Deck 4: Phylogeny and Evolutionary History

Question 1

Charles Darwin inferred the pattern of common ancestry without understanding the basis for heredity. However, if Darwin's theory of descent with modification is correct, then

A) DNA sequence similarity should reflect patterns of common ancestry inferred from other evidence.
B) DNA sequences will indicate the correct phylogeny, and other traits, such as morphology and anatomy, will be irrelevant to common ancestry.
C) the hereditary basis of a trait will not matter for understanding its evolutionary history.
D) common ancestry will be reflected in phylogenies only for traits that are determined by a single gene.

Answer 1

A

Question 2

What is different between a rooted and unrooted tree?

A) An unrooted tree indicates the common ancestor from which all species on the tree are derived.
B) Relationships on an unrooted tree are not experimentally testable.
C) Direction on a rooted tree indicates the passage of time.
D) Rooted trees are correct, whereas unrooted trees are incorrect.

Answer 2

C

Question 3

The study of phylogeny predominantly aims to

A) understand the branching relationships of populations as they give rise to descendant populations over time.
B) uncover evidence for natural selection.
C) provide a theoretical basis for Darwin's idea of a branching pattern of descent with modification.
D) classify organisms based on similarity.

Answer 3

A

Question 4

Based on the phylogenetic tree, which of the following two groups are most closely related?

A) turtles and snakes
B) ray-finned fishes and lobe-finned fishes
C) birds and crocodilians
D) mammals and snakes

Question 5

The unrooted phylogeny in the figure shows the relationships among proteobacteria. Which of the following would be true if the root were placed on the branch between nodes A and B?

A) C. violaceum is more closely related to P. diminuta than it is to E. coli.
B) Z. ramigera is more closely related to E. coli than it is to C. violaceum.
C) P. diminuta is more closely related to Z. ramigera than it is to E. coli.
D) E. coli is more closely related to P. diminuta than it is to Z. ramigera.

Question 6

In the figure, what does the lower interior node in each figure represent?

A) the individual that gave rise to birds and crocodilians
B) the most recent common ancestor of birds and crocodilians
C) the most recent common ancestor to all tetrapods
D) a population that would result from the hybridization of birds and crocodilians

Question 7

Which of the following statements about pedigrees and phylogenies is true?

A) Both show the splitting and the recombining of branches or lineages over time.
B) Pedigrees tell us about the ancestry of individuals; phylogenies tell us about the ancestry of populations.
C) Both expand as one looks backward in time.
D) The nodes in a pedigree represent populations; the nodes in a phylogeny represent individuals.

Question 8

What does the study of phylogeny allow us to understand?

A) evolutionary relationships among organisms, but not major events in evolutionary history
B) major events in evolutionary history, but not evolutionary relationships among organisms
C) evolutionary relationships among organisms and major events in evolutionary history
D) neither evolutionary relationships among organisms nor major events in evolutionary history

Question 9

The study of phylogeny rests on our observation of characters of organisms, which may include all of the following EXCEPT

A) anatomical features.
B) developmental processes.
C) DNA sequences.
D) Linnaean taxonomy.

Question 10

German biologist Willi Hennig (1913-1976) established the modern approach to classification in his book Phylogenetic Systematics, where he described how to classify organisms according to which of the following?

A) Linnaean nomenclature
B) their morphology and where they are located
C) convergent evolution
D) their evolutionary histories

Question 11

The goal of Linnaean taxonomy and the resulting system of scientific nomenclature (convention for naming organisms) was to

A) classify biological diversity.
B) explain the evolutionary history of organisms.
C) group organisms based on shared genetic traits.
D) please the Chinese emperor.

Question 12

Based on the figure, which of the following statements is true?

A) Fish are not a monophyletic group.
B) Amphibians are not a monophyletic group.
C) Tetrapod vertebrates are not a monophyletic group.
D) Lampreys are not a monophyletic group.

Question 13

What is the difference between cladograms, phylograms, and chronograms?

A) the rooting of the trees
B) how polyphyletic and paraphyletic groups are determined
C) what branch lengths represent
D) the number of homologous traits

Question 14

A paraphyletic group contains

A) the group's most recent common ancestor but not all of its descendants.
B) neither the common ancestor of all of its members nor all descendants of that ancestor.
C) all descendants of the group's most recent common ancestor and no other members.
D) unrelated members.

Question 15

On a phylogram, what do branch lengths represent?

A) the passage of time
B) the amount of evolutionary change
C) how many speciation events have occurred
D) the rate of extinction

Question 16

Which of the following statements is true based on the phylogeny shown in the figure?

A) Rodents are members of the Eutheria and Carnivora clades.
B) Primates are members of the Eutheria and Mammalia clades.
C) Monotremata are members of the Eutheria and Mammalia clades.
D) Felidae are members are the Carnivora clade, but not the Theria clade.

Question 17

Based on the phylogenetic tree, which of the following is most closely related to mammals?

A) turtles
B) amphibians
C) lampreys
D) lobe-finned fishes

Question 18

In the figure, the shrublike or treelike species are circled in black, and the remaining species are herbaceous. Based on the figure, which of the following statements is true?

A) For the herbaceous species, the branch lengths tend to be shorter, and the rates of sequence change more slowly.
B) For the herbaceous species, the branch lengths tend to be longer, and the rates of sequence change more slowly.
C) For the herbaceous species, the branch lengths tend to be longer, and the rates of sequence change faster.
D) For the herbaceous species, the branch lengths tend to be shorter, and the rates of sequence change faster.

Question 19

If the tree shown in the figure were rooted at the point labeled B, which of the following would be true?

A) 1, 2, and 3 form a monophyletic group.
B) 3, 4, and 5 form a monophyletic group.
C) 2, 3, 4, and 5 form a monophyletic group.
D) 3 and 4 form a monophyletic group.

Question 20

Which of the following is Carolus Linnaeus (1707-1778) responsible for?

A) categorizing organisms based on shared derived traits
B) understanding that an evolutionary process of branching descent with modification would generate nested hierarchies of similarity among organisms
C) having the insight that organisms can be organized into a hierarchical system of classification without having a theoretical explanation for why these patterns should exist
D) being the first to recognize that to make sense of the world with all of its variation, we should categorize the organisms in it.

Question 21

Aposematic, or warning, coloration in poison frogs was found by Juan Santos and colleagues to be polyphyletic. What does this indicate about aposematic coloration?

A) It arose in the common ancestor of these frogs.
B) It is homologous.
C) It is the result of convergent evolution.
D) It is an exaptation.

Question 22

The figure shows the phylogeny of snakes, Gila monsters, and their relatives. If venom production in snakes and Gila monsters is a homologous trait, would you expect to find venom production in other lizards and iguanas?

A) No. Gila monsters share a common ancestor with other lizards and iguanas, but not with snakes; therefore, the presence of venom production in snakes and Gila monsters does not allow us to hypothesize about venom production in other species.
B) No. Homologous traits do not evolve easily; therefore, we would not expect other species to have evolved venom production.
C) Yes. If venom is homologous, then the common ancestor of snakes and Gila monsters would have produced venom and it is likely that the other descents of that ancestor would also produce venom.
D) Yes. Because snakes and Gila monsters independently evolved venom production, it seems likely that other lizards and iguanas would also be able to evolve venom production.

Question 23

The figure shows (A) a cladogram of primates and (B) a phylogram of primate lentiviruses. What do the branch lengths in each phylogeny represent?

Question 24

Examine the tree of life of all known groups of living organisms in the figure. Describe the relationship of animals to the rest of life on Earth.

Question 25

Analogous traits are found in two or more species because

A) some evolutionary process (usually natural selection) has independently fashioned similar traits in each species.
B) those traits have been inherited from a common ancestor.
C) hybridization between the species passes the trait on to both.
D) evolution by natural selection requires heritable variation.

Question 26

Phylogenies can be used to distinguish homologous traits from analogous traits. How can this distinction help to generate hypotheses about the role of natural selection in shaping the evolution of a trait?

Question 27

The figure shows where tetrapod limbs evolved ("Origin of tetrapod vertebrates") in the evolutionary history of animals. Based on this figure, in which limbless organisms would you expect to find vestigial limbs?

A) jellyfish
B) annelid worms
C) fishes
D) snakes

Question 28

Both the process of reconstructing phylogenies and mapping traits onto phylogenies can allow scientists to generate hypotheses. What kind of hypotheses does each of these processes generate?

Question 29

Do the five trees shown in the figure represent the same or different relationships among the taxa numbered 1-4? Explain your answer.

Question 30

Which of the following is true of both analogous and homologous traits?

A) Both can be used as evidence for Darwin's theory of evolution by natural selection.
B) Both provide evidence of shared ancestry.
C) Both reveal that natural selection often generates similar solutions to similar problems.
D) Both indicate the inheritance of acquired traits.

Question 31

By mapping a given trait on a phylogenetic tree that we have already constructed using other data, we can

A) generate hypotheses about when and how this trait evolved.
B) create a pedigree for the trait.
C) test for polytomies in this trait.
D) confirm the presence or absence of this trait in species for which we are lacking observational data.

Question 32

The figure shows a hypothesis for the evolution of visual opsins in tetrapods. At the tips, each triangle represents a particular visual pigment found in a modern tetrapod. Along ancestral branches, the hypothesized evolutionary history of these opsins are shown. Which of the following is true of this evolutionary hypothesis?

A) Squamate reptiles and birds have maintained the ancestral opsins.
B) Humans have lost a single opsin relative to the tetrapod ancestor.
C) New world primates lost two opsins, but then gained a new one.
D) Opsins have been gained and lost in every tetrapod lineage.

Question 33

A trait that is similar in one or more species even though it was not present in their common ancestor is called a

A) homology.
B) synapomorphy.
C) homoplasy.
D) symplesiomorphy.

Question 34

As shown in the figure, suppose a population splits into two descendant populations prior to the evolution of dark coloration, then splits again after the evolution of dark coloration found in Taxa 1 and 2. Which of the following terms best describes the dark coloration trait in this situation?

A) homoplasy
B) analogy
C) synapomorphy
D) symplesiomorphy

Question 35

Describe the two primary uses of traits in the study of phylogeny.

Question 36

The figure shows the coloration of populations of lizards and mice that live in various habitats. The differences in coloration among the three mice populations (assuming they share a recent common ancestor) are due to _______, whereas the similarity between the lizards and mice that live in the same habitat is due to _______.

A) natural selection; shared ancestry
B) monophyletic groups; polyphyletic groups
C) divergent evolution; convergent evolution
D) adaptation; exaptation

Question 37

Based on the figure, draw three rooted trees that would result from rooting at each of the nodes (A, B, and C) indicated by the labeled dots.

Question 38

Although they serve no known current functions, vestigial traits may persist in some organisms for all of the following reasons EXCEPT that

A) the trait is not costly to the organism.
B) the trait has some function that we have not identified.
C) there is some natural selection against the trait, and it is on its way out-eventually it will be lost.
D) natural selection cannot act to eliminate traits.

Question 39

Using the partial phylogeny of mammals in the figure, name one monophyletic group of species, one polyphyletic group, and one paraphyletic group.

Question 40

Homologous traits are found in two or more species because

A) some evolutionary process (usually natural selection) has independently fashioned similar traits in each species.
B) those traits have been inherited from a common ancestor.
C) hybridization between the species passes the trait on to both.
D) evolution by natural selection requires heritable variation.

Question 41

Assume you are an evolutionary biologist who is using coat coloration in several closely related species of mice to reconstruct their evolutionary history. You find that the coat color trait is symplesiomorphic. Why is this a problem for making inferences, and what can you do to help better resolve the species' evolutionary relationships?

Question 42

Imagine that you are studying a coat color in mice, with two forms of a trait divergent evolution of coat color. Explain your answer.

Question 43

The figure shows two hypotheses about evolutionary relationships among aquatic birds. The phylogeny in (A) is based on data from morphological characters and in (B) from DNA sequence data. What is the reason for the differences between these phylogenies? What could you do to resolve the differences?

Question 44

The tree in the figure shows the states of two characters; in the left column the trait is either A or B, and in the right column it is either R or S. This tree currently has several unresolved polytomies. Based on the data in this figure, draw a tree that resolves two of the polytomies and explain how the data support these relationships.

Question 45

Consider a species of mouse in which the coat color of populations change from light (the ancestral state) to dark (the derived state) over evolutionary time. Using this example, draw an evolutionary tree to illustrate each of the following evolutionary conditions, where dark coat color is a:
A. synapomorphy,
B. homoplasy, and
C. symplesiomorphy.

Question 46

Vestigial traits are those that have no known current function but appear to have been important in the evolutionary past. There are at least three possible explanations for why vestigial traits are found. Explain each of these possibilities, and describe an experiment you could perform to distinguish between these explanations for a particular vestigial trait.

Question 47

Give an example of two groups of organisms that share a trait due to shared ancestry, and contrast this with an example of organisms that share a trait but not because of shared ancestry. What are each of these types of shared traits called? Explain the evolutionary processes that resulted in the similarities in each example.