Evolution Final
A new mutation arises in a population of spiders, which are diploid, with a population size of 116. If that mutation is neutral, what is the probability that it will eventually go to fixation in the population? a) 0.0043 b) 0.045 c) 0 d) 0.5 e) We cannot predict from these data.
a
Genomic data support the hypothesis that Neanderthals were: a) a distinct lineage of hominin that interbred with some lineages of humans. b) direct ancestors of modern humans. c) a distinct lineage of hominin that went extinct without contributing any DNA to modern humans. d) not related to other hominin. e) a fictional lineage popularized by cartoons.
a
Imagine an island archipelago where all of the islands are founded by individuals heterozygous at a particular locus. If there is no migration or mutation, and the alleles at the locus are neutral, what do you expect the island populations to look like after many generations? a) Some island populations will have fixed one allele, and other populations will have fixed the other allele. b) The populations of every island will have fixed the same allele. c) The island populations will have high levels of genetic diversity at this locus. d) We cannot predict any outcome because genetic drift is a random process.
a
Male magnetic pinching beetles have two mating tactics: large males guard females whereas small males sneak copulations. Guarders have much higher fitness than sneakers. Of the reasons below, which is the most likely reason why sneakers persist evolutionarily? a) Male body size likely has a strong environmental component, meaning there will always be small males. b) Male mating tactic fitness is negative frequency dependent, producing oscillations in tactic frequency but maintaining both. c) Sexual selection by females use a sexy son tactic to selectively mate with small males. d) Small male size is an honest signal of male quality. e) Genetic correlations between female preference and male quality aid in the persistance of small male genotypes.
a
Muller's Ratchet a) does not function in sexual populations of any size because they can purge deleterious mutations. b) does not function in large asexual populations because they can purge deleterious mutations. c) does not function in small asexual populations because they can purge deleterious mutations. d) is facilitated by drift in large, sexual populations. e) opposes Haldane's Rule.
a
Random mutations are most often neutral in which of the following types of genomic sequence? a) Pseudogenes b) Protein coding genes c) RNA genes d) 5' untranslated regions e) Nonsynonymous sites f) Neutral mutations will occur with equal frequency in all of these sequences
a
The idea that there are mutually exclusive trade-offs among investment among growth, maintainance and reproduction is central to : a) life history theory. b) quantitative genetics theory. c) sexual selection theory. d) levels of selection theory. e) Dobzhansky Muller incompatibilities.
a
The resemblance between parents and offspring is not perfect because : a) parents and offspring may experience different environments during development and growth. b) investigators cannot measure traits accurately between parental and offspring generations. c) negative frequency dependent selection favors different phenotypes between generations. d) additive genetic variation is subject to natural selection. e) linkage disequilibrium makes maternal and paternal alleles non-independent.
a
The theory of evolution is best described as: a) What are held to be the general causes of descent with modification. b) A process that cannot be tested. c) Beliefs about common descent. d) The theory of transitions from lower to higher organisms. e) The patterns of common ancestry and descent with modification.
a
Which of the following must occur, or must have occurred at some point, in order for evolution by natural selection to take place? a) Mutation b) Homology c) Genetic drift d) Sexual reproduction
a
be identified as an adaptation, all of the following MUST be demonstrated EXCEPT a) Stastically significant phylogenetically independent contrasts. b) That the trait arose for its current purpose through natural selection. c) That individuals possessing the possible adaptation have higher fitness than those that do not. d) That the current fitness enhancing function of the trait was absent in ancestral lineages. e) All of the above need to be demonstrated to establish a trait as an adaptation.
a
A growing body of evidence implicates important roles for telomeres and telomerase action in the evolution of senescence. Increased telomere length or telomerase action is associated with increases in longevity. One negative side effect of decreased senescence through these mechanisms is that: a) longer lived cells result in expression of other reproductive costs. b) longer lived cells are more likely to accumulate mutations, leading to disease such as cancer. c) longer life alters the optimal number of offspring an individual should produce, negatively affecting the evolutionary trajectory of ill adapted populations. d) higher telomerase action increases stress hormone levels, thereby increasing longevity at the expense of health. e) they make people look like naked mole rats.
b
A rancher genotypes all of her 150 head of cattle at a neutral locus, A. In her herd, 25 are AA, 75 are Aa, and 50 are aa. Assuming there is random mating, no selection, no mutation, and no new cattle are introduced to the population, what is the probability that the A allele will eventually be fixed in the population? (A allele/total alleles= ?) a) 0 b) 0.4167 c) 0.6588 d) 1.0 e) We cannot predict from these data.
b
Allopatric speciation, where lineages diverge after being separated by a vicariant event, a) cannot occur under the phylogenetic species concept. b) can result from the accumulation of different mutations on either side of the barrier. c) is dependent on the barrier remaining in place once speciation is complete. d) sets the stage for peripatric or sympatric speciation, depending on the evolution of Dobzhansky-Muller incompatibilities. e) can only occur in terrestrial species.
b
Asexual reproduction a) is good because it increases linkage disequilibrium. b) can be favored in stable environments where there is little advantage to genetic diversity among offspring. c) is good because it decreases linkage disequilibrium br> d) produces drift under Muller's Ratchet. e) is favored in fluctuating environments due to negative frequency dependent selection imposed by red queen dynamics.
b
Consider a locus with two alleles, A and a. Under which of the following scenarios will both alleles be maintained in the population? a) The fitness of the AA and Aa individuals is higher than the fitness of the aa individuals. b) The fitness of the heterozygote is higher than the fitness of the either homozygote. c) The fitness of the heterozygote is lower than the fitness of either homozygote. d) The fitness of aa individuals is higher than the fitness of Aa and AA individuals. e) There are no fitness differences among the genotypes and the population size is small.
b
Epistatic variance a) accelerates adaptive evolution. b) can be affected by genetic background. c) opposes antagonistic pleiotropy. d) causes antagonistic pleiotropy. e) contributes little to phenotypic variation. f) none of the above.
b
One proposed resolution to the C-value paradox of genome size is that genome size is a consequence of the interaction of genetic drift and natural selection. Which of the following statements best describes this hypothesis? a) Changes in genome size are neutral and therefore their fixation in a population is determined by genetic drift. Since genetic drift is stronger in smaller populations, organisms with small population sizes will have larger genome sizes. b) Mutations that increase genome size are slightly deleterious and can only be eliminated from species with large population sizes. Thus, genome size is largely determined by population size. c) Natural selection cannot act on genome size because genome size is not a trait with heritable genetic variation. Thus, it is primarily determined by genetic drift. d) Increases in genome size are beneficial because they can result in new genes. Thus, species that have high beneficial mutation rates will have the largest genome sizes. e) None of the above are reasonable hypotheses to explain the C-value paradox.
b
Strong artificial selection a) truncates typical development to increase evolutionary rates. b) opposes natural selection. c) works against selective sweeps and in favor of background selection. d) can produce an evolutionary increase in recombination rate. e) enhances the effect of drift on linkage disequilibrium.
b
The combining of different viral types in a host that results in a new virus is called a) antigenic drift. b) antigenic shift. c) antigenic displacement. d) endogenous retroviruses. e) pandemic.
b
What are the two major types of empirical research in evolutionary biology? a) Natural selection and genetic drift b) Observation and manipulation c) Empirical and theoretical d) Experiments and research e) Beneficial and deleterious
b
Which of the following statements about linkage disequilibrium are true? a) Linkage disequilibrium always increases fitness. b) Linkage disequilibrium can make the evolutionary fate of alleles at linked loci non-independent. c) Frequency dependent selection produces feedback oscillations in the sign of D, the disequilibrium coefficient. d) Linkage disequilibrium occurs when there is epistasis for heterozygosity. e) Recombination reduces epistasis for fitness.
b
Which of the following statements is NOT true? a) Heritability can be affected by the environment. b) Heritability is higher for kin-selected traits. c) Heritability can be affected by genetic background. d) Heritability reflects the resemblance between offspring and parents. e) Heritability can change in response to selection.
b
To be most effective, a species concept should: a) Maximize the number of species identified. b) Reflect the biological reality of the evolutionary independence among lineages. c) Be applicable across diverse taxa regardless of their reproductive mode or other biological quirks. d) Minimize the number of species identified. e) Generate biogeographic patterns in speciation. f) favor splitting over lumping.
b and c
Consider a population of lizards living on the coast of Africa. A storm creates piles of debris that the lizards use to raft to a far away uninhabited island. Which evolutionary process is happening? a) Frequency dependent selection b) Mutation c) Founder effect d) Directional selection e) None of the above
c
Flower color in morning glories (Ipomoea purpurea) is determined by two alleles at a locus. The allele for purple color is dominant to the allele for white color. In a population that is in Hardy-Weinberg equilibrium, we count 32 out of 200 individuals that have white flowers. What percentage of the population is expected to be heterozygous for flower color? a) 16% b) 25% c) 48% d) 36% e) 50%
c
From the list below, pick the most important advantage of sexual reproduction over asexual reproduction. a) Sexual reproduction produces genome dilution that enhances male fitness. b) Sexual reproduction repairs linkage disequilibrium. c) Sexual reproduction produces high variance in fitness. d) Sexual reproduction enhances reproductive rates in offspring. e) Sexual reproduction allows for mate choice.
c
Heritability : a) estimates are not accurate when there is epistasis for fitness. b) cannot be estimated when there is no response to selection. c) can change in response to selection. d) estimates are valid for the same trait across environments and time. e) None of the above.
c
If chimpanzee and human genome differ by only about 1% at the level of DNA base pairs, how might we explain the dramatic differences in appearance, behavior, etc. between humans and chimps? a) There is a correlation between increased rates of divergence with known functions of alleles in humans and chimps. b) Natural selection has been acting on clusters of genes associated with both survival and reproduction in humans and chimps. c) Important differences exist in the expression of genes in humans and chimps. d) Humans and chimps have been diverging from each other for much longer than they have with other primates. e) Humans and chimps share very little genetic material.
c
Muller's Ratchet a)results from mutation accumulation in small, sexual populations. b)results from mutation accumulation in asexual or sexual populations regardless of size. c) results from mutation accumulation in small, asexual populations. d) results from mutation accumulation in large, sexual populations. e) opposes Haldane's Rule.
c
Sex a) is good because it reduces linkage disequilibrium. b) is costly but beneficial because male-female couples are more effective at raising fit offspring than a single parent. c) imposes costs through reduction of female genetic representation in the next generation relative to asexual reproduction. d) speeds up Muller's Ratchet. e) opposes speciation.
c
What is one of the major goals of evolutionary medicine? a) To evolve the human population so as to eliminate deleterious mutations and fix beneficial alleles. b) To circumvent the barriers to good health imposed by socioeconomic and political circumstances. c) To use evolutionary theory to develop an understanding of why we get sick in order to better treat and prevent illness. d) To replace traditional medicine with medical technology developed by experimental evolution. e) To determine the proximate explanations for why we get sick and thereby prevent the spread or development of disease.
c
A new neutral mutation arises in a population of 50 diploid individuals. What is the probability that that mutation will go to fixation? a) 0.005 b) 0.025 c) 1 d) 0.01 e) 0.25
d
According to Charles Darwin, which of the following is a requirement for the process of evolution by natural selection? a) Random chance b) Uniformitarianism c) Small population size d) Variation among individuals e) Effectively neutral alleles f) Common descent
d
Before baseball cards came with a stick of gum, they came with a pack of cigarettes. And besides just baseball, they had a variety of themes. The cigarette card pictured below was from a series of "Common Fallacies." Why is it false to say, "According to Darwin we are descended from monkeys?" a) Darwin never made any statements about human evolution, thus he could not have said that we are descended from monkeys. b) Humans are not related to monkeys, thus we cannot have descended from them. c) Monkeys are monophyletic with apes, thus we are actually descended from apes. d) Humans and monkeys are descended from a common ancestor, but that ancestor is not the same as a modern monkey. e) Human ancestors did not interbreed with monkeys, so monkeys cannot be related to humans.
d
Consider a locus with three alleles in a population, A1, A2, and A3. If the frequency of A1 is p, the frequency of A2 is q, and the frequency of A3 is r, and the population is in HardyWeinberg equilibrium, what is the frequency of individuals that are heterozygous for the A1 and A3 alleles? a) 1.0 b) 2pqr c) p+q+r d) 2pr e) 2.0
d
From the list below, pick the most important advantage of sexual reproduction over asexual reproduction. a) Sexual reproduction produces genome dilution that enhances male fitness. b) Sexual reproduction repairs linkage disequilibrium. c) Sexual reproduction generates higher mean fitness in offspring. d) Sexual reproduction provides a mechanism to purge deleterious mutations from a population. e) None of the above are true advantages of sexual reproduction.
d
Male yarnfish have two mating tactics: large males guard females whereas small males sneak copulations. Guarders have much higher fitness than sneakers. Of the reasons below, which is the most likely reason why sneakers persist evolutionarily? a) Male mating tactic fitness is negative frequency dependent, producing oscillations in tactic frequency but maintaining both. b) Sexual selection by females use a sexy son tactic to selectively mate with small males. c) Small male size is an honest signal of male quality. d) Male body size likely has a strong environmental component, meaning there will always be small males. e) Genetic correlations between female preference and male quality aid in the persistance of small male genotypes.
d
Muller's Ratchet a) breaks negative frequency dependent feedback loops. b) increases the efficacy of selection in in small, asexual populations. c) increases the cost of males two-fold. d) can cause the extinction of small, asexual populations. e) all of the above
d
Recombination a) has no impact on the response to selection. b) has the disadvantage of breaking up allele combinations across loci across generations, producing genetically variable offspring. c) inhibits the response to selection in stable environments. d) rates can increase in as an indirect response to selection to change the average value of a trait. e) is facilitated by high variance for disequilibrium.
d
Reproductive character displacement a) produces allopatric species. b) is when the costs of sex are reduced enough to permit asexual reproduction. c) is when an individual achieves fitness through the reproduction of relatives. d) is caused by selection against hybridization between species in areas of sympatry. e) results from mate choice on traits unrelated to fitness (e.g., sexy sons).
d
Sexual selection often favors different mating tactics for each sex. In general : a) sexual selection should favor the evolution of cooperative breeding. b) the sex that has more opportunities to mate is subject to strong sexual selection. c) alterative mating tactics persist evolutionarily because they offer superior fitness for the most competitive phentoypes. d) the sex that invests more time and energy in reproduction should be choosey. e) alterative mating tactics persist evolutionarily in systems where there are low environmental effects on sexually selected phenotypes.
d
What is evolution? a) Change in the phenotypes of individuals in a population during reproduction. b) Frequent changes in allele frequencies that occur within a single generation. c) Developmental changes that occur within a population resulting in phenotypic differences among offspring. d) Any change in the heritable traits within a population across generations. e) All of the above
d
When both drift and selection are acting on a locus, which of the following can occur? a) Natural selection can increase the strength of genetic drift. b) Neutral mutations are subject to natural selection. c) Genetic drift can result in heterozygote advantage. d) Beneficial mutations can be lost from the population.
d
Which of the following are true? a) Coevolution of host and parasites affect the action of Muller's Ratchet. b) High heritability means a trait will evolve to have high fitness c) Domestication focuses on small populations and non natural traits and therefore cannot inform studies of genetic or phenotypic evolution. d) Heritabilities are population specific because environmental effects and allele frequencies can vary from place to place. e) All of the above.
d
Which of the following can NOT be a fitness enhancing strategy? a) Killing the offspring of rival males to bring females into receptivity more rapidly. b) Aborting fetal development when the offspring will have low fitness, either because of low paternal quality or low chances of survival, and reproducing again later. c) Foregoing one's own reproduction and investing in the reproduction of close relatives. d) Reducing linkage disequilibrium as a way of circumventing antagonistic pleiotropy. e) Accuring fitness losses by natural selection that are outweighed by fitness gains through sexual selection.
d
Which of the following can be a fitness enhancing strategy? a) Reducing linkage disequilibrium as a way of circumventing antagonistic pleiotropy. b) Augmenting the cost of males with Muller's Ratchet. c) Converting additive genetic variation to epistatic variation through inbreeding in variable environments. d) Killing the offspring of rival males to bring females into receptivity more rapidly. e) All of the above.
d
Which of the following is important for the Hamilton Zuk Hypothesis to explain the basis of mate choice based on a particular trait? a) That individuals with inferior genotypes assume alternative mating tactics. b) That the choosey sex prefer individuals with particular values of the trait, but that these not relate to fitness in any other way. c) Stabilizing selection resulting from a compromise between natural and sexual selection. d) That the trait be an honest indicator of resistance to pathogens or parasites. e) None of the above.
d
Which of the following statements about natural selection is NOT true? a) Natural selection acts on individuals, but its consequences occur in populations. b) Natural selection acts on phenotypes, but evolution consists of changes in allele frequencies. c) Natural selection adapts populations to conditions in the current environment, not the future. d) Natural selection is random.
d
Which of the following will contribute to antigenic drift? a) Blood sucking vectors of disease that bite many different species of animals. b) Intimate contact, such as the sharing of living spaces, between different host types. c) When an infected host of one species bites an individual of another species. d) Small, stepwise changes to viral epitopes. e) When a single host is infected by more than one type of virus. f) Reduced telomerase function in vectors.
d and f
Asexual reproduction a) is good because it increases linkage disequilibrium. b) is good because it decreases linkage disequilibrium. c) produces drift under Muller's Ratchet. d) is favored in fluctuating environments due to negative frequency dependent selection imposed by red queen dynamics. e) avoids the main costs of sex.
e
Selection acts more efficiently on alleles that have effects early in life relative to those that have effects late in life because : a) early acting alleles increase fitness whereas late-acting alleles increase senescence. b) heritabilities are stronger early in life, before environmental effects obscure the resemblance between parents and offspring. c) life history evolution increases with age, producing inconsistent relationships between phenotypic and reproductive variation. d) altruistic behaviors by relatives can raise indirect fitness, compensating for the negative fitness effects of deleterious mutations on the young. e) early acting alleles impose their effects before most reproduction has occurred.
e
Which of the following are false? a) In the short term, close physical proximity will produce correlated responses to selection at physically linked loci. b) Heritabilities are population specific because environmental effects and allele frequencies can vary from place to place. c) The need to find a mate, potential exposure to sexually transmitted diseases and risks of hybridization are all relatively unimportant costs to the evolution of sexual reproduction. d) Sexual selection imposes conflicts among kin when altruism is strong. e) Most patterns of selection alter the phenotypic mean initially in large part by reducing the variance.
e
Which of the following are true? a) In the short term, close physical proximity will produce correlated responses to selection at physically linked loci. b) In the short term, close physical proximity will produce correlated responses to selection at physically linked loci. c) Heritabilities are population specific because environmental effects and allele frequencies can vary from place to place. d) The need to find a mate, potential exposure to sexually transmitted diseases and risks of hybridization are all relatively unimportant costs to the evolution of sexual reproduction. e) All of the above.
e
Which of the following diseases is most likely to be eliminated from the human population by natural selection? a) Alzheimer's disease, a largely genetically-based neurodegenerative disease with average age of onset of 65. b) Coronary heart disease, currently the leading cause of death in the US, a disease largely caused by environmental factors. c) Syphilis, a sexually transmitted bacterial disease. d) Cystic fibrosis, a disease caused by recessive mutations in the CFTR gene; average age of diagnosis is 6 months. e) Myotonic dystrophy, a dominant autosomal neuromuscular disorder caused by mutations in the DMPK gene; can manifest at any age.
e
Which of the following equations can be used to test whether a population is in Hardy-Weinberg equilibrium? a) p2+2pq+q2=1 b) p+q=1 c) dN/dS=1 d) s<1/2N e) None of the above
e
Which of the following statements about linkage disequilibrium are false? a) Linkage disequilibrium can make the evolutionary fate of alleles at linked loci nonindependent. b) Linkage disequilibrium can result from physical proximity between loci. c) Linkage disequilibrium can be caused by epistasis for fitness. d) Linkage disequilibrium can increase or decrease fitness. e) Linkage disequilibrium breaks Muller's Ratchet.
e
In the Striped Stripey Fish, heritability for the size of a stripe on the tailfin is estimated from a population as h2 = 0.5. A change in the pattern of sexual selection in this environment favors a shift to a larger stripe, from the current average of 100mm to a new mean of 400mm. Using the breeder's equation R = h2S (where R is the response to selection and S is the selection differential), how many generations will the population take to get to the new optimum with a selection differential of 100mm? You can assume that the heritability does not change over time. a) based on the information given, you cannot calculate the answer. b) 1.5 generations. c) 3 generations. d) 4.5 generations. e) 5 generations. f) 6 generations. g) 7.5 generations. h) 9 generations. i) 10 generations. j) 10.5 generations. k) 12 generations. l) 15 generations.
f
Which are likely explanations for the evolution and maintenance of sexual reproduction? a) Frequency dependent selection b) Mate choice, including the Hamilton-Zuk Hypothesis c) Two parents provide a reproductive advantage over one d) Kin selection e) Estimates of the two-fold cost of sex are exaggerated, reducing the 'advantage' of asexual reproduction f) Recombination, reductional division, independent assortment and the fusion of gametes produce variation favored in complex or changing environments g) none of the above
f
The predicted high relatedness between female workers in haplodiploid social insects (e.g., r=0.75) was originally believed to favor altruism, explaining the evolution of eusociality in these systems. Of the factors below, which might explain why this hypothesis is incorrect? a) Workers distort sex ratio of young. b) Linkage disequalibrium means the expression Br-C > 0 cannot be satisfied. c) Females are forced into cooperative breeding by 'selfish' parents. d) All of the above. e) A and C only. f) B and C only. g) None of the above.
g
Consider a locus with exactly three alleles in a population, A1, A2, and A3. If the frequency of A1 is p, the frequency of A2 is q, and the frequency of A3 is r, then p+q+r = a) 1.0 b) 0.5 c) 3.0 d) 3p e) pqr
a
Genes specifying bitter taste receptors on our tongues have been shown to be polymorphic in many populations. The taste receptor 16 gene is polymorphic for a C or T at site 161 in the San population of Africa. 50 individuals were genotyped with the following outcome: 38 CC, 10 CT, and 2 TT. What is the frequency of the C allele in this population? a) 1.00 b) 0.86 c) 0.14 d) 0.50 e) 0.96
b
Investment in current reproduction at the expense of future reproduction is an example of : a) negative genetic correlation. b) pleiotropy. c) Dobzhansky Muller trade-off. d) a life history trade-off. e) epistasis
d
Which of the following evolved first? a) mammals b) flight c) photosynthesis d) eukaryotes e) land plants
c
Indirect fitness : a) is the reproductive success an individual gains accidentally, by misallocating reproductive effort outside the range of an optimum strategy. b) is less important than direct fitness. c) is the fitness females gain by consuming highquality nuptial food gifts from males. d) can contribute more to an individual's reproductive success than direct fitness. e) is the reproductive success an individual gains through their own reproduction.
d
The cost of males refers to what? a) The two-fold expense of males that results from genome dilution. b) Physiologically expensive male traits subject to sexual selection (such as a widowbird tail). c) Resistance to recombination in the heterogametic sex. d) The lower spread of a sexually producing genotype relative to an asexual genotype caused by the need for sexuals to make males. e) energy required to develop testes.
d
Scientific evidence for biological evolution comes from: a) observations of evolution in real time in natural populations. b) transitional forms in the fossil record. c) experimental manipulations conducted to determine the strength and pattern of selection in nature. d) comparative genomics. e) phylogenetic and biogeographic patterns in trait evolution. f) domestication. g) Each of the above brings complementary support to the fact that life evolves over time.
g
Which of the following are true statements? a) Evolution by natural selection is a natural consequence of there being heritable variation in fitness. b) Linkage disequilibrium occurs only when loci are on the same chromosome. c) The paradox of sex addresses why males cause genome dilution. d) The criteria for demonstrating that a trait is an adaptation are narrow, and thus so too are the methods that can be used to test for adaptations. e) All of the above are true statements.
A
Which of the following can NOT be a fitness enhancing strategy? a) Killing the offspring of rival males to bring females into receptivity more rapidly. b) Aborting fetal development when the offspring will have low fitness, either because of low paternal quality or low chances of survival, and reproducing again later. c) Foregoing one's own reproduction and investing in the reproduction of close relatives. d) Converting additive genetic variation to epistatic variation through inbreeding in variable environments. e) Accuring fitness losses by natural selection that are outweighed by fitness gains through sexual selection.
A