WHICH OF THE FOLLOWING CONTRIBUTES LEAST TO SPECIATION?

A: SEXUAL REPRODUCTION
B: ASEXUAL REPRODUCTION
C: ISOLATION
D: VARIATION

B

The legless condition that is observed in several groups of extant reptiles is the result of

A) their common ancestor having been legless.

B) a shared adaptation to an arboreal (living in trees) lifestyle.

C) several instances of the legless condition arising independently of each other.

D) individual lizards adapting to a fossorial (living in burrows) lifestyle during their lifetimes.

C

A group of students summarized information on five great extinction events.

The students are sampling a site in search of fossils from the Devonian period. Based on the chart, which of the following would be the most reasonable plan for the students to follow?

(A) Searching horizontal rock layers in any class of rock and trying to find those that contain the greatest number of fossils

(B) Collecting fossils from rock layers deposited prior to the Permian period that contain some early vertebrate bones

(C) Looking in sedimentary layers next to bodies of water in order to find marine fossils of bivalves and trilobites

(D) Using relative dating techniques to determine the geological ages of the fossils found so they can calculate the rate of speciation of early organisms

B

Five new species of bacteria were discovered in Antarctic ice core samples. The nucleotide (base) sequences of rRNA subunits were determined for the new species. The table below shows the number of nucleotide differences between the species.

Which of the following phylogenetic trees is most consistent with the data?

C

The asteroid hypothesis is associated most prominently with which of the following events in the

history of life?

A) origin of life B) origin of humans C) origin of eukaryotes

D) Permian extinctions E) Cretaceous extinctions

E

A common ancestor for both species C and E could be at position number __________.
(a) 1
(b) 2
(c) 3
(d) 4
(e) 5

4

The two extant species that are most closely related to each other are __________.
(a) A and B.
(b) B and C.
(c) C and D.
(d) D and E.
(e) E and A.

C

Which species are extinct?
(a) A and E
(b) A and B
(c) C and D
(d) D and E
(e) cannot be determined from the information provided

a

If this evolutionary tree is an accurate depiction of relatedness, then which of the following should be
correct?
1. The entire tree is based on maximum parsimony.
2. If all species depicted here make up a taxon, this taxon is monophyletic.
3. The last common ancestor of species B and C occurred more recently than the last
common ancestor of species D and E.
4. Species A is the direct ancestor of both species B and species C.
5. The species present at position 3 is ancestral to C, D, and E.
(a) 2 and 5
(b) 1 and 3
(c) 3 and 4
(d) 2, 3, and 4
(e) 1, 2, and 3

e

Which extinct species should be the best candidate to serve as the outgroup for the clade whose common ancestor occurs at position

A

Two species of orchids with different floral anatomy have which type of reproductive isolation

a. behaviorial

b. gamatic

c. habitat

d. mechanical

e. temporal

D

two species of trout that bread in different seasons have which type of reproductive isolation

a. behaviorial

b. gamatic

c. habitat

d. mechanical

e. temporal

E

Two species meadowlarks with different mating songs have which type of reproductive isolation

a. behaviorial

b. gamatic

c. habitat

d. mechanical

e. temporal

A

Two species of garter snakes live in the same region, but one lives in water and the other lives on land have which type of reproductive isolation

a. behaviorial

b. gamatic

c. habitat

d. mechanical

e. temporal

C

mating fruit flies that recognize the appearance odor and sounds of members of their own species but not others have which type of reproductive isolation

a. behaviorial

b. gamatic

c. habitat

d. mechanical

e. temporal

A

The four-chambered hearts of birds and the four-chambered hearts of mammals evolved
independently of each other. If one were unaware of this independence, then one might logically conclude
that __________.
(a) the birds were the first to evolve a 4-chambered heart
(b) birds and mammals are more distantly related than is actually the case
(c) early mammals possessed feathers
(d) the common ancestor of birds and mammals had a four-chambered heart
(e) birds and mammals should be placed in the same family

d

Cladograms (a type of phylogenetic tree) 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

e

Shared derived characters are most likely to be found in taxa that are __________.
(a) paraphyletic
(b) polyphyletic
(c) monophyletic

C

A taxon, all of whose members have the same common ancestor, is __________.
(a) paraphyletic
(b) polyphyletic
(c) monophyletic

C

The term that is most appropriately associated with clade is __________.
(a) paraphyletic
(b) polyphyletic
(c) monophyletic

C

If birds are excluded from the class Reptilia, the term that consequently describes the class Reptilia is
__________.
(a) paraphyletic
(b) polyphyletic
(c) monophyletic

a

The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V—Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

41) How many separate species, both extant and extinct, are depicted in this tree?

6

The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V—Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

42) According to this tree, what percent of the species seem to be extant (in other words, not extinct)?

66%

The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V—Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

43) Which of the five common ancestors, labeled V-Z, has given rise to the greatest number of species, both extant and extinct?Both X and Y can be considered to have given rise to the greatest number of extant and extinct species

both x and y

The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V—Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

44) Which of the five common ancestors, labeled V-Z, has been least successful in terms of the percent of its derived species that are extant?

W

the appearance of a fertile, polyploidy individual within a population of diploid organisms is a possible source of a new species. if this individual is capable of reproducing to form a new population. scientists would consider this to be an example of:
A. allopatric speciation
B. sympatric speciation
C. polygenic speciation
D. genetic drift
E. hardy weinberg equilibrium

B

what is the only factor that can change allele frequencies in populations to produce adaptive evolutionary change?
A. mutation
B. gene flow (immigration)
C. non-random mating
D. genetic drift
E. selection

E

The evolution of several species from a single species, each occupying a different niche

a. adaptive radiation

b. competitive exclusion

c. convergent evolution

d. founder effect

a

the establishment of a genetically unique population through genetic drift

a. adaptive radiation

b. competitive exclusion

c. convergent evolution

d. founder effect

D

the indepedendent development of similarities between unrelated groups resulting from adaptation to similar environments

a. adaptive radiation

b. competitive exclusion

c. convergent evolution

d. founder effect

C

genetic drift is increased by all of the following EXCEPT:
A. small population size
B. bottleneck effects when the population size is greatly reduced, then recovers
C. founder effects when a small number of individuals are isolated and reproduce to form a new sub-population
D. movement of individuals from one isolated population to another
E. genetic isolation of a small groups within a population

D

Interpretation of the data supports which of the following statements?

(A) Rhesus monkeys are more closely related to rabbits than they are to horses.

(B) Horses and cows have identical amino acid sequences in their cytochrome c.

(C) Humans are more closely related to rabbits than they are to rhesus monkeys.

(D) Plants and animals have no similarities at all.

(E) Mammals are more closely related to reptiles than they are to fish.

A

D

in a small group of people in kentucky, there is a high incidence of "blue skin", a condition that results from a variation in structure of the hemoglobin. all of the blue skinned residents can trace their ancestry to one couple, who were among the original settlers of this region. the unusually high frequency of blue skin is an example of
A. mutation
B. genetic drift
C. natural selection
D. sexual selection
E. heterozygote advantage

B

some varieties of the bacteria, neisseria gonorrhoeae, are now resistant to penicillin, these varieties of bacteria most probably developed as a result of...
A. selection
B. hybrid vigor
C. coevolution
D. adaptive radiation
E. convergent evolution

a

although the seal and the penguin both have streamlines, fish-like bodies with a layer of insulating fat, they arent closely related. this similarity results from
A. convergent evolution
B. adaptive radiation
C. homologous evolution
D. coevolution
E. analogous evolution

a

Rates of adaptive radiation typically are at their highest in which of the following situations?
-----------------------------------------------
[A] When Earth is exposed to increased electromagnetic waves caused by Sun flares.

[B] In very large, randomly mating populations.

[C] When new niches become available

[D] When many species are competing for the same limited resource.

[E] When food is abundant.

C

Which of the following best summarizes the theory of punctuated equilibrium?
-----------------------------------------------
[A] After periods of directional selection, the allelic frequencies in a population will reach equilibrium and then undergo disruptive selection.

[B] Most species evolve gradually, with discrete changes appearing in the fossil record at short, regular intervals.

[C] Once one species achieves evolutionary dominance, all of the remaining species must compete among themselves for selective advantages; only then will the dominant species be challenged.

[D] To ensure survival of the fittest, natural selection eliminates those species that disrupt the balance of nature.

[E] Most taxa experience relatively short periods during which they undergo rapid change, followed by relatively long periods during which they undergo relatively little change.

E

Which of the following conclusions is best supported by the cladogram above?
-----------------------------------------------
[A] Species Q and R make up a monophyletic group.

[B] Species P and Q are equally related to species T.

[C] Species P and T do not share a common ancestor.

[D] Species S evolved from species R.

[E] Species S is more closely related to species T than to species R.

E

A large assemblage of land snails is subdivided into two populations (A and B) by a river that effectively isolates the two populations for an indefinitely long period. From an evolutionary standpoint, which of the following is the LEAST likely to occur in the two populations?
-----------------------------------------------
[A] Populations A and B will eventually differ in their ecological requirements.

[B] Population A may ultimately breed at a different time of the year than population B does.

[C] Population A may undergo instantaneous speciation by the doubling of its chromosome numbers (polyploidy).

[D] Under laboratory conditions, cross fertilizations between members of the two populations may be successful even after a long period of geographical separation.

[E] The two populations may become morphologically very dissimilar.

C

What components of the gases found in the early atmosphere were beneficially in providing the building blocks for life

a. N2 gas and ammonia

b. methane and carbon dioxide

c. carbon dioxide and water vapor

d. sulfur dioxide and oxygen

a

Which of the following pairs of plants are most closely related?
1. Broad bean (Vicia faba)
2. Soybean (Glycine max)
3. Kidney Bean (Phaseolus vulgaris)
4. Barley (Hordeum vulgaris)
5. Scarlet runner bean (Phaseolus coccinus)

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

E

Which of the following is the correct sequence of these events in the origin of life?
I. formation of protobionts
II. synthesis of organic monomers
III. synthesis of organic polymers
IV. formation of DNA-based genetic systems
A) I, II, III, IV
B) I, III, II, IV
C) II, III, I, IV
D) IV, III, I, II
E) III, II, I, IV

C

The first genes on Earth were probably
A) DNA produced by reverse transcriptase from abiotically produced RNA.
B) DNA molecules whose information was transcribed to RNA and later translated in polypeptides.
C) auto-catalytic RNA molecules.
D) RNA produced by autocatalytic, proteinaceous enzymes.
E) oligopeptides located within protobionts.

C

If natural selection in a particular environment favored genetic systems that permitted the production of daughter "cells" that were genetically dissimilar from the mother "cells," then one should expect selection for
I. polynucleotide polymerase with low mismatch error rates.
II. polynucleotide polymerases without proofreading capability.
III. batteries of efficient polynucleotide repair enzymes.
IV. polynucleotide polymerases with proofreading capability.
V. polynucleotide polymerases with high mismatch error rates.
A) I only
B) I and IV
C) I, III, and IV
D) II and V
E) II, III and V

D

What is true of the fossil record of mammalian origins?
A) It is a good example of punctuated equilibrium.
B) It shows that mammals and birds evolved from the same kind of dinosaur.
C) It includes transitional forms with progressively specialized teeth.
D) It indicates that mammals and dinosaurs did not overlap in geologic time.
E) It includes a series that shows the gradual change of scales into fur.

C

An early consequence of the release of oxygen gas by plant and bacterial photosynthesis was to
A) make life on land difficult for aerobic organisms.
B) change the atmosphere from oxidizing to reducing.
C) make it easier to maintain reduced molecules.
D) cause iron in ocean water and terrestrial rocks to rust (oxidize).
E) prevent the formation of an ozone layer.

D

Recent evidence indicates that the first major diversification of multicellular eukaryotes may have coincided in time with the
A) origin of prokaryotes.
B) switch to an oxidizing atmosphere.
C) melting that ended the "snowball Earth" period.
D) origin of multicellular organisms.
E) massive eruptions of deep-sea vents.

C

Which event is nearest in time to the end of the period known as snowball Earth?
A) oxygenation of Earth's seas and atmosphere
B) evolution of mitochondria
C) Cambrian explosion
D) evolution of true multicellularity
E) Permian extinction

C

There are at least a dozen known species in the extinct genus Lystrosaurus. If each species was suited to a quite different environment, then this relatively large number of species is likely due to
A) sexual selection.
B) adaptive radiation.
C) heterochrony.
D) polyploidy.
E) species selection.

B

If these fly species lost the ability to fly independently of each other as a result of separate mutation events in each lineage, then the flightless condition in these species could be an example of
A) adaptive radiation.
B) species selection.
C) sexual selection.
D) allometric growth.
E) habitat differentiation.

B

Which example below will most likely guarantee that two closely related species will persist only as distinct
biological species?
A) colonization of new habitats
B) convergent evolution
C) hybridization
D) geographic isolation from one another
E) reproductive isolation from one another

e

Which of these should decline in hybrid zones where reinforcement is occurring?
A) gene flow between distinct gene pools
B) speciation
C) the genetic distinctness of two gene pools
D) mutation rate
E) hybrid sterility

a

According to the concept of punctuated equilibrium, the ʺsuddenʺ appearance of a new species in the fossil
record means that
A) the species is now extinct.
B) speciation occurred instantaneously.
C) speciation occurred in one generation.
D) speciation occurred rapidly in geologic time.
E) the species will consequently have a relatively short existence, compared with other species.

d

According to the concept of punctuated equilibrium,
A) natural selection is unimportant as a mechanism of evolution.
B) given enough time, most existing species will branch gradually into new species.
C) a new species accumulates most of its unique features as it comes into existence.
D) evolution of new species features long periods during which changes are occurring, interspersed with
short periods of equilibrium, or stasis.
E) transitional fossils, intermediate between newer species and their parent species, should be abundant.

c