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A new mutation in a population of birds appears. It gives individuals a slight advantage in spotting predators and a fitness advantage. If those that have the mutation have 0.5% greater fitness than those without, what is the probability that the mutation will spread and eventually become fixed? A. 2% B. 0.5% C. 1% D. 100% ---------CORRECT ANSWER-----------------C Why did industrial melanism in the peppered moth, help convince researchers that the intensity of natural selection can be very strong? A. Birds were unable to prey on the moths once they acquired their color adaptations. B. The dark-colored morph drove the light-colored morph to extinction C. The dark-colored allele increased in frequency very rapidly in multiple populations and later decreased rapidly after the environment changed. D. The moth population exploded, covering England with moths during the Industrial Revolution ---------CORRECT ANSWER-----------------C In hypotheses about _____________ evolution, individuals acquire variation in phenotype during their lives that are passed to offspring, whereas in ______________ evolution, individuals inherit variation from their parents and differ in survival and reproductive rate thereby changing relative proportions of phenotypes from one generation to another. A. Variational evolution, Lamarckian evolution
B. Transformational evolution, Variational evolution C. Transformational evolution, Lamarckian evolution D. Variational evolution, Transformational evolution ---------CORRECT ANSWER-----------------B Which of the following represents evidence used to support the theory of evolution A. Evidence from the fossil record B. All of these C. Age of the Earth D. Evidence of common ancestry ---------CORRECT ANSWER----------------- B The diversification of a small group of ancestral species into a large number of descendant species living in a diversity of new habitats is referred to as... A. Cladogenesis B. Phyletic gradualism C. Adaptive radiation D. Diversity to disparity ---------CORRECT ANSWER-----------------C Gene trees may be inconsistent with phylogenies of species generated from other independent data when.. A. Multiple methods of phylogenetic analysis are used to analyze the data. B. More closely related, derived alleles among several alleles at a locus in an ancestral population become fixed in different species C. The number of variants of a gene is less than 3 D. The common ancestral species has a small population size --------- CORRECT ANSWER-----------------B
C. Selection increases the complexity of HIV response to drug therapy D. Of a combination between the ineffectiveness of the drug and the natural populations dynamics of HIV once it has infected a host --------- CORRECT ANSWER-----------------B Allometry is the phenomenon by which: A. During ontogeny an organism grows different parts of an organism at different rates B. Different species grow more rapidly than others in the same lineage C. Different measures are used for different parts of an organism D. A measure is derived of allelic variation in populations ---------CORRECT ANSWER-----------------A Once the historical relationships among different variant DNA sequences are inferred, it is possible to A. Construct gene trees (gene genealogies) B. Determine the holotype of a species C. Perform bootstrap analysis D. Determine the location of introns in a gene ---------CORRECT ANSWER- ----------------A Which trait cannot describe an adaption? A. A heritable behavioral trait that does not involve physical morphology, like cooperation B. A trait that promotes reproduction but does not affect survival, like floral scents C. A trait that appears to have been designed following engineering principles, like the extendable jaws of a snake D. A trait that does not change the probability of survival or reproduction, like the color of cave-dwelling fish ---------CORRECT ANSWER----------------
A change in which variable would not necessarily change an organism's fitness? A. Mating success B. Mutation rate C. Viability D. Fertilization success ---------CORRECT ANSWER-----------------B Phenotypic variance that is not due to genetic variance can be attributed to A. Pleiotropy B. Environmental variance C. Dominance D. Epistasis ---------CORRECT ANSWER-----------------B Vestigial structures are considered evidence supporting the theory of evolution because: A. These functionless, reduced structures in one taxon serve an important function in closely related taxa B. They appear during development in all organisms in a lineage C. Pseudogenes give rise to these structures D. They demonstrate natural selection favoring small size structures --------- CORRECT ANSWER-----------------A Assume a population of 1000 individuals that is in Hardy-Weinberg equilibrium with respect to a genetic locus of interest that has 3 alleles. If there are 125 AA, 400 BB, 75 CC, 170 AB, 135 BC, and 95 AC in year 2005, what will the frequencies of alleles p, q, and r be in the year 2009 assuming the population stays in H-W equilibrium? Let p = freq of A, q = freq of B and r = freq of C.
D. Often accumulate mutations because selection is relaxed on the duplicated copy ---------CORRECT ANSWER-----------------A Assume a single, randomly mating 2-allele (A1A2) locus, and consider a 2- dimensional plot (avg fitness on ordinate vs. freq of A1 allele on abcissa) of an adaptive landscape of this locus in which average fitness is maximized when A1= 0.33 in order to answer the following question: Which is the correct rank order of fitnesses of the genotypes? (highest to lowest, left to right) A. A2A2, A1A1, A1A B. A1A1, A2A2, A1A C. A1A2, A2A2, A1A D. A1A2, A1A1, A2A2 ---------CORRECT ANSWER-----------------C Given the following frequencies for alleles at a single locus in a population of 321 individuals p=0.69, q=0.15, r=0.07, s=0.05, t=0.04. Rank the alleles in order to the probabilities that they will be fixed in the population. A. p,q,r,s,t B. p,s,r,q,t C. t,q,r,s,p D. It is random so each is equally likely to become fixed ---------CORRECT ANSWER-----------------A Given the equations below coupling natural selection and migration for estimating the frequency of the q allele in the recipient population: If the frequencies of q in the source and sink populations are similar, what do you infer about the rate of change of q as m approaches 0? Find equations A. Rate of change in q per generation is driven mostly by natural selection
B. Rate of change in q depends on population size C. Rate of change in q per generation is driven in approximately equal proportions by selection and migration D. Rate of change in q per generation is driven mostly by migration E. q will no longer change - it has reached equilibrium FIND ANSWERS ---------CORRECT ANSWER----------------- Which of the following mechanisms of reproductive isolation represent post-zygotic barriers? A. Ecological inviability B. Hybrid sterility C. Behavioral sterility D. All of the mechanisms listed E. Hybrid inviability ---------CORRECT ANSWER-----------------D "Good genes" models of sexual selection via female choice should include which of the following? A. Offspring of the most ornamented males will have performance/fitness advantages over offspring of less ornamented males B. Females receive direct benefits from ornamented males in the form of food, protection, or parental care of their young C. Females should have pre-existing sensory biases for parental care in males D. The quality of males ornamentation is a reliable indicator of his genetic quality and offspring of ornamented males will have enhanced fitness, whereas females are neither receiving direct benefits from males, nor do they have sensory bias for the existence of parental care in males E. The quality of male ornamentation (song, color, behavioral display, etc.) is correlated with his genetic quality. ---------CORRECT ANSWER------------- ----D
You observe a very narrow cline in the middle of a broadly distributed species' range. From this you could conclude that A. Either selection is strong or migration variance is low B. Migration variance is low C. Migration variance is high D. Either selection is strong or migration variance is high E. Selection is strong ---------CORRECT ANSWER-----------------A In which situation will gene swamping prevent local adaptation? A. Gene flow is high and the patch favoring the alternative allele is small. B. The adaptive trait varies quantitatively and is controlled by several gene loci C. Selection is strong and migration is low D. Selection and migration are both very low in magnitude E. Selection and migration are both very high in magnitude --------- CORRECT ANSWER-----------------A Rare alleles are likely to be lost from the population due to genetic drift causing a reduction in heterozygosity in the population according to the following equation: Consider two populations, one (A) with an initial heterozygosity of 0.5 and 12 individuals, the other (B) with an initial heterozygosity of 0.35 and 100 individuals. Which population will be less genetically diverse after 10 generations? FIND EQU. A. A B. Cannot be estimated given the information provided C. B D. They will be equally heterozygous after 3 generations FIND ANSWER ---------CORRECT ANSWER-----------------A
Two individuals in an asexual population have distinct, beneficial mutations. When their descendants compete with each other, one of those mutations is lost to extinctions. This phenomenon is called A. The twofold cost of males B. Selective interference C. Bateman's principle D. Clonal interference E. Fisher's runaway. ---------CORRECT ANSWER-----------------D In which situation will gene swamping prevent local adaptation? A. The adaptive trait varies quantitatively and is controlled by several gene loci. B. Selection and migration are both very low in magnitude C. Gene flow is high and the patch favoring the alternative allele is small D. Selection and migration are both very high in magnitude E. Selection is strong and migration is low ---------CORRECT ANSWER------ -----------C Consider gene locus having 4 alleles in a population of 100 individuals. Imagine that when studying this locus you observe declines in both mean fitness and heterozygosity at a consistent rate. What do you infer as to the cause of these trends? A. Migration of new alleles into the population B. Extinction of new mutations in the population C. a combination of selection and infrequent inbreeding D. loss of low frequency advantageous allele via genetic drift E. Disruptive selection against heterozygotes FIND ANSWERS ---------CORRECT ANSWER-----------------A
A. Less reproductive isolation among populations that share similar habits B. More reproductive isolation among populations that share similar habitats C. No reproductive isolation D. Complete reproductive isolation among all populations E. Reproductive isolation that is independent of habitat type --------- CORRECT ANSWER-----------------A If access to females limits male reproduction, we might expect: A. Females to compete for males B. Males to be very selective among potential mates C. Males to compete for access to females, or resources females require and have weapons and/or be larger than females are both likely, whereas selectivity of mates among males and females competing for males are less likely D. Males to compete for access to females, or resources females require E. Males to have weapons and/or be larger than females ---------CORRECT ANSWER-----------------C Muller's ratchet may operate in asexually reproducing populations because A. sexually reproducing populations do not have genetic load B. Linkage disequilibrium due to drift eliminates the zero deleterious mutation class C. mildly deleterious mutations are masked in diploid organisms D. Of rapid population growth rate, asexual populations are larger and mutate faster ---------CORRECT ANSWER-----------------B The Dobzhansky-Muller theory of epistasis implies which of the following? A. Populations are adapted to different environments, but hybrids formed between them lie in an adaptive valley for those environments, but not necessarily to other environments
B. none of these choices C. Reinforcement was incomplete allowing hybrid formation D. Different populations become fixed for different incompatible alleles so that neither populations produces heterozygotes of poor fitness, but hybrids between populations do E. The homogametic sex is the less viable one in hybrid formation --------- CORRECT ANSWER-----------------D The inbreeding coefficient, f, measures the degree to which relatives mate more frequently than they otherwise would in a randomly mating population. Decreasing values of fare associated with A. A decline in frequency of dominant phenotypes, and an increase in recessive homozygotes that causes inbreeding depression (decline in fitness/increase in genetic load) B. no change in heterozygosity in the populations because a single generation of random mating will restore the heterozygote genotypes C. Decreased fitness by eliminating inferior heterozygote genotypes D. An increase in heterozygotes genotypes and decreases in homozygote genotypes E. A decline in frequencies of all genotypes associated with inbreeding depression FIND ANSWERS ---------CORRECT ANSWER----------------- If genetic drift is principal, or only, evolutionary process affecting allele frequencies at a gene locus, then which of the following is true? A. Large populations maintain more genetic variation than small ones B. all of these are true C. Large populations generate more genetic variation than small ones D. Mutations drift toward fixation more slowly in large populations E. Substitutions occur at the same rate in populations of all sizes FIND A ---------CORRECT ANSWER-----------------D
Which trait is most likely a product of sexual selection by female choice? A. Barbs on the penis remove the sperm of rival males and increase probability of fertilization B. Bright coloration on a fish that is indicative of genetic quality C. Satellite male behavior by horseshoe crabs, in which an unmated male piggybacks onto a mating pair in the hopes of fertilizing at least a few eggs D. Stronger antlers on an elk that improves an individual's chances in combat E. Successful bedbugs with the ability to overcome the female's resistance to mating ---------CORRECT ANSWER-----------------B Consider a hypothetical locus with several segregating alleles. The populations size is small, mutation is absent, and none of the alleles has a selective advantage. Which of the following is likely to occur after a long period of time (many generations)? A. Allele frequencies will change over time, but all alleles will remain B. Genetic variation will decline as alleles randomly go extinct C. Allele frequencies will cycle over time D. Balancing selection will maintain all the alleles E. Allele frequencies will remain constant ---------CORRECT ANSWER------- ----------B The effective population size, Ne , represents an idealized, hermaphrodite, randomly mating population that A. Is equal to, or greater, in size to the censused populations size B. Exhibits the same strength of genetic drift as the actual, complex populations of interest C. Loses heterozygosity at a rate equal to the reciprocal of populations size D. Is equal in size to twice the number of generations since a mutant allele arose
E. Has no effect on the intensity of selection on a locus ---------CORRECT ANSWER-----------------B Sexual selection in flowering plants is most closely analogous to what mode of sexual selection in animals? A. Fisher's runaway process B. Perceptual bias C. Direct Benefits model D. Sperm competition E. Good genes mechanism ---------CORRECT ANSWER-----------------D The Nucleotide diversity a neutral locus between two populations equals 0.0004 and the mutation rate equal 10^-7 per bp at that locus. If the migration rate between these populations equals 0.001 what is the fraction genetic variance that differs between them (Fst)? A. 0. B. 0. C. 0. D. 0. E. 0.179 ---------CORRECT ANSWER-----------------B In a species with populations distributed continuously along an environmental gradient, the width of a cline for phenotype across the gradient is A. Is proportional to the selection coefficient B. Proportional to the square root of the ratio of migration variance divided by the selection coefficient C. Inversely proportional to the migration variance D. Is 2.5 times the migration variance and selection coefficient E. Is 2.5 times the selection coefficient ---------CORRECT ANSWER---------- -------B
The approximate time it takes for a neutral allele to either become fixed or lost from a populations, thereby reducing genetic diversity in the population is A. The number of years equivalent to the populations size B. none of these C. The coalescence time divided by 2 D. The number of generations equivalent to twice the effective populations size E. The number of generations equivalent to the population size --------- CORRECT ANSWER-----------------D Which observation would be the best evidence for a recent founder event or population bottleneck? A. Low genetic diversity in a single population of a widely distributed species B. Evidence that population size on an island is maintained by a steady influx of migrants from the mainland C. Roughly equal genetic variation in all subregions of a species range D. Evidence that a specific genotype has a strong selective advantage in an environment E. Census evidence for a steadily growing populations ---------CORRECT ANSWER-----------------A If reinforcement is an important means of completing speciation one expects to observe among a group of species that are compared with one another the following: A. Stronger postzygotic isolating mechanisms among parapatric relative to sympatric taxa that are that are of equivalent in age since time of divergence B. Stronger isolation in parapatric pairs of species at all levels of genetic distance
C. Stronger prezygotic isolating mechanisms among sympatric relative to allopatric taxa that are of equivalent in age since time of divergence D. Stronger postzygotic isolating mechanisms among sympatric relative to allopatric taxa are of equivalent in age since time of divergence E. Stronger prezygotic isolating mechanisms among parapatric relative to sympatric taxa that are of equivalent in age since time of divergence CHECK ---------CORRECT ANSWER-----------------A A monophyletic group (also called a clade) is defined as... A. The set of species derived from one common ancestor. B. Having shared ancestral character states C. Having shared derived character states D. A branch point in a phylogenetic tree ---------CORRECT ANSWER--------- --------A Which of the following is an example of homologous characters? A. Snails and turtles both have strong, hard shells for protection. B. Crocodiles and humans both have forelimbs with five digits C. Parrotfish and parrots (the birds) both have beaklike mouths. D. The aquatic larval stage was lost in a lineage of salamanders but was later regained. ---------CORRECT ANSWER-----------------B Gene genealogies can vary for different loci. What does this imply for species trees? A. Adaptive radiations do not occur. B. Species trees require apomorphies in order to be successfully resolved. C. All genes in the genome are subject to similar selective pressures D. Species trees should be constructed using multiple loci (both nuclear and mtDNA) ---------CORRECT ANSWER-----------------D
