Exam 1

phylogeny tree of plants

Green Algae Mosses Ferns Gymnosperm Angiosperm

What are Plants?

Mostly photosynthetic, multicellular eukaryotes Use chlorophylls a and b Cellulose cell wall Starch as storage product Mostly terrestrial Alternation of generations

phylogeny tree of plant characteristics

out of water vascular tissue seeds flowers

Coloration in the peppered moth (Biston betularia) is determined by a single gene with two alleles showing complete dominance. Dark moths are homozygous dominant or heterozygous for the gene, light moths are homozygous recessive. In a sample of 100 moths, you determine that 64 of the moths are dark. According to the Hardy-Weinberg rule, the expected frequency of the dominant allele is ____. A. 0.4 B. 0.36 C. 0.6 D. 0.64

A. 0.4

What is fitness? A. A measure of reproductive success B. The rate of survival of a species C. A measure of an animal's top speed D. A measure of the overall size of an individual

A. A measure of reproductive success

Darwin argued that: A. All organisms are descended from a common ancestor. B. Supernatural forces have shaped differences between species. C. Humans are the direct descendants of monkeys. D. Artificial selection lead to different species in nature.

A. All organisms are descended from a common ancestor.

The wings of birds and butterflies are examples of structures that resemble each other and have similar function, but are the result of convergent evolution in separate lineages. These structures are called ________. A. Analogous structures. B. Homologous structures. C. Vestigial structures. D. Embryonic structures. E. Homozygous structures.

A. Analogous structures

During a study session about evolution, one of your fellow students remarks, "The giraffe stretched its neck while reaching for higher leaves; its offspring inherited longer necks as a result." Which statement is most likely to be helpful in correcting this student's misconception? A. Characteristics acquired during an organism's life are generally not passed on through genes. B. Spontaneous mutations can result in the appearance of new traits. C. Only favorable adaptations have survival value. D. Disuse of an organ may lead to its eventual disappearance.

A. Characteristics acquired during an organism's life are generally not passed on through genes.

A biologist seeing a sign describing evolution as "just a theory" would think that... A. Darwin's theory is supported with a tremendous amount of evidence. B. Evolution is just a collection of facts without a central theme and this is not a theory. C. Evolution is what Darwin proposed to account for all the changes he observed in the finches so it is a hypothesis, not a theory. D. Evolution occurred in the past, but it is not occurring in the present, so it cannot be a theory.

A. Darwin's theory is supported with a tremendous amount of evidence.

Evolution is a _______. A. Fact B. Theory C. Hypothesis D. Conjecture

A. Fact

How would gene flow between two allopatric populations affect the chance of speciation? A. It would most likely decrease the chance of speciation B. It would probably increase the chance of speciation C. It would reinforce the separation of the species D. It would increase the likelihood of the development of post-zygotic isolating mechanisms

A. It would most likely decrease the chance of speciation

If we were able to provide a vaccine against malaria to everyone, what changes would you predict to the frequency of the sickle cell allele in the world's population? A. It would probably decrease. B. It would probably increase. C. No change; it would remain the same.

A. It would probably decrease.

Which of the following innovations was not involved specifically in the highly successful colonization of land by aquatic plants? A. Photosynthesis B. Cuticle C. Roots D. Vascular tissue

A. Photosynthesis

Which of the following statements about evolution is false? A. Scientists have not been able to observe evolution in action. B. Evolutionary theory can be applied to solve practical problems. C. Biologists have accumulated a large body of evidence about the evolutionary changes that have occurred in the past. D. Biologists have accumulated a large body of evidence about how evolutionary changes occur.

A. Scientists have not been able to observe evolution in action.

Natural selection varies the shape of the beaks among Darwin's finches in response A. To the available food supply B. To the available nest building material supplies C. To presence of ectoparasites on their feathers D. To the need to improve their feather preening abilities

A. To the available food supply

Which of the following was a key innovation specifically involved in the evolution of large trees like giant redwoods? A. Vascular tissues B. Flowers C. Fruit D. Coevolution with birds and insects

A. Vascular tissues

In most regions of Earth today, land flora consists predominantly of A. angiosperms B. gymnosperms C. ferns D. bryophytes

A. angiosperms

Adaptive radiation is best described as the existence of A. groups of closely related species recently evolved from a common ancestor. B. groups of distantly related species recently evolved from a common ancestor. C. groups of closely related species recently evolved from different ancestors through hybridization. D. individuals of closely related species that originated in different areas within diverse habitats, but that have rejoined as a single species.

A. groups of closely related species recently evolved from a common ancestor.

Characteristics that have arisen in organisms as a result of common evolutionary descent are said to be ______________ characteristics. A. homologous B. adaptive C. convergent D. ancestral

A. homologous

Which of the following phrases is not an essential part of the biological species concept? A. morphologically distinct B. reproductive isolation C. independent evolutionary unit D. actually or potentially interbreeding within species E. no gene flow with other species

A. morphologically distinct

Punctuated equilibrium refers to A. relatively little evolutionary change over long periods of time, interspersed with short periods of rapid change. B. the loss of large number of species, called mass extinctions. C. adaptive radiations on islands. D. the divergence of one species into two species.

A. relatively little evolutionary change over long periods of time, interspersed with short periods of rapid change.

The biological species concept proposed by Ernst Mayr emphasizes all of the following except A. significant hybridization between different species. B. production of fertile offspring within the species. C. natural populations. D. reproductive isolation from other species. E. interbreeding within the species.

A. significant hybridization between different species.

The California populations of the Northern elephant seal are descendants from a very small population of seals that was over-hunted in the 1890s. Heterozygosity in this population would be expected to be ________ due to _______________. A. slight; a bottleneck effect B. slight; the founder effect C. great; disruptive selection D. great; a bottleneck effect E. great; assortive mating

A. slight; a bottleneck effect

Over the long run, mutations are important to evolution because A. they are the original source of genetic variation B. once an allele is lost through mutation, another mutation to that same allele cannot occur C. most mutation rates are one in a thousand D. whether good or bad, mutations increase the fitness of an individual E. mutations are usually beneficial to the progeny

A. they are the original source of genetic variation

Which of the following examples would lead to allopatric speciation? A. The colonization of an island by a small subset of a mainland population B. A new river channel dividing a population of beetles into separation C. The extinction of a large proportion of a population leaving only distant sub-populations D. A lava flow flowing across the landscape that isolates one population from conspecifics

All of the above

If a population with two alleles is at Hardy-Weinberg equilibrium and the frequency of one allele is 0.7, what is the heterozygote frequency? A. 0.7 B. 0.42 C. 0.3 D. 0.21

B. 0.42

Suppose you have a population of flour beetles with 1,000 individuals. Normally the beetles are red; however, this population is polymorphic for a mutant autosomal body color, black, designated by b/b. Red is dominant to black, so B/B and B/b genotypes are red. Assume the population is in Hardy-Weinberg equilibrium, with equal frequencies of the two alleles. What is the phenotypic ratio? A. 0.5 red; 0.5 black B. 0.75 red; 0.25 black C. 0.25 red; 0.75 black D. 0 E. Insufficient information is given to answer the question

B. 0.75 red; 0.25 black

Which of the following is not a defining characteristic of plants? A. Photosynthetic B. Aquatic C. Cell wall made of cellulose D. Eukaryotic

B. Aquatic

Why is the sickle cell allele so prevalent in some parts of the world? A. Carrying two copies of the allele causes sickle-cell disease, which provides a selective advantage. B. Carrying one copy of the allele protects against malaria, common in those parts of the world. C. The allele arose by mutation in those parts of the world and never spread elsewhere. D. The presence of malaria caused the mutation that created the allele.

B. Carrying one copy of the allele protects against malaria, common in those parts of the world.

Similar habitats often place similar selection pressures on different species. This often leads to unrelated species having features in common. What is this an example of? A. Vestigial structures B. Convergent evolution C. Homologous traits D. Artificial selection

B. Convergent evolution

If sickle cell disease were caused by the presence of only a single copy of the sickle cell allele, what would you expect to happen to the frequency of the allele in places with a high incidence of malaria? A. Increase B. Decrease C. Remain the same

B. Decrease

Considering the overall human population of the U.S. mainland at the time when the slave trade brought large numbers of people from equatorial Africa, what was primarily acting to change the frequency of the sickle-cell allele in the overall U.S. population? A. Natural selection B. Gene flow C. Genetic drift D. Founder effect

B. Gene flow

Which of the following is false? A. Over the history of the Earth the overall trend is a steady increase in the number of species B. Mass extinctions appear to affect all types of species equally C. One of the extinctions resulted in a loss of half the species of plants and animals on Earth D. One of the mass extinctions may have been caused by an asteroid hitting Earth

B. Mass extinctions appear to affect all types of species equally

Which of the following is true about speciation on island archipelagos? A. Speciation is slow because it depends on emigration from the mainland. B. Most speciation occurs allopatrically. C. Ecological competition may cause new species to go extinct slowing speciation. D. Speciation by polyploidy is most common.

B. Most speciation occurs allopatrically.

Which of the following agents of evolution adapts populations to their environments? A. Mutation B. Natural selection C. Nonrandom mating D. Genetic drift

B. Natural Selection

Which of the following statements about hominin evolution is correct? As hominins have evolved A. Canine teeth have increased in size B. Sexual dimorphism was significantly reduced C. They have developed proportionally longer fingers D. Jaw size has increased

B. Sexual dimorphism was significantly reduced

Which of the following best describes natural selection? A. Chance variations in traits B. The differential survival and reproduction of individuals C. The processes that lead individuals to resemble their parents D. The potential for all species to increase rapidly in number E. The immutability of species

B. The differential survival and reproduction of individuals

Ginkgo trees occur in Asia and North America. Despite their geographic separation by the Pacific Ocean, biologists consider them the same species. What aspect of the biological species concept accounts for this? A. They are reproductively isolated B. They are potentially capable of exchanging genes C. They are exchanging genes across the ocean D. They have different evolutionary ancestries E. They have formed a large hybrid zone

B. They are potentially capable of exchanging genes

Birds, snakes, lizards, turtles, and crocodiles are all thought to share a common ancestor and several homologous traits. Assuming that this is true, this group of animals would best represent A. a polyphyletic group. B. a monophyletic group. C. homoplastic convergence. D. several clades. E. a species cluster.

B. a monophyletic group.

In a West African finch species, birds with large or small bills survive better than birds with intermediate-sized bills. The type of natural selection operating on these bird populations is _______ selection A. directional B. disruptive C. stabilizing D. nonrandom E. sexual

B. disruptive

Migration and hybridization between individuals of adjacent populations causes gene ______. A. blending B. flow C. mutation D. dominance

B. flow

To reproduce sexually, bryophytes, such as mosses, require A. small, non-showy flowers that are fertilized with pollen from another plant. B. free water external to the plant. C. high temperatures. D. insect pollination.

B. free water external to the plant.

A group is considered paraphyletic if A. all members of the group share a common ancestor. B. not all descendants of the common ancestor are included. C. the common ancestor of the group is not included in the group. D. the group does not contain the most recent common ancestor. E. it is the most parsimonious grouping.

B. not all descendants of the common ancestor are included.

A gene pool consists of all the alleles A. of an individual's genotype B. present in a specific population C. that occur in a species throughout its evolutionary existence D. that contribute to the next generation of a population

B. present in a specific population

Adaptive radiation is likely to produce several to many A. key innovations. B. species clusters. C. sterile hybrids. D. reproductive isolating mechanisms. E. races.

B. species clusters

Adaptive radiation is likely to produce several to many A. key innovations. B. species clusters. C. sterile hybrids. D. reproductive isolating mechanisms.

B. species clusters.

Natural hybrids between distantly related animal species are typically A. more fit than their parents B. sterile C. creating lots of new species D. reducing the number of species

B. sterile

About 80% of the alleles present in thoroughbred horses can be dated back to 31 known ancestors from the late eighteenth century. As a result, one would expect A. low rates of mutation B. many polymorphic alleles C little variation in physiology and behavior D. Hardy-Weinberg equilibrium

C little variation in physiology and behavior

In comparing artificial and natural selection, which of the following statements is true? A. Artificial selection is slower than natural selection. B. Artificial selection is reversible; natural selection is not. C. Artificial selection can produce maladaptive structures, natural selection cannot. D. Artificial selection cannot produce changes as large as changes produced by natural selection. E. In artificial selection, the magnitude of the selection pressure can be varied; in natural selection, it cannot.

C. Artificial selection can produce maladaptive structures, natural selection cannot.

Which of these conditions are always true of populations evolving due to natural selection? Condition 1: The population must vary in traits that are heritable. Condition 2: Some heritable traits must increase reproductive success. Condition 3: Individuals pass on all traits they acquire during their lifetime. A. Condition 1 only B. Condition 2 only C. Condition 1 and 2 D. Condition 1, 2, and 3

C. Condition 1 and 2

Evolution is sometimes said to violate the second law of thermodynamics. Which of the following statements best describes why evolution does NOT violate the second law? A. Evolution produces as many complex forms as it does less complex forms, balancing things out. B. Because evolution is a random process, it does not require an input of energy. C. Earth is not a closed system; it constantly receives an input of energy from the sun. D. The disorder generated by extinction balances the order created by evolution

C. Earth is not a closed system; it constantly receives an input of energy from the sun.

Evolution is sometimes said to violate the second law of thermodynamics. Which of the following statements best describes why this is true? A. Evolution produces as many complex forms as it does less complex forms, balancing things out. B. Because evolution is a random process, it does not require an input of energy. C. Earth is not a closed system; it constantly receives an input of energy from the sun. D. The disorder generated by extinction balances the order created by evolution

C. Earth is not a closed system; it constantly receives an input of energy from the sun.

HIV, human immunodeficiency virus, is the causative agent of AIDS. Which of the following statements is false? A. HIV mutates rapidly in infected individuals. B. HIV is amenable to phylogenetic analysis. C. HIV was transmitted to humans from a simian source just once. D. HIV has spread rapidly in humans worldwide.

C. HIV was transmitted to humans from a simian source just once.

Which of the following is a true statement concerning genetic variation? A. It is created by the direct action of natural selection. B. It arises in response to changes in the environment. C. It must be present in a population before natural selection can act upon the population. D. It tends to be reduced by the processes involved when diploid organisms produce gametes.

C. It must be present in a population before natural selection can act upon the population.

Why is the presence of wings not used to determine the phylogeny of mammals and birds? A. Not derived traits B. Not ancestral traits C. Not homologous traits D. Not all birds can fly

C. Not homologous traits

If all of the assumptions of the Hardy-Weinberg equilibrium were met, what would happen to the frequency of the recessive allele after many generations of mating? A. Increase B. Decrease C. Remain the same D. It depends on the starting frequencies

C. Remain the same

_______ selection occurs when the extremes of a population contribute relatively few offspring to the next generation as compared to average members of the original population A. Corrective B. Directional C. Stabilizing D. Disruptive E. Natural

C. Stabilizing

An earthquake decimates a ground-squirrel population. The surviving population happens to have broader stripes on average than the initial population. If broadness of stripes is genetically determined, what effect has the ground-squirrel population experienced during the earthquake? A. directional selection B. disruptive selection C. a genetic bottleneck D. gene flow

C. a genetic bottleneck

The phenomenon of fusion of two species is likely to occur when, after a period of geographic isolation, two populations meet again and A. their chromosomes are no longer homologous enough to permit meiosis. B. the hybrid zone is inhospitable to hybrid survival. C. an increasing number of viable, fertile hybrids is produced over the course of generations. D. a decreasing number of viable, fertile hybrids is produced over the course of generations.

C. an increasing number of viable, fertile hybrids is produced over the course of generations.

Plants, and their predecessors, green algae, do not share the property of A. containing chlorophylls a and b, and carotenoids. B. containing cellulose-rich cell walls. C. containing a system of roots and stems. D. containing starch as the primary food storage product. E. forming a cell plate during cytokinesis.

C. containing a system of roots and stems

Currently the only predators of Galápagos marine iguanas are Galápagos hawks. Iguana body size is not correlated with risk of hawk predation, although small iguanas can sprint faster than large iguanas. If predators (e.g., cats) that preferably catch and eat slower iguanas are introduced to the island, iguana body size is likely to _____ in the absence of other factors; the iguanas would then be under _____ selection. A. increase; directional B. increase; disruptive C. decrease; directional D. decrease; disruptive

C. decrease; directional

When selection acts to eliminate one extreme from an array of phenotypes it is called A. stabilizing selection B. disruptive selection C. directional selection D. artificial selection

C. directional selection

Suppose that females of a species of beetles prefer to mate with males that have relatively rare color patterns. This observation would be an illustration of A. genetic drift B. the founder effect C. frequency-dependent selection D. disruptive selection

C. frequency-dependent selection

A unique feature of angiosperms is A. roots B. seeds C. fruit D. pollen

C. fruit

Both ancestral birds and ancestral mammals shared a common ancestor that was terrestrial. Today, penguins (which are birds) and seals (which are mammals) have forelimbs adapted for swimming. What term best describes the relationship of the bones in the forelimbs of penguins and seals, and what term best describes the flippers of penguins and seals? A. homologous; homologous B. analogous; homologous C. homologous; analogous D. analogous; analogous

C. homologous; analogous

Which of the following sets of allele frequencies would produce the greatest proportion of heterozygotes? A. p = 0.9 q = 0.1 B. p = 0.7 q = 0.3 C. p = 0.5 q = 0.5 D. p = 0.2 q = 0.8 E. p = 0.05 q = 0.95

C. p = 0.5 q = 0.5

When species are kept separate by preventing the formation of hybrid zygotes, the mechanism that keeps the species separate is known as a(n) _____________ barrier. A. hybridization B. post-zygotic C. pre-zygotic D. adaptive E. differential

C. pre-zygotic

Sympatric refers to species which are A. hybridizing B. separating C. present in the same environment D. present in different environments

C. present in the same environment

Once species have formed, they keep their identity by A. developmental differences. B. genetic blocks. C. reinforcement. D. somatic mutations. E. structural modifications.

C. reinforcement.

The frequency of a particular allele within a population can be changed, over time, by A. genetic outflow. B. large population size. C. selection. D. inheritance of acquired characteristics. E. random mating.

C. selection

Derived character states shared by clade members are called A. ancestral traits. B. homoplasies. C. synapomorphies. D. plesiomorphies. E. symplesiomorphies.

C. synapomorphies.

In directional selection, over time A. the population that is strongly selected for is the mid-range. B. the most extreme outliers of a population are eliminated. C. the population is strongly selected for in one direction. D. the population is strongly selected for in two directions. E. a population increases its variation.

C. the population is strongly selected for in one direction.

Suppose 64% of a remote mountain village can taste phenylthiocarbamide (PTC) and must therefore have at least one copy of the dominant PTC taster allele. If this population conforms to Hardy-Weinberg expectations for this gene, what percentage of the population must be heterozygous for this trait? A. 16% B. 32% C. 40% D. 48% E. 60%

D. 48%

Features that increase the likelihood of survival and reproduction by an organism in a particular environment are called A. Genes. B. Fitness. C. Mutations. D. Adaptations.

D. Adaptations

The key point in Darwin's theory is that the ___________ imposes the conditions that determine the results of selection and thus the direction of selection. A. Parent B. Gene C. Individual D. Environment

D. Environment

The genetic contribution of an individual to succeeding generations, compared with that of other individuals in the population, is known as A. Variation. B. Microevolution. C. Macroevolution. D. Fitness. E. Adaptive makeup.

D. Fitness

The genetic contribution of an individual to succeeding generations, compared with that of other individuals in the population, is known as A. Variation. B. Microevolution. C. Macroevolution. D. Fitness.

D. Fitness.

Which of the following is thought to play a role in the adaptive radiation of Drosophila in Hawaii, Darwin's finches in the Galapagos, and cichlids in Lake Victoria. A. Presence of islands B. Tropical temperatures C. Tourists releasing pets D. Fragmented habitat

D. Fragmented habitat

Which of the following is thought to be the common ancestor of all land plants? A. Sponges B. Bacteria C. Ferns D. Green algae

D. Green algae

Natural selection is based on all of the following except A. Genetic variation exists within populations. B. The best-adapted individuals tend to leave the most offspring. C. Populations tend to produce more individuals than the environment can support. D. Individuals adapt to their environments and, thereby, evolve

D. Individuals adapt to their environments and, thereby, evolve

Vestigial structures are ____________. A. Structures found in different species that have similar functions B. Structure with different appearances and functions but have a common ancestor C. Examples of convergent evolution D. Non-functional structures left over from an organism's evolutionary past

D. Non-functional structures left over from an organism's evolutionary past

Within the life cycle of a pine, which of the following structures are haploid? A. Nucleus B. Tracheids C. Xylem D. Pollen grain

D. Pollen grain

Which of the following is not a cause of changes in the genetic structure of population? A. Mutation B. Gene flow C. Genetic drift D. Random mating E. Natural selection

D. Random mating

Which of the following often involves polyploidy? A. Extinction B. Allopatric speciation in animals C. Adaptive radiation D. Sympatric speciation in plants

D. Sympatric speciation in plants

A large volcanic eruption occurs and separates a valley with a species of red squirrels with a huge lava flow that the squirrels cannot cross, thus producing two isolated populations of squirrels. What change needs to occur for the two populations of squirrels to become separate species? A. The two squirrel populations must eat distinct species of plants. B. The fur color of the two squirrel populations must become distinct. C. The two squirrel populations select mates using the same sexual behavior. D. The two squirrel populations become reproductively isolated.

D. The two squirrel populations become reproductively isolated.

Different courtship rituals in different animal species is an example of A. mechanical isolation B. hybrid zones C. hybrid vigor D. behavioral isolation

D. behavioral isolation

As adaptions for flight, the wings of bats and the wings of birds are an example of A. shared derived traits. B. evolutionary reversal. C. monophyly. D. convergent evolution.

D. convergent evolution

Angiosperms are primarily characterized by all of the following except A. ovules are enclosed within other tissues at the time of pollination. B. a seed develops within a carpel. C. the ovary matures into the fruit. D. free water is required for pollination. E. they bear flowers which are modified stems bearing modified leaves.

D. free water is required for pollination.

A group of taxa that includes a common ancestor, all descendants of that ancestor, and no other organisms is considered to be A. paraphyletic. B. polyphyletic. C. convergent. D. monophyletic.

D. monophyletic.

Compared with Hardy-Weinberg predictions, populations that have practiced assortative mating have A. fewer homozygotes. B. less natural selection. C. more heterozygotes. D. more homozygotes. E. more mutations

D. more homozygotes.

In order for natural selection to occur within a population, certain conditions must be met. One such condition is A. phenotypic differences resulting from environmental conditions. B. frequent mutations that are inherited. C. low rates of immigration. D. phenotypic variations that are genetic. E. heterozygosity must be very low.

D. phenotypic variations that are genetic.

The production of new species through hybridization is especially important in A. finches. B. fruit flies. C. humans. D. plants.

D. plants

All tracheophyte plants are characterized by all of the following except A. specialized conducting systems. B. waxy cuticle. C. stomata. D. seeds.

D. seeds

The diversity of cichlids in Lake Victoria appears to be due to A. the large number of species originally brought there from other lakes by flooding B. glaciation dividing the lake into many smaller lakes C. the large number of isolated islands in the lake D. the key innovation of a second set of jaws, allowing specialization on many different food sources

D. the key innovation of a second set of jaws, allowing specialization on many different food sources

If 81% of a population is homozygous recessive for a given trait, what is the predicted frequency of homozygous dominant? A. 0.9 B. 0.36 C. 0.18 D. 0.1 E. 0.01

E. 0.01

In a population at Hardy-Weinberg equilibrium, the frequency of the a allele is 0.60. What is the frequency of individuals heterozygous for the A gene? A. 0.16 B. 0.24 C. 0.36 D. 0.40 E. 0.48

E. 0.48

Which one of the following could not apply to a post-zygotic isolating mechanism? A. Hybrids are sterile. B. Hybrids develop abnormally. C. Hybrids fail to become established in nature. D. Hybrids are selected against. E. Hybrids cannot be formed.

E. Hybrids cannot be formed.

Which of the following would be a shared derived trait that would be used to separate a monkey and a rabbit from a lizard, frog, and shark? A. Lungs B. Tail C. Heart D. Teeth E. Mammary glands F. Hair

E. Mammary glands F. Hair

Which of the following is not required for evolution by natural selection? A. Time B. Variation C. Genetic inheritance D. Selection E. Sexual reproduction

E. Sexual reproduction

The gene pool includes all of the A. fitness within a population. B. individuals within a population. C. mutations within a population. D. adaptations within a population. E. alleles of genes within a population.

E. alleles of genes within a population.

Sometimes a restriction in genetic variability is imposed on populations by natural catastrophes such as flooding, earthquake, etc. The surviving individuals reflect only a small, random genetic sample of the population affected. This process is termed A. mutation. B. migration. C. genetic drift. D. assortative mating. E. bottleneck effect.

E. bottleneck effect.

The Hardy-Weinberg equilibrium conditions for populations of organisms result in A. polymorphic alleles B. assortative mating C. natural selection D. maintenance of recessive alleles in the gene pool E. no evolutionary changes

E. no evolutionary change

Character states shared by the ancestor or outgroup of a clade are called A. derived traits. B. homoplasies. C. synapomorphies. D. plesiomorphies. E. symplesiomorphies.

E. symplesiomorphies.