Deck 16: Evolution on a Large Scale

Question 1

Which of the following correctly reflects the division of the history of life on Earth, from most inclusive to least inclusive?

A) era - period - epoch
B) epoch - period - era
C) era - epoch - period
D) epoch - era - period
E) period - epoch - era An era is composed of two or more periods, and a period is composed of two or more epochs.

Answer 1

A

Question 2

A major difference between allopatric and sympatric speciation is whether

A) the resulting species are reproductively isolated or not.
B) gene flow continues to occur or not.
C) two or three species result.
D) geographic isolation is required or not.
E) the new species are separated by a prezygotic or postzygotic isolating mechanism. The prefix allo- means "different," whereas the prefix sym- means "same." The root word of both terms, patria, loosely means "homeland." Thus, the two types of speciation are differentiated by whether or not geographical isolation is required-allopatric meaning "different homeland," and sympatric meaning "same homeland."

Answer 2

D

Question 3

Which of the following is not thought to have contributed to the many mass extinction events that have occurred throughout Earth's history?

A) plate tectonics
B) habitat loss
C) meteorite impacts
D) continental drift
E) punctuated equilibrium The movement of continents continental drift) as a result of plate tectonic activity is thought to have greatly reduced some types of habitats and contributed to mass extinction events at various times. Likewise, cataclysmic events such as a meteorite impact may have caused the mass extinction of the dinosaurs. Only the punctuated equilibrium model, which merely suggests that species tend to remain mostly the same for long periods of time before rapidly evolving, is not a cause of mass extinction events.

Answer 3

E

Question 4

Most dinosaurs became extinct at the end of which of the following periods of the Mesozoic?

A) Jurassic
B) Cretaceous
C) Devonian
D) Triassic
E) Permian Dinosaurs first appeared during the Triassic period and flourished during the Jurassic period; then most became extinct at the end of the Cretaceous period, marking the end of the Mesozoic era.

Question 5

The finches of the Galápagos islands evolved as a result of what types) of speciation?

A) allopatric speciation
B) adaptive radiation
C) sympatric speciation
D) both allopatric speciation and adaptive radiation
E) both sympatric speciation and adaptive radiation The Galápagos finches are usually presented as an example of adaptive radiation, a mechanism by which multiple species arise from a common ancestor. However, the speciation of the finches also involves allopatric speciation, in which the reproductive isolation of populations of finches resulted in their speciation. Thus, the speciation of finches in the Galápagos reflects both adaptive radiation and allopatric speciation.

Question 6

Which of the following is not a prezygotic isolating mechanism for two species found in the same geographical location?

A) The two species occupy different habitats.
B) The two species are active during different parts of the day.
C) The two species mate during different times of the year.
D) The two species have incompatible genitalia.
E) The two species can mate, but the offspring are sterile. The instance where the two species are capable of mating but produce sterile offspring is an example of a postzygotic isolating mechanism because the event that prevents the two species from interbreeding occurs when the offspring are unable to reproduce.

Question 7

The punctuated equilibrium model of evolution suggests that new species appear

A) gradually; as groups become isolated, they slowly evolve through their own individual pathways.
B) only after older species disappear from the fossil record.
C) suddenly after long periods of time with little to no change.
D) gradually after long periods of time with little to no change; as groups become isolated, they slowly evolve through their own individual pathways.
E) gradually over very short periods of time so that intermediate species are often observed in the fossil record. In the punctuated model of evolution, a species remains fairly stable for long periods of time, which are suddenly punctuated by rapid spurts of evolution where new species appear. This suggests that intermediate, or transitional, species are rare, and are thus seldom found in the fossil record.

Question 8

Two species are said to be closely related if they

A) possess a common ancestor.
B) can interbreed but not produce fertile offspring.
C) are reproductively isolated from each other.
D) have a shared gene pool.
E) can interbreed and produce fertile offspring. Two species are closely related if they possess a common ancestor. The ability to interbreed, whether or not fertile offspring are obtained, does not necessarily indicate that the two species are closely related.

Question 9

A reproductive barrier that prevents interbreeding because the two species mate during different times of the year is called an)

A) hybrid sterility isolation.
B) postzygotic isolating mechanism.
C) F₂ fitness isolation.
D) temporal isolation.
E) behavioral isolation. Temporal isolation refers to a type of prezygotic isolating mechanism that prevents interbreeding when two species reproduce at different times of the year or during different times of day.

Question 10

The fossils of a new species of reptile are found in deposits dating to the Permian period. Later, scientists discover that fossils of the species changed somewhat over time and can be found in deposits dating from the Permian period all the way up to the Cretaceous period. The fossils vary from one continent to another, but many seemingly intermediate forms are found, and the fossils are spread over most continents. The scientists' observations most strongly support which evolutionary models)?

A) allopatric speciation
B) punctuated evolution
C) adaptive radiation
D) both allopatric speciation and adaptive radiation
E) gradualistic evolution The observations that the fossils are found on most continents and that they have changed over long periods of time suggest the gradualistic model of evolution. The spread of the fossils over multiple continents also suggests that speciation occurred in the Permian period, when the continents were joined together, and that a slow, gradual evolution occurred while the continents separated, throughout the Paleozoic and Mesozoic eras. The observation that many intermediate forms are found suggests that all of the fossils belong to the same species because significant amounts of interbreeding between populations probably occurred.

Question 11

A zygote fails to undergo mitosis because of a mismatch in the number of chromosomes. This is an example of

A) hybrid sterility.
B) zygote mortality.
C) prezygotic isolation.
D) temporal isolation.
E) allopatric speciation. In this case, mating occurs but fails after the zygote dies due to the inability to complete mitosis. Thus, this is an example of zygote mortality.

Question 12

The pollen, or sperm, from a red maple tree is unable to fertilize the eggs from a sugar maple tree. This is an example of what type of isolating mechanism?

A) mechanical isolation
B) habitat isolation
C) temporal isolation
D) hybrid sterility
E) gamete isolation This is an example of gamete isolation because the gametes from the two species are unable to fuse.

Question 13

Significant mass extinctions occurred during which of the following peroids?

A) Pleistocene, Ordovician, and Triassic
B) Ordovician, Triassic, and Jurassic
C) Triassic, Permian, and Cretaceous
D) Triassic, Permian, Cretaceous, Pleistocene, Ordovician, and Devonian
E) Ordovician, Triassic, Jurassic, Silurian, Eocene, and Oligocene The Triassic, Permian, Cretaceous, Pleistocene, Ordovician, and Devonian periods all ended with mass extinction events. However, most scientists also agree that mass extinctions continue throughout the modern Holocene epoch due to the activities of human civilization.

Question 14

Which of the following is an example of sympatric speciation?

A) two populations of salamanders that live on isolated islands and eventually become separate species, unable to interbreed
B) different breeds of dogs that live in different areas of the world but are able to produce fertile offspring
C) a horse and a donkey that may interbreed to produce a mule that is sterile and unable to reproduce
D) two related plant species living in the same area that hybridize, then undergo chromosome doubling, which results in the creation of a third species of plant that is unable to reproduce with either of the two original species
E) three species that evolve from a common ancestral species due to reproductive isolation and adaptation to different habitats Sympatric speciation refers to populations that develop into two or more new species without prior geographic isolation. Hybridization followed by polyploidy in plants is an excellent example of this type of speciation mechanism.

Question 15

Which of the following is not part of the punctuated equilibrium model?

A) There is a period of no change interrupted by speciation.
B) Transitional fossils are less likely to be found.
C) It is difficult to determine when speciation occurred.
D) It often involves an isolated subpopulation.
E) Speciation often occurs rapidly. In the punctuated equilibrium model, speciation occurs rapidly after long periods of little to no change, making transitional fossils rare. Rapid speciation events can occur from isolated populations, but once fossils of the new species are discovered, it is relatively straightforward to determine the point in time at which the speciation event occurred.

Question 16

Which of the three domains contains) prokaryotic organisms?

A) Bacteria
B) Archaea
C) Eukarya
D) Bacteria and Archaea
E) Bacteria, Archaea, and Eukarya The domains Bacteria and Archaea contain prokaryotic organisms, while the domain Eukarya contains eukaryotic organisms.

Question 17

In the three-domain system of classification

A) eukaryotes are more similar to the prokaryotes now classified in domain Bacteria than to those now classified in domain Archaea.
B) animals and plants are less similar to each other than to the prokaryotes now classified in domain Archaea.
C) prokaryotes are classified into two domains, with the organisms in domain Archaea more similar to eukaryotes than to the prokaryotes in domain Bacteria.
D) cladistics alone are used to formulate the new phylogenetic tree of life.
E) by the principle of parsimony, it requires fewer assumptions to divide the prokaryotes into two domains than it does to put them in a single domain. Analysis of rRNA genes indicate that some prokaryotes, now classified as the domain Archaea, are more similar to eukaryotes than to the other prokaryotes that are now classified in the domain Bacteria.

Question 18

Sympatric speciation occurs more commonly in which types of organisms?

A) plants
B) humans
C) birds
D) fish
E) insects Plants are more prone to sympatric speciation because hybrid sterility is not as much of a problem for plants as it is for other organisms. Because plants are tolerant of polyploidy, the doubling of chromosomes within a hybrid may allow it to undergo meiosis successfully and reproduce, producing a new species.

Question 19

Elaborate courtship behavior in animals, such as with the blue-footed boobies of the Galápagos Islands, is an example of which of the following reproductive barriers?

A) behavioral isolation
B) mechanical isolation
C) temporal isolation
D) postzygotic isolation
E) hybrid sterility Because female blue-footed boobies reject mates that do not perform the correct courtship behavior, this is an example of a behavioral isolation mechanism.

Question 20

Which of the following correctly shows a possible order of events resulting in allopatric speciation?

A) postzygotic reproductive isolation - geographic isolation - natural selection
B) geographic isolation - prezygotic reproductive isolation - genetic drift
C) geographic isolation - natural selection - prezygotic reproductive isolation
D) natural selection - postzygotic reproductive isolation - geographic isolation
E) natural selection - prezygotic reproductive isolation - postzygotic reproductive isolation In allopatric speciation, two populations of the same species are separated geographically, preventing them from interbreeding with each other. Over time, the species gradually change, and prezygotic and postzygotic isolating mechanisms develop, preventing the two populations from reproducing if the populations ever come into contact again.

Question 21

Which of the following statements is true about the phylogenetic tree shown here?

A) A combination of molecular data, fossil records, and anatomical homologies shows the human is more closely related to the chimpanzee than to the green monkey.
B) The green monkey and rhesus monkey cannot reproduce with each other because of a postzygotic isolating mechanism.
C) The chimpanzee and human must have evolved as a result of allopatric speciation.
D) There is no single common ancestor to all of the organisms displayed on this phylogenetic tree.
E) The gibbon and human are no more closely related than the green monkey and human are. The correct statement here is that the human is more closely related to the chimpanzee than to the green monkey. The phylogenetic tree provides no information regarding the method of speciation or whether it is maintained by a prezygotic or postzygotic isolating mechanism. All of the organisms on the tree are related to a single common ancestor about 40 MYA the "root" of the tree). The gibbon and human share a more recent common ancestor 25 MYA) than do the human and green monkey 30 MYA), so that statement is not true.

Question 22

Homologous structures

A) have identical functions.
B) have fully divergent functions.
C) are also called analogous structures.
D) are shared by organisms of the same genus.
E) are often shared by organisms in the same line of descent. Homologous structures are those that are shared by organisms found in the same line of descent. Over the course of speciation, the structures may or may not have attained different functions, but they still have evolved from the same original structure.

Question 23

Which of the following lists the levels of taxonomic classification in order from the most inclusive to the least inclusive?

A) genus - family - order - class - phylum
B) phylum - order - class - family - species
C) genus - order - family - class - phylum
D) family - order - class - phylum - kingdom
E) domain - kingdom - phylum - class - order Domains are the most inclusive classification, while a species is the least inclusive. Thus, domain - kingdom - phylum - class - order is in the correct order from most to least inclusive.

Question 24

Pinus strobus is the scientific name for the white pine. Pinus is the

A) specific epithet.
B) genus.
C) binomial name.
D) family name.
E) order name. The binomial nomenclature used by systematists includes the organism's genus and specific epithet.

Question 25

Members of two different species are never capable of mating.

Question 26

Which of the following statements is true about the shown cladogram and the characters used to derive it?

A) Three-chambered heart is the most inclusive character on the cladogram.
B) The snake and lizard share a common ancestor that does not have the characters internal fertilization or amniotic membrane in egg.
C) The character notochord in embryo is not shared by the common ancestor to all of the organisms on the cladogram.
D) The two organisms furthest from each other on the cladogram share only two common characters.
E) The character long cylindrical body is useful in placing the snake and eel into the cladogram. It can be seen that an earlier common ancestor to the snake and lizard, also shared with the newt, did not possess the characters internal fertilization or amniotic membrane in egg.

Question 27

Evolutionary relationships between organisms are determined by

A) molecular evidence and anatomical homologies.
B) molecular evidence, anatomical homologies, and fossil records.
C) molecular evidence, anatomical analogies, and fossil records.
D) molecular evidence and fossil records.
E) molecular evidence, anatomical homologies, anatomical analogies, and fossil records. Anatomical analogies are not useful in determining evolutionary relationships because they are the result of convergent evolution. In convergent evolution, distantly related organisms may develop similar adaptations to the same environment, but this does not imply an evolutionary relationship between the two organisms.

Question 28

Allopatric speciation is compatible with both the gradualistic and punctuated equilibrium models of evolution.

Question 29

In the figure shown here, the letter W represents which of the following?

A) the common ancestor for Y and Z
B) the common ancestor for U
C) the ancestor for Z
D) the common ancestor for X and Y
E) the common ancestor for X, Y, and Z Descendents of a common ancestor are shown on branches of the cladogram originating from the common ancestor.

Question 30

Similarity due to convergent evolution is called

A) analogy.
B) homology.
C) taxonomy.
D) phylogeny.
E) cladistics. Similarity due to convergent evolution is called analogy. Analogous structures have the same function in different organisms and groups of organisms, and they often arise as a result of adaptation to the same type of environment.

Question 31

The term parsimony implies that

A) the three-domain system is superior to the five-kingdom system of classification.
B) molecular data are more accurate in implying evolutionary relationships than homology.
C) the fewer assumptions that are made, the more probable the conclusion.
D) smaller clades are more accurate than larger clades.
E) shared derived traits shared by fewer organisms are more correct than those shared by more organisms. The principle of parsimony only implies that a conclusion is more likely correct when fewer assumptions are made. Larger, more complex clades may be constructed when fewer assumptions are made, and by the principle of parsimony, these clades are more likely to be correct than those constructed using more assumptions.

Question 32

A clade includes which of the following?

A) an outgroup and an ingroup
B) a common ancestor and all its descendant species
C) one taxon with shared derived characters
D) an ancestor and all its descendant species, and taxa with shared derived characters
E) an ingroup only A clade consists of a common ancestor with all descendant species.

Question 33

Use of chemical signals in mate recognition is a type of postzygotic isolating mechanism.

Question 34

Which of the following would be considered analogous structures?

A) the forelimb of a bat and the forelimb of a horse
B) the wings of a fly and the wings of a sparrow
C) the pelvis of a human and the pelvis of a whale
D) the flipper of a dolphin and the arm of a human
E) the wings of a bird and the forelimbs of a reptile Analogous structures are those that evolve separately to achieve the same function and often appear in unrelated organisms. The wings of insects and the wings of birds both serve the same purpose.

Question 35

In the figure shown here, which of the following organisms would have the same shared derived trait?

A) W, Y, and Z
B) W, X, Y, and Z
C) V, W, X, and Y
D) X, Y, and Z
E) U, V, W, and Z A shared derived trait can be found in all organisms descending from a common ancestor that are found on the same branch of the clade.

Question 36

A shared ancestral characteristic used in cladistics is found

A) only in the two most recent ancestors.
B) only among the members of the ingroup.
C) in both the outgroup and the ingroup.
D) in two of the outgroups.
E) only in the most distant ancestor. A shared ancestral trait is one that is presumed to have appeared in the common ancestor to the members of both the ingroup and outgroup. It is not a shared derived trait, so it is not used to construct the cladogram.

Question 37

In the figure shown here, ________ and ________ have a common shared derived trait that is not possessed by ________.

A) X; Y; Z
B) Y; Z; X
C) Y; Z; W
D) X; Z; W
E) W; Y; Z A shared derived trait can be found in all organisms descending from a common ancestor that are found on the same branch of the clade. Although X, Y, and Z will share at least one shared derived trait, Y and Z will possess a shared derived trait that is not shared by X.

Question 38

Which of the following statements is true about the phylogenetic tree shown here?

A) The gibbon is more closely related to the rhesus monkey than to the chimpanzee.
B) The galago is more closely related to the green monkey than to the capuchin.
C) The green monkey and rhesus monkey share a common ancestor with the gibbon and chimpanzee.
D) The gibbon does not share a common ancestor with the chimpanzee or human.
E) The green monkey and rhesus monkey share a more recent common ancestor than do the chimpanzee and human. The only correct statement here is that the green monkey and rhesus monkey share a common ancestor with the gibbon and chimpanzee, about 30 MYA. The galago is no further removed from the capuchin than it is from the green monkey ancestor about 40 MYA). The gibbon shares a more recent common ancestor with the chimpanzee about 25 MYA) than it does with the rhesus monkey about 30 MYA). The green monkey and rhesus monkey share a common ancestor about 20 MYA, while the chimpanzee and human share a common ancestor only about 5 MYA.

Question 39

Shared derived traits

A) are shared only by common ancestors.
B) are shared by all organisms on the cladogram.
C) are found within members of the outgroup.
D) are homologies found only in certain members of the ingroup.
E) are homologies found between the ingroup and the outgroup. Shared derived traits are homologies that are shared only by certain species within the ingroup. They are found only within members of the ingroup that share a common lineage. Species that arose earlier may not possess the shared derived trait but are nonetheless part of the same clade. Shared derived traits are used to determine which members of the clade belong on the same branch of the cladogram.

Question 40

A phylogenetic tree

A) indicates common ancestors.
B) indicates the organism's taxon.
C) uses only derived characters.
D) indicates common ancestors for each family.
E) includes the organism's order and class. A phylogenetic tree indicates both an organism's ancestors and its lines of descent. It does not directly indicate the taxon of an organism.

Question 41

Geographic isolation is not a factor in sympatric speciation.

Question 42

The gradualistic model of speciation is supported by many transitional forms.

Question 43

Convergent evolution gives rise to analogous structures in unrelated taxa.

Question 44

Two organisms present in the same genus are usually more closely related to each other than to organisms in other genera.

Question 45

Which geological timescale contains the greatest number of years?

A) eras
B) periods
C) epochs
D) centuries
E) decades The geological timescale divides the history of life on Earth into eras, then periods, and then epochs.

Question 46

Which event was not involved in the Permian mass extinction?

A) dramatic environmental change
B) shifting wind patterns
C) shifting ocean currents
D) a decrease in the amount of shallow marine habitat
E) a large meteor impact We know that 250 million years ago, at the time of the Permian mass extinction, all of Earth's continents came together to form one supercontinent called Pangaea Fig. 16.14a). The result was dramatic environmental change through the shifting of wind patterns and ocean currents and, most importantly, a decline in the amount of available shallow marine habitat. It was at the end of the Mesozoic era that a meteor crashed into Earth. This type of event has been proposed as a primary cause of the Cretaceous extinction.

Question 47

Cladograms show the sequence of evolution of the characters in a clade.

Question 48

The presence of which feature is the first step to being classified in domain Eukarya?

A) membrane-bound nucleus
B) ribosomes
C) cell wall
D) chloroplast
E) mitochondria Eukaryotic organisms are classified as such due to the presence of a membrane-bound nucleus. Most of the other features listed here can be found in members of domain Bacteria and domain Archaea as well as domain Eukarya. However, mitochondria and chloroplasts are not traits shared by the prokaryotic domains.

Question 49

Shared derived traits are found in all members of the ingroup of a clade.

Question 50

Three species that arose as a result of adaptive radiation are organized on a cladogram. On this cladogram, two of the species would likely share several characters not present in the third.

Question 51

The ribosomal RNA rRNA) genes of different organisms are often compared as a means to classify them because rRNA genes evolve much more slowly than other genes.