the scientist can say that bat wings and the wings of this new species are homologous.
B)If molecular sequence data show that bats and this new species share a common ancestor not shared by other mammals, the wings of these two species would be considered homologous.
C)If molecular sequence data show that bats and this new species do not share a common ancestor not shared by other mammals, the wings of bats and this new species would be considered homologous.
D)If molecular sequence data show that bats and this new species share a common ancestor not shared by other mammals, the wings of these two species would be considered analogous.
E)No data could support or disprove the hypothesis that the wings of bats and the new species are homologous.

Question 80

Examine the following table of characters in four different species of flower. $$\begin{array} { | l | c | c | c | c | } \hline & \text { Species A } & \text { Species B } & \text { Species C } & \text { Species D } \\\hline \begin{array} { l } \text { Presence of } \\\text { sepals }\end{array} & \text { yes } & \text { yes } & \text { yes } & \text { no } \\\hline \begin{array} { l } \text { Number of } \\\text { petals }\end{array} & \text { five } & \text { five } & \text { ten } & \text { ten } \\\hline \begin{array} { l } \text { Arrangement of } \\\text { petals }\end{array} & \text { whorled } & \text { whorled } & \text { whorled } & \text { whorled } \\\hline \begin{array} { l } \text { Number of } \\\text { carpels }\end{array} & \text { ten } & \text { ten } & \text { ten } & \text { five } \\\hline\end{array}$$ Which character would be MOST useful for identifying the sister group of species D?

A)presence of sepals
B)number of petals
C)arrangement of petals
D)number of carpels