Deck 25: Phylogenies and the History of Life

Question 1

We know the streamlined bodies shown in the accompanying figure are examples of homoplasy. If the following groups also had streamlined bodies, which of the groupings would give the most support to this body type being homologous?

A) lizards and elephants
B) pterosaurs, dinosaurs, and birds
C) synapsids, monotremes, marsupials, rodents, and primates
D) lizards, pterosaurs, dinosaurs, birds, synapsids, monotremes, marsupials, rodents, and primates
E) elephants only

Answer 1

D

Question 2

The approach to estimating phylogenetic trees is most like the approach of which species concept?

A) morphological species concept
B) biological species concept
C) phylogenetic species concept
D) subspecies concept

Answer 2

C

Question 3

Use the following tree to answer the question below. Which of the following trees, if any, depicts the same relationship among species as shown above?

A)

B)

C)

D) None of the above.

Answer 3

C

Question 4

The term "homoplasy" is most applicable to which of the following features?

A) the legless condition found in various lineages of extant lizards
B) the five-digit condition of human hands and bat wings
C) the β hemoglobin genes of mice and of humans
D) the fur that covers Australian moles and North American moles
E) the bones of bat forelimbs and the bones of bird forelimbs

Question 5

Which of the following statements is TRUE about a phylogeny, as represented by a phylogenetic tree?
I) Descendant groups (branches) from the same node do not share any derived characters.
II) A monophyletic group can be properly based on convergent features.
III) The ancestral group always displays all the synapomorphies of the descendant species.

A) only I
B) only II
C) only III
D) I, II, and III
E) none; not I, II, or III

Question 6

Considering the phylogenetic trees above as strictly hypothetical and applying the principle of parsimony to the trait "ability to fly," which of the two phylogenetic trees shown is better?

A) Tree 1
B) Tree 2
C) Both trees are equally parsimonious.
D) Since the trees show different evolutionary relationships, you cannot determine which is more parsimonious.

Question 7

Some beetles and flies have antler-like structures on their heads, much like male deer do. The existence of antlers in beetle, fly, and deer species with strong male-male competition is an example of ________.

A) convergent evolution
B) a synapomorphy
C) homology
D) parsimony

Question 8

Your professor wants you to construct a phylogenetic tree of orchids. She gives you tissue from seven orchid species and one lily. What is the most likely reason she gave you the lily?

A) to serve as an outgroup
B) to see if the lily is a cryptic orchid species
C) to see if the lily and the orchids show all the same shared derived characters (synapomorphies)
D) to demonstrate likely homoplasies

Question 9

Which of the following is an example of homoplasy?

A) fur in bears and seals
B) cell walls in plants and fungi
C) chlorophyll in flowering plants and algae
D) scales in snakes and lizards

Question 10

Use the following table to answer the question(s) below.
What conclusion is apparent from the data in the accompanying table?

A) Land animals have more Hox genes than do those that live in water.
B) All bilaterian phyla have had the same degree of expansion in their numbers of Hox genes.
C) Acoel flatworms should be expected to contain seven Hox genes.
D) The expansion in number of Hox genes throughout vertebrate evolution cannot be explained merely by three duplications of the ancestral vertebrate Hox cluster.
E) Extant insects all have seven Hox genes.

Question 11

Both ancestral birds and ancestral mammals shared a common ancestor that was a terrestrial vertebrate. Today, penguins (which are birds) and seals (which are mammals) have forelimbs adapted for swimming. What term best describes the relationship of the bones in the forelimbs of penguins and seals, and what term best describes the flippers of penguins and seals?

A) homology; homology
B) homoplasy; homology
C) homology; homoplasy
D) homoplasy; homoplasy

Question 12

Given that phylogenies are based on shared derived characteristics, which of the following traits is useful in generating a phylogeny of species W, X, Y, and Z?

A) Trait 1
B) Trait 2
C) Trait 3
D) Traits 1, 2, and 3

Question 13

Members of two different species possess a similar-looking structure that they use in a similar way to perform about the same function. Which of the following would suggest that the relationship more likely represents homology instead of convergent evolution?

A) The two species live at great distance from each other.
B) The two species share many proteins in common, and the nucleotide sequences that code for these proteins are almost identical.
C) The structures in adult members of both species are similar in size.
D) Both species are well adapted to their particular environments.

Question 14

What must be TRUE of any organ described as vestigial?

A) It must be homoplasic to some feature in an ancestor.
B) It must be homologous to some feature in an ancestor.
C) It must be both homologous and homoplasic to some feature in an ancestor.
D) It need be neither homologous nor homoplasic to some feature in an ancestor.

Question 15

Ichthyosaurs, now extinct, were aquatic reptiles with dorsal fins and tails, similar to those of fish. Their most recent ancestors were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are ________.

A) homologous structures
B) adaptations to different environments
C) adaptations to a common environment and examples of convergent evolution
D) adaptations to a common environment and homologous structures

Question 16

All things being equal, which of these is the most parsimonious explanation for the change in the number of Hox genes from the last common ancestor of insects and vertebrates to ancestral vertebrates, as shown in the table above?

A) The occurrence of seven independent duplications of individual Hox genes.
B) The occurrence of two distinct duplications of the entire seven-gene cluster, followed by the loss of one cluster.
C) The occurrence of a single duplication of the entire seven-gene cluster.
D) Two distinct duplications of a three-gene cluster of Hox genes, followed by an independent duplication of an individual Hox gene.

Question 17

Two competing hypotheses to account for the increase in the number of Hox genes from the last common ancestor of bilaterians to the last common ancestor of insects and vertebrates are: (1) a single duplication of the entire four-gene cluster, followed by the loss of one gene, and (2) three independent duplications of individual Hox genes. To prefer the first hypothesis on the basis of parsimony requires the assumption that ________.

A) the duplication of a cluster of four Hox genes is equally likely to the duplication of a single Hox gene
B) there is an actual process by which individual genes can be duplicated
C) genes can exist in spatial groupings called clusters
D) clusters of genes can undergo disruption, with individual genes moving to different chromosomes during evolution

Question 18

Which of the following would be useful in creating a phylogenetic tree of a vertebrate taxon?
I) morphological data from fossil species
II) genetic sequences from living species
III) behavioral data from living species

A) I
B) II
C) III
D) I, II, and III
E) none; not I, II, or III

Question 19

Which of the following statements best describes the rationale for applying the principle of parsimony in constructing phylogenetic trees?

A) Parsimony allows the researcher to "root" the tree.
B) Similarity due to common ancestry should be more common than similarity due to convergent evolution.
C) The molecular clock validates the principle of parsimony.
D) The outgroup roots the tree, allowing the principle of parsimony to be applied.

Question 20

In the accompanying phylogenetic trees, numbers represent species and the same species are shown in both trees. Which two species are represented as sister species in Tree 2 but are not shown as sister species in Tree 1?

A) 1 and 2
B) 2 and 3
C) 3 and 4
D) 4 and 5
E) 5 and 6

Question 21

Which of the following is TRUE of all horizontally oriented phylogenetic trees, where time advances to the right?

A) Each branch point represents a point in absolute time.
B) Organisms represented at the base of such trees are descendants of those represented at higher levels.
C) The fewer branch points that occur between two taxa, the more divergent their DNA sequences should be.
D) The common ancestor represented by a branch point farther right existed more recently in time than the common ancestors represented at branch points located farther to the left.
E) The more branch points there are, the fewer taxa are likely to be represented.

Question 22

To apply parsimony to constructing a phylogenetic tree, ________.

A) choose the tree that assumes all evolutionary changes are equally probable
B) choose the tree in which the branch points are based on as many shared derived characters as possible
C) base phylogenetic trees only on the fossil record, as this provides the simplest explanation for evolution
D) choose the tree that represents the fewest evolutionary changes, either in DNA sequences or morphology
E) choose the tree with the fewest branch points

Question 23

Which of the following organisms would be most likely to fossilize?

A) a rare worm
B) a common worm
C) a rare squirrel
D) a common squirrel

Question 24

In plant communities today, leaf morphology is correlated with mean annual temperature, so paleobotanists use fossil leaf morphology to estimate the mean annual temperature of paleoclimates. However, the angiosperm fossil record contains an overabundance of samples fossilized near lakes or rivers where vines are especially common. Since vine leaves have a somewhat different association with temperature, use of data from vine-rich locations leads to mean average temperature estimates that are lower than actual recorded temperatures in modern plant communities. This potential bias in paleobotanical climate estimates is due to which type of bias in the fossil record? (R. J. Burnham, N. C. A. Pitman, K. R. Johnson, and P. Wilf. 2001. Habitat-related error in estimating temperature from leaf margins in a humid tropical forest. American Journal of Botany 88:1096-1102.)

A) taxonomic bias
B) temporal bias
C) habitat bias
D) abundance bias

Question 25

Which of these four gene parts should allow the construction of the most accurate phylogenetic tree, assuming that this is the only part of the gene that has acted as a reliable molecular clock?

A) Intron I
B) Exon I
C) Intron VI
D) Exon V

Question 26

The best classification system is that which most closely ________.

A) unites organisms that possess similar morphologies
B) conforms to traditional, Linnaean taxonomic practices
C) reflects evolutionary history
D) reflects the basic separation of prokaryotes from eukaryotes

Question 27

Which of the following is the best explanation for the high degree of sequence homology observed in Exon I among these five species?

A) It is the most upstream exon of this gene.
B) Due to alternative gene splicing, this exon is often treated as an intron.
C) It codes for a polypeptide domain that has a crucial function.
D) These five species must actually constitute a single species.
E) This exon is rich in G-C base pairs; thus, it is more stable.

Question 28

The common ancestors of birds and mammals were very early (stem) amniotes, which almost certainly possessed three-chambered hearts (two atria, one ventricle). Birds and mammals, however, are alike in having four-chambered hearts (two atria, two ventricles). The four-chambered hearts of birds and mammals are best described as ________.

A) structural homologies
B) vestigial structures
C) homoplasies
D) the result of shared ancestry
E) molecular homologies

Question 29

Some molecular data place the giant panda in the bear family (Ursidae) but place the lesser panda in the raccoon family (Procyonidae). If the molecular data best reflect the evolutionary history of these two groups, then the morphological similarities of these two species is most likely due to ________.

A) the inheritance of acquired characteristics
B) sexual selection
C) inheritance of shared derived characters
D) possession of homoplasic (convergent) traits
E) possession of shared ancestral characters

Question 30

Phylogenetic trees constructed from evidence from molecular systematics are based on similarities in ________.

A) morphology
B) the pattern of embryological development
C) biochemical pathways
D) habitat and lifestyle choices
E) mutations to homologous genes

Question 31

Which value(s) would be required to calculate how long ago the most recent ancestor of ungulates lived?
I) the number of base pairs that differ among species in a certain genetic sequence
II) the total number of base pairs in the genetic sequence examined
III) the age of a fossil ancestor for calibration

A) I
B) II
C) III
D) I, II, and III

Question 32

For many years, scientists believed that almost all animal lineages burst into being during the Cambrian era (just after the end of the Precambrian super eon). However, there have been many recent findings of animal-like fossils and "trace fossils" (fossils of an animal-like organism's movement) from the late Precambrian. Which of the following best explains why it took so long to realize there was animal-like life in the Precambrian?

A) There were no animals in the Precambrian.
B) Animals from the late Precambrian had soft bodies.
C) There were many hard-shelled animals in the Cambrian.
D) The global climate was such that there was poor fossilization in the Precambrian.

Question 33

Regarding these sequence homology data, the principle of maximum parsimony would be applicable in ________.

A) distinguishing introns from exons
B) determining degree of sequence homology
C) selecting appropriate genes for comparison among species
D) inferring evolutionary relatedness from the number of sequence differences

Question 34

The question(s) below refer to the following table, which compares the % sequence homology of four different parts (two introns and two exons) of a gene that is found in five different eukaryotic species. Each part is numbered to indicate its distance from the promoter (for example, Intron I is the one closest to the promoter). The data reported for species A were obtained by comparing DNA from one member of species A to another member of species A.
Based on the tabular data, and assuming that time advances vertically, which phylogenetic tree is the most likely depiction of the evolutionary relationships among these five species?

A)

B)

C)

D)

Question 35

If you were using cladistics to build a phylogenetic tree of cats, which of the following would be the best outgroup?

A) lion
B) domestic cat
C) wolf
D) leopard
E) tiger

Question 36

Which of the following would be LEAST likely in the fossil record?

A) burrowing species
B) marine-dwelling species
C) marsh-dwelling species
D) desert-dwelling species

Question 37

Which statement represents the best explanation for the observation that the nuclear DNA of wolves and domestic dogs has a very high degree of sequence homology? Dogs and wolves ________.

A) have very similar morphologies
B) belong to the same order
C) are both members of the order Carnivora
D) share a very recent common ancestor

Question 38

If, someday, an Archaean cell is discovered with an rRNA sequence that is more similar to that of humans than the sequence of mouse rRNA is to that of humans, the best explanation for this apparent discrepancy would be ________.

A) homology
B) homoplasy
C) common ancestry
D) retro-evolution by humans
E) coevolution of humans and the Archaean cell

Question 39

When using a cladistic approach to systematics, which of the following is considered most important for classification?

A) shared ancestral characters
B) homoplasic ancestral characters
C) shared derived characters
D) the number of homoplasies
E) overall phenotypic similarity

Question 40

Which factor most likely caused animals and plants in India to differ greatly from species in nearby southeast Asia?

A) The species have become separated by convergent evolution.
B) The climates of the two regions are similar.
C) India is in the process of separating from the rest of Asia.
D) Life in India was wiped out by ancient volcanic eruptions.
E) India was a separate continent until 45 million years ago.

Question 41

Upon being formed, oceanic islands, such as the Hawaiian Islands, should feature what characteristic, leading to which phenomenon?

A) mass extinctions, leading to bottleneck effect
B) major evolutionary innovations, leading to rafting to nearby continents
C) a variety of empty ecological niches, leading to adaptive radiation
D) adaptive radiation, leading to founder effect
E) overcrowding, leading to rafting to nearby lands

Question 42

All of the following events can trigger an adaptive radiation EXCEPT ________.

A) an unusual event splitting a habitat, such as a severe hurricane
B) the evolution of a new morphological feature
C) the colonization of a new habitat
D) the extinction of competitors
E) Hox gene duplication events

Question 43

You are the lucky student of a wacky professor who develops a time machine. He asks if you will test it with him. You get in and there is an immediate glitch-the date readout fails so that when you land you are not sure what era you are in. Your professor begins to panic, but you see something that tells you are in the Cenozoic era. Which of the following could it be?

A) a rabbit eating a daisy
B) a water lily floating in a pond
C) masses of green ferns with dragonflies hovering above them
D) a forest of large tree ferns
E) a herd of huge long-necked sauropod dinosaurs

Question 44

Refer to the following information to answer the question below.
Which of the following is the most likely explanation for the modern-day distribution of dicynodont fossils? The dicynodonts were ________.

A) carnivores that traveled widely to find prey
B) evenly distributed throughout all of Pangaea
C) most abundantly distributed throughout Gondwana
D) amphibious and able to swim long distances

Question 45

Adaptive radiations can be a direct consequence of four of the following five factors. Select the exception.

A) vacant ecological niches
B) genetic drift
C) colonization of an isolated region that contains suitable habitat and few competitor species
D) evolutionary innovation
E) an adaptive radiation in a group of organisms (such as plants) that another group uses as food

Question 46

Which statement is most consistent with the hypothesis that the Cambrian explosion was caused by the rise of predator-prey relationships? The fossil record reveals an increased incidence of ________.

A) worm burrows
B) larger animals
C) organic material
D) fern galls
E) hard parts

Question 47

On the basis of their morphologies, how might Linnaeus have classified the Hawaiian silverswords? Linnaeus would have ________.

A) placed them all in the same species
B) classified them the same way that modern botanists do
C) placed more of them in different genera than modern botanists do
D) used evolutionary relatedness as the primary criterion for their classification

Question 48

Refer to the following information to answer the question below.
Which of the following statements is correct?

A) There are fossils of animals in geological strata that are older than the Cambrian.
B) Only fossils of microorganisms are found in geological strata older than the Cambrian.
C) The Cambrian explosion is evidence for the instantaneous creation of life on Earth.
D) The Cambrian explosion marks the appearance of filter-feeding animals in the fossil record.

Question 49

The question(s) below refer to the following paragraph.
Which of the following reasons would explain why the sediment core lacks fossils of dragonflies with 3-foot wingspans?
1) This particular sediment core includes the correct stratum, but the part of the stratum captured by the core lacks such fossils.
2) The sea was not present at this site during the time that 3-foot dragonflies existed.
3) Dragonflies have no hard parts, such as exoskeletons, to fossilize.
4) The sediments containing these fossils at this site may have been eroded away during a time when the sea had receded from this site.
5) Dragonflies are terrestrial; therefore, fossils of terrestrial organisms should not be expected in the sediments of seas.

A) 1 only
B) 3 only
C) 5 only
D) 2 or 4
E) 1, 2, or 4

Question 50

Approximately how far back in time does the fossil record extend?

A) 3.5 million years
B) 5.0 million years
C) 3.5 billion years
D) 5.0 billion years

Question 51

According to the theory of sea-floor spreading, oceanic islands, such as the Hawaiian Islands depicted in the accompanying figure, form as oceanic crustal plates move over a stationary "hot spot" in the mantle. Currently, the big island of Hawaii is thought to be over a hot spot, which is why it is the only one of the seven large islands that has active volcanoes. What should be TRUE of the island of Hawaii?
1) Scientists in search of ongoing speciation events are more likely to find them here than on the other six large islands.
2) Its species should be more closely related to those of nearer islands than to those of farther islands.
3) It should have a rich fossil record of terrestrial organisms.
4) It should have species that are not found anywhere else on Earth.
5) On average, it should have fewer species per unit surface area than the other six islands.

A) 1, 2, and 3
B) 1, 2, and 5
C) 1, 2, 3, and 4
D) 1, 2, 4, and 5
E) 2, 3, 4, and 5

Question 52

Whatever its ultimate cause(s), the Cambrian explosion is a prime example of ________.

A) mass extinction
B) evolutionary stasis
C) adaptive radiation
D) a large meteor impact

Question 53

You are the lucky student of a wacky professor who develops a time machine. He asks if you will test it with him. You get in and there is an immediate glitch-the date readout fails so that when you land you are not sure what era you are in. As your time machine lands, you see an unusual landscape before you. As you open the door, you realize you cannot breathe. You quickly shut the door, realizing you are in the ________.

A) Archaean eon
B) Anthropocene epoch
C) Cenozoic era
D) Mesozoic era

Question 54

The question(s) below refer to the following paragraph.
If arrows indicate locations in the column where fossils of a particular type (see key in the accompanying figure) first appear, then which core in the figure has the most accurate arrangement of fossils?

A) core A
B) core B
C) core C
D) core D

Question 55

To assign absolute dates to fossils in this sediment core, it would be most helpful if ________.

A) we knew the order in which the fossils occurred
B) the sediments had not been affected by underwater currents during their deposition
C) volcanic ash layers were regularly interspersed between the sedimentary strata
D) fossils throughout the column were equally spaced apart

Question 56

Which listing of geological periods is in the correct order, from oldest to most recent?

A) Cambrian, Devonian, Permian, Cretaceous
B) Devonian, Cambrian, Permian, Cretaceous
C) Cambrian, Permian, Devonian, Cretaceous
D) Permian, Cambrian, Cretaceous, Devonian

Question 57

Evidence of which structure or characteristic would be most surprising to find among fossils of the Ediacaran fauna?

A) true tissues
B) hard parts
C) bilateral symmetry
D) embryos

Question 58

Assuming the existence of fossilized markers for each of the following chemicals, what is the sequence in which they should be found in this sediment core, working from ancient sediments to recent sediments?
1) chitin coupled with protein
2) chlorophyll
3) bone
4) cellulose

A) 2, 4, 3, 1
B) 2, 4, 1, 3
C) 4, 2, 1, 3
D) 4, 2, 3, 1

Question 59

Which of the following showed their greatest diversity during the Mesozoic era but were a small, less diverse group during the Paleozoic era?

A) gymnosperms
B) fungi
C) flowering plants
D) mammals

Question 60

The largest extinction, measured as a percentage of species that disappeared, occurred at the end of which geological period?

A) Permian
B) Cretaceous
C) Tertiary
D) Devonian
E) Silurian

Question 61

How do mass extinctions differ from background extinctions?

A) Mass extinctions occur over a longer period of time than background extinctions.
B) Mass extinctions, but not background extinctions, are generally caused by competition.
C) Mass extinctions cause a larger proportion of organisms to go extinct than background extinctions.
D) Mass extinctions typically result from Hox gene mutations, and background extinctions typically result from changes in weather patterns.

Question 62

What is still lacking in the hypothesis of an asteroid impact as the cause of the end-Cretaceous mass extinction?

A) evidence for what caused such high species loss after the impact
B) evidence that an asteroid hit Earth at the time of the extinction (65 million years ago)
C) a convincing explanation of why mammals radiated after the event
D) a complete explanation of why some lineages survived while others vanished

Question 63

The major evolutionary episode corresponding most closely in time with the formation of Pangaea was the ________.

A) Cambrian explosion
B) Permian extinctions
C) Pleistocene ice ages
D) Cretaceous extinctions