exam questions

Genome sizes in eukaryotes: Correlates with complexity, with more complex organisms always having smaller genomes and fewer protein coding genes. Correlates with complexity, with more complex organisms always having larger genomes and more protein coding genes. Does not correlate with complexity, and eukaryotes have highly varying quantities of protein-coding genes. Does not correlate with complexity, but most eukaryotes have approximately the same quantity of protein-coding genes and greatly varying quantities of non protein-coding genes. Does not correlate with complexity, but most eukaryotes have the greatly varying quantities of protein-coding genes and approximately the same quantity of non protein-coding genes.

.Does not correlate with complexity, but most eukaryotes have approximately the same quantity of protein-coding genes and greatly varying quantities of non protein-coding genes.

How many generations of non-evolution and random mating are required for a population to achieve Hardy-Weinberg Equilibrium? 1 10 100 Depends on the population size Depends on the initial allele frequencies Depends on the initial genotype frequencies Depends on the strength of selection

1

Which of the following models of sexual selection may result in phenotypes that are not beneficial or even disadvantageous to the survival of the organism on which it acts? Direct benefits Good genes (with the handicap principle) Runaway selection Sensory bias All of the above None of the above

All of the above

Which is NOT one of the three conditions that must be met for evolution by natural selection (adaptive evolution) to take place? Variation in phenotypic traits must exist in the population. Differential survival or reproductive success: differences in phenotype influence the probability of survival or reproduction. Inheritance: Differences in phenotypic traits must be at least partially heritable. All of the above are necessary for evolution by natural selection. None of the above are necessary for evolution by natural selection.

All of the above are necessary for evolution by natural selection.

The biological species concept is popular, intuitive, and well-known, but has many limitations. Which of the following are NOT limitations that apply to this species concept? Not applicable to fossil species Not applicable to asexual organisms Not applicable to species that hybridize easily All of these limitations apply to the biological species concept None of the these limitations apply to the biological species concept

All of these limitations apply to the biological species concept

If a population is in Hardy-Weinberg equilibrium, which of the following statements is correct? (Select one or more as applicable.) Each allele will be present at a 50% frequency. Allele frequencies can vary from generation to generation, but the average frequency must remain constant. The size of the population must remain constant from generation to generation. Allele frequencies must remain the same from generation to generation. The rate of change of allele frequencies must be greater than 1 percent from generation to generation.

Allele frequencies must remain the same from generation to generation.

Sexual reproduction can speed the spread of adaptations in a population because Males and females must travel to locate each other, thereby spreading their genes more broadly. Sexually transmitted diseases reduce fitness of individuals. Recombination can lead to novel genotypes. Beneficial mutations can be combined and harmful mutations can be purged. None of the above.

Beneficial mutations can be combined and harmful mutations can be purged.

The two fundamental components of the speciation process are: Selection of traits that increase mating success rather than survival, as well as evolution of anisogamy. Disruption of gene flow and evolution of reproductive isolation. Inheritable variation in phenotypes and associated differential reproductive success. All of the above. None of the above.

Disruption of gene flow and evolution of reproductive isolation.

Which of the following selection types increases the variation in a population: Stabilizing selection Directional selection Disruptive selection Purifying selection None of the above

Disruptive selection

Complex traits typically Evolve gradually through multiple cycles of adaptation and exaptation Do not necessarily always serve their current function over evolutionary time Are not very useful in their earlier, less complex or intermediate, forms Are difficult to explain by natural selection alone

Evolve gradually through multiple cycles of adaptation and exaptation Do not necessarily always serve their current function over evolutionary time

The "sensory bias" model of female mate choice is a model where: Females choose mates for traits that reflect better fitness and resistance to disease Females choose mates for the attractiveness of their offspring Females choose mates due to a pre-existing preference for particular traits Females choose mates based on their experiences with them in previous mating cycles

Females choose mates due to a pre-existing preference for particular traits

Which of the following evolutionary processes has a greater effect in smaller populations? Natural selection Genetic drift Non-random mating Substitution Artificial selection

Genetic drift

Which of the following processes can cause a beneficial or advantageous allele to be removed and lost from a population? (Select one or more as applicable.) Positive selection Negative selection Migration Genetic drift Background selection Hitch-hiking

Genetic drift Background selection

What does the Hardy-Weinberg model predict? The rate of change of allele frequencies under evolution. Genotype frequencies from allele frequencies under some assumptions. The direction of evolution in future generations. The genotype-by-environment variation interactions of a population. The fitness of a genotype given some assumptions .

Genotype frequencies from allele frequencies under some assumptions.

Which is the most likely order of events that could lead to allopatric speciation (select one or more as applicable)? Genetic divergence, then geographic separation, then reproductive isolation. Genetic divergence, then reproductive isolation, then geographic separation. Geographic separation, then genetic divergence, then reproductive isolation. Geographic separation, then reproductive isolation, then genetic divergence.

Geographic separation, then genetic divergence, then reproductive isolation.

Instead of competing by size or ornamentation with dominant males in male-male competition, a "sneaker male" adopts an alternate evolutionarily successful strategy, in which a male: Has a phenotype that is able to challenge and win direct conflicts with dominant males. Has a phenotype that resembles a female, and thus avoids challenge or conflict by dominant males when visiting females. Has a smaller and more agile phenotype to slip past dominant males undetected when visiting females. Has a phenotype with the appearance of a toxic/dangerous organism to fool dominant males when visting females.

Has a smaller and more agile phenotype to slip past dominant males undetected when visiting females.

Which of the following are the advantages of asexual reproduction over sexual? Easier for lineages to adapt to new environments Higher productivity for the same investment Higher levels of genome-scale mutations Immune to antibiotic resistance Not found in Eukaryotes

Higher productivity for the same investment

A simple survey of natural organisms today shows a range of complexities of functioning eyes, from extremely simple/reduced eyespots and reflecting pigment cups, to the much more complex single-lens chambered eyes and compound eyes. What is problematical about considering the vertebrate single-lens chambered eye the "pinnacle of evolution"? In terms of functionality, every form of the eye, from simple to complex, serves its required function. There are better or more complex eyes than the vertebrate one. Simple eyes could have arisen by chance alone but not more complex ones. All of the above.

In terms of functionality, every form of the eye, from simple to complex, serves its required function. There are better or more complex eyes than the vertebrate one.

Which of the following are NOT capable of evolving? Individual organisms. Populations. Species. Lineages Genera.

Individual organisms.

Which of the following are NOT capable of evolving? Individual organisms. Populations. Species. Lineages. Genera.

Individual organisms.

The mating system is a big factor in determining the type and intensity of sexual selection, which in turn can determine the level of sexual dimorphism. Which of the following mating systems is associated with the lowest level of sexual dimorphism? Monogamy Polygyny Polyandry Polygynandry Polyphyletic

Monogamy

Which of the following evolutionary processes has a greater effect in larger populations? Natural selection Genetic drift Non-random mating Substitution Artificial selection

Natural selection

Which of the following evolutionary processes will always increase the average fitness of a population as long as there is genetic variation? Natural selection Genetic drift Non-random mating Migration Mutation

Natural selection

Which of the following evolutionary processes changes allele frequencies in a population? (Select one or more as applicable.) Natural selection Genetic drift Migration Non-random mating Mutation

Natural selection Genetic drift Migration Mutation

1. Which of the following relationships cannot be read on a phylogeny? Sister relationships Ancestor-descendent relationships Parent-child relationships Natural selection relationships Shared ancestry relationships

Natural selection relationships

Which of the following are NOT a fundamental assumptions of the Hardy-Weinberg model predictions? No mutation No selection No migration No genetic drift No gene flow Infinite population size Random mating No genotype frequency changes No allele frequency changes

No genotype frequency changes

Which of the following evolutionary processes changes genotype frequencies in a population but not allele frequencies? (Select one or more as applicable.) Natural selection Genetic drift Migration Non-random mating Mutation

Non-random mating

Which is NOT one of the three conditions that must be met for evolution by natural selection to take place? Variation in phenotypic traits must exist in the population. Differences in phenotype influence the probability of survival or reproduction. One extreme of the phenotype leads to greater survival in the future. Differences in phenotypic traits must be at least partially heritable

One extreme of the phenotype leads to greater survival in the future.

Regarding the nature of natural selection, which of the following is NOT an accurate statement? Populations evolve traits by natural selection that will be useful for future environmental changes. Natural selection acts on the phenotypes of individuals, but evolution occurs with changes in allele frequencies in populations. Natural selection can and does produce features that are less than perfect adaptations. Natural selection operates as a systematic, nonprogressive mechanism.

Populations evolve traits by natural selection that will be useful for future environmental changes.

AZT, while initially very successful in treating AIDS by limiting the replication of the HIV virus in a patient eventually loses its effectiveness, due to the HIV population in the patient evolving resistance. Which of the following is a correct characterization of the process? Following exposure to AZT, a mutation arose in viral genomes as a natural response to overcome the treatment. Resistance to AZT evolved in the population as a result of any virus lineages with a mutation that conferred resistance being able to continue to successfully replicate in an environment with AZT, increasing in frequency until they constituted most of the virus population. HIV progresses naturally from non-AZT resistant to AZT resistant forms as it evolves, with the AZT-resistance variant being more highly evolved and being much more infectious. a and c. b and c All of the above.

Resistance to AZT evolved in the population as a result of any virus lineages with a mutation that conferred resistance being able to continue to successfully replicate in an environment with AZT, increasing in frequency until they constituted most of the virus population.

In populations where individuals with intermediate values of a trait have the highest fitness, the average value of the trait does not change over time, but the variation tends to be reduced. This set of circumstances is known as: Stabilizing selection Directional selection Disruptive selection None of the above

Stabilizing selection

Which of the following selection types increases the population fitness over time (select one or more than one as appropriate): Stabilizing selection Directional selection Disruptive selection Purifying selection None of the above

Stabilizing selection Directional selection Disruptive selection Purifying selection

Which of the following characters are neither (currently) adaptive or exaptive? The color of blood cells. The oxygen-binding properties of blood cells. The presence of lungs in some modern fishes. The waxy cuticle of cacti.

The color of blood cells.

Which is an example of anisogamy? Male red deer have large antlers, but females do not have antlers at all. Female jacanas are larger in size than the males. Female fiddler crabs have two small claws, but males have one small claw and one huge claw. The eggs of a female kiwi are large, but the sperm of the males are small. None of the above.

The eggs of a female kiwi are large, but the sperm of the males are small.

Which of the following best describes the "Red Queen" hypothesis? Investment in sperm production is mostly wasted. Adaptive evolution is accelerated due to breaking of linkage disquilibrium. The evolution and maintenance of sex is in response to a host-parasite arms-race. In the absence of genetic recombination due to e.g., sexual reproduction, deleterious mutations will accumulate in an irreversible manner (linkage disequilibrium) There are trade-offs between the costs and benefits of sexual reproduction.

The evolution and maintenance of sex is in response to a host-parasite arms-race.

Which of the following is an example of a vestigial character? The use red-colored hemoglobin to transport oxygen in some lineages of animals. The hip bones of whales. The lack of teeth in birds. The wings of penguins. The amniotic egg of mammals.

The hip bones of whales.

A new pest insect species has started attacking plant crops around San Jose. Fortunately, there is a possibility that a new pesticide might be effective. There is a danger, of course, that application of the pesticide may lead to evolution of pesticide resistance in the insects. Which of the following need to be true for this to occur (select one or more than one as appropriate):? The population must currently have some individuals that are pesticide resistant. Pesticide resistance must be exaptive. Pesticide resistance must be inheritable. None of the above.

The population must currently have some individuals that are pesticide resistant. Pesticide resistance must be inheritable.

Which of the following is an example of an exaptive character? The use of respiratory organs (lungs) as buoyancy control organs (swim bladders) in some fishes. The use of scales as body armor/defenses in some reptiles. The use of simple "eye spots" to sense light without forming an image (to, e.g., calibrate circadian rhythyms in some unicellular organisms). The use of lenses to focus light in vertebrate eyes. The use blue-colored hemocyanin to transport oxygen in some lineages of animals.

The use of respiratory organs (lungs) as buoyancy control organs (swim bladders) in some fishes.

What does it mean when we say evolution is "pluralistic"? Evolution produces many lineages. Many types of biological observations can be explained by evolution. There are many different mechanisms or ways by which evolution works. There are many types of different characters in evolution. Evolution can result in many different forms.

There are many different mechanisms or ways by which evolution works.

Which of the following are advantages of a natural classification scheme that captures the evolutionary history of organisms (select one or more as applicable): We can predict or model characteristics of ancestors or lineages within a clade We can identify species boundaries that may disrupt gene flow We can avoid the evolution of antibiotic or other treatment resistence in pathogens We are able to reduce the rate of deleterious mutations in our genomes We can distinguish between different species in hybrid zones

We can predict or model characteristics of ancestors or lineages within a clade

Which of the following is one of the circumstances under which protoandrous sequential hermaphroditism is observed (assuming correlation of body size with age)? When it is advantageous to be male when larger, as you can win conflict with other males in competition for access to mates, but advantageous to be female when smaller, as then while you are not competitive in conflicts, you can still continue to reproduce without challenging. When it is very advantageous to be female when larger, due to the greater number of eggs carried, but male when smaller, as large numbers of sperm can still be produced even when small. When contact with other members of your species is very rare, so some flexibility in being one sex or another is very advantageous so all contacts can result in productive matings. When there is a shortage of males in the environment meaning that if you can facultatively become male in this conditions, you have will have a significant reproductive advantage.

When it is very advantageous to be female when larger, due to the greater number of eggs carried, but male when smaller, as large numbers of sperm can still be produced even when small.

Which of the following is a major difference between vicariant vs. dispersal allopatry? the gene flow disruption is permanent in vicariant allopatry, but can be ephemeral in dispersal allopatry (fluctuating with ice ages or the rise and fall of sea levels). the gene flow disruption is due to a physical barrier in vicariant allopatry, but is behaviorial or ecological in dispersal allopatry a physical barrier to gene flow disruption emerges to fragment an ancestral population in vicariant allopatry, but organisms move over pre-existing physical barrier in dispersal allopatry all of the above

a physical barrier to gene flow disruption emerges to fragment an ancestral population in vicariant allopatry, but organisms move over pre-existing physical barrier in dispersal allopatry

Which of the following models of gene flow disruption involves physical barrier which prevents gene flow between populations? allopatric sympatric parapatric All of the above None of the above

allopatric

The phenotypic variation in a population is the result of: genetic variation environmental variation genotype-by-environment variation can be any of the above none of the above

can be any of the above

Which of the following is NOT fundamentally required for all and any type of evolution by natural selection? inheritance differential survival and reproductive success environment-by-genotype source of phenotypic variation standing inheritable variation

environment-by-genotype source of phenotypic variation

Birds, like mammals, are "warm-blooded" (endothermic homeotherms), yet their closes living relatives, crocodiles, are "cold-blooded" (ectothermic poikliotherms). Warm-bloodedness evolved independently in birds mammals, and we refer to this type of similarity as: homoplasy homology orthology ortholasy

homoplasy

Which of the following types of evolution requires and acts on phenotypic variation: mutation natural selection genetic drift migration all of the above none of the above

natural selection

Which of the following types of evolution results in adaptive evolution? mutation natural selection genetic drift migration all of the above none of the above

natural selection

Which of the following types of evolution, if strong enough relative to other evolutionary forces, results in the fixing of beneficial alleles in the population? mutation natural selection genetic drift migration all of the above none of the above

natural selection

If two organisms of different species successfully reproduce an offspring, but that offspring turns out to be infertile, this would be the result of: prezygotic isolating mechanisms postzygotic isolating mechanisms polyploidy hybrid speciation speciation by hybridization

postzygotic isolating mechanisms

Factors such as behavioral, temporal, or ecological isolation mechanisms that prevent two closely related sympatric populations from interbreeding can be grouped together and classified as: prezygotic isolating mechanisms postzygotic isolating mechanisms polyploidy hybrid speciation speciation by hybridization

prezygotic isolating mechanisms

The patterns of phenotypes an individual may develop upon exposure to different environments is called its: predictability norm variability norm response norm reaction norm

reaction norm

Evolution by natural selection: requires that multiple unverified assumptions are made before it can be considered a viable explanation is only a theory and therefore not testable can be tested observationally and experimentally can be observed but cannot be tested experimentally is the only known mechanism of adapative evolution

requires that multiple unverified assumptions are made before it can be considered a viable explanation