- Darwin argues that the process of domestication demonstrates how humans can influence the evolution of species. What specific example does he use to highlight this concept?
- A: The English Carrier Pigeon
- B: The Fantail Pigeon
- C: The Domestic Duck
- D: The Water-ouzel
Correct Answer: A Correct Answer Explanation: Darwin uses the English Carrier Pigeon’s abnormally long beak, a trait selected for by breeders, to illustrate how humans can intentionally alter the characteristics of a species.
- Darwin suggests that in nature, certain species may become “extinct” over time. Which of these factors does he identify as a primary cause of extinction?
- A: The introduction of invasive species
- B: The impact of disease outbreaks
- C: The struggle for existence and competition for resources
- D: The changing climate and environmental shifts
Correct Answer: C Correct Answer Explanation: Darwin asserts that the “struggle for existence” between organisms for limited resources, which leads to a “survival of the fittest,” is a key driver of extinction.
- Darwin explores the phenomenon of “sports,” which are sudden and dramatic variations within a species. Where are these sports more commonly observed?
- A: In wild populations
- B: In domesticated animals and plants
- C: In isolated geographic regions
- D: In environments with extreme climatic conditions
Correct Answer: B Correct Answer Explanation: Darwin notes that “sports” are more frequent in domesticated species, likely due to the influence of the parent’s environment and artificial selection.
- According to Darwin, which of these groups tend to exhibit more variation?
- A: Species with restricted geographical ranges
- B: Species belonging to larger genera
- C: Species that are recently evolved
- D: Species with a high degree of genetic diversity
Correct Answer: B Correct Answer Explanation: Darwin observes that species within larger genera (containing multiple species) tend to display greater variability, reflecting their longer history of diversification and adaptation.
- Darwin’s theory of evolution by natural selection emphasizes the importance of “variations” within a species. Which of these factors does he identify as the source of these variations?
- A: Environmental influences
- B: Genetic mutations
- C: The struggle for existence
- D: The inheritance of acquired characteristics
Correct Answer: B Correct Answer Explanation: Though Darwin didn’t fully understand the mechanisms of inheritance, he recognized that variations arise from differences in individuals, which is now known to be caused by genetic mutations.
- Darwin argues that natural selection can act on different stages of an organism’s life cycle. What specific example does he use to illustrate this concept?
- A: The evolution of flight in birds
- B: The development of horns in male animals
- C: The adaptations of the Water-ouzel
- D: The survival of larvae in insects
Correct Answer: D Correct Answer Explanation: Darwin suggests that adaptations that benefit the larval stage of insects, for instance, can ultimately affect the adult form through the “correlation of growth” between different stages.
- Darwin identifies a secondary form of selection called “sexual selection.” What does this form of selection primarily focus on?
- A: The survival of individuals in harsh environments
- B: The acquisition of resources and food
- C: The ability to attract mates
- D: The development of beneficial adaptations
Correct Answer: C Correct Answer Explanation: Darwin defines sexual selection as the process where individuals with traits that enhance their chances of attracting mates are more likely to reproduce, leading to the evolution of features like elaborate plumage or horns.
- Darwin believes that the occasional interbreeding between individuals of different varieties or species is crucial for maintaining the vigor and fertility of a population. What term does he use to describe this phenomenon?
- A: Hybridization
- B: Polymorphism
- C: Incipient speciation
- D: Natural selection
Correct Answer: A Correct Answer Explanation: Darwin suggests that hybridization, the interbreeding of different varieties or species, is a common process in nature and contributes to genetic diversity and population health.
- Darwin argues that isolation plays a critical role in the process of evolution. What specific effect does isolation have on populations?
- A: It promotes gene flow and genetic mixing
- B: It increases competition for resources
- C: It allows for the development of distinct forms
- D: It reduces the frequency of mutations
Correct Answer: C Correct Answer Explanation: Darwin emphasizes that isolated populations, limited in their ability to interbreed with other groups, are more likely to develop unique adaptations and eventually evolve into distinct species.
- In his book, Darwin presents a multitude of facts and observations to support his theory of evolution by natural selection. Which of these examples does he use to demonstrate the influence of habit on the variation of animals?
- A: The long beak of the English Carrier pigeon
- B: The wingless beetles of Madeira
- C: The bones of the domestic duck
- D: The adaptation of the Water-ouzel
Correct Answer: C Correct Answer Explanation: Darwin observes that the domestic duck, flying less and walking more than its wild ancestor, exhibits changes in bone structure, highlighting how habits can influence physical adaptations.
- Darwin provides numerous examples of natural selection in action, illustrating the power of this evolutionary force. Which of these examples does he use to showcase the struggle for existence among organisms of the same species?
- A: The competition between native and introduced plants
- B: The relationship between humble-bees and red clover
- C: The destruction of native weeds by slugs and insects
- D: The limited number of Scotch fir trees in enclosed areas
Correct Answer: C Correct Answer Explanation: Darwin uses the observation that a significant proportion of native weed seedlings are destroyed by slugs and insects, demonstrating the intense competition for survival within a single species.
- Darwin introduces the concept of “analogical” or “adaptive characters.” What distinguishes these characters from other types of features?
- A: They are inherited from a common ancestor
- B: They are similar in appearance and function but evolved independently
- C: They are remnants of structures that were once functional
- D: They are influenced by the environment
Correct Answer: B Correct Answer Explanation: Darwin describes analogical characters as features that share a similar appearance and purpose but have evolved independently in different lineages, demonstrating the convergence of form under similar environmental pressures.
- Darwin uses the example of “humble-bees” and “red clover” to illustrate a specific principle. What principle is demonstrated by this relationship?
- A: The interdependence of organisms within an ecosystem
- B: The impact of natural selection on populations
- C: The importance of variation within a species
- D: The influence of isolation on evolution
Correct Answer: A Correct Answer Explanation: Darwin highlights the interdependence of humble-bees and red clover, showing that the survival of one species depends on the presence of the other, illustrating the complex web of relationships within ecosystems.
- Darwin provides evidence for the slow and gradual nature of evolutionary change. What specific example does he use to demonstrate the potential for gradual transformation over long periods?
- A: The wingless beetles of Madeira
- B: The fantail pigeon’s large number of tail feathers
- C: The evolution of flight in bats
- D: The adaptation of flying squirrels
Correct Answer: D Correct Answer Explanation: Darwin observes the gradual transition from squirrels with slightly flattened tails to those with fully developed flank membranes, suggesting the potential for slow and incremental changes that ultimately lead to significant adaptations.
- Darwin discusses the concept of “rudimentary organs” – organs that are reduced in size and function. What does the presence of these organs suggest?
- A: That these structures were once functional in the ancestor
- B: That they are still undergoing active evolution
- C: That they are essential for survival
- D: That they have arisen through recent genetic mutations
Correct Answer: A Correct Answer Explanation: Darwin argues that rudimentary organs, like the appendix in humans, represent remnants of structures that were once functional in ancestral organisms, providing evidence for evolutionary history.
- Darwin emphasizes the role of “climate” in determining the average number of individuals within a species. How does climate indirectly affect population size?
- A: By directly influencing genetic mutations
- B: By altering the availability of food resources
- C: By promoting interbreeding between species
- D: By creating isolation and reducing gene flow
Correct Answer: B Correct Answer Explanation: Darwin suggests that climate, through its effects on food availability and the distribution of other organisms, indirectly influences population size by affecting the survival and reproduction of individuals.
- Darwin uses the example of the “Water-ouzel” to demonstrate a specific concept. What concept is illustrated by this bird?
- A: The convergence of form in unrelated species
- B: The rapid pace of evolutionary change
- C: The influence of habits on adaptation
- D: The importance of isolation in speciation
Correct Answer: C Correct Answer Explanation: Darwin highlights the Water-ouzel, a diving bird within a terrestrial family, suggesting that habits can change without a corresponding change in structure, emphasizing the influence of behavior on adaptation.
- Darwin explores the idea of “natural selection” acting on variations within a species, regardless of their magnitude. What does this imply about the process of evolution?
- A: That small changes can accumulate over time
- B: That only major mutations can drive evolution
- C: That all variations are equally beneficial
- D: That natural selection is a random process
Correct Answer: A Correct Answer Explanation: Darwin’s central point is that even seemingly insignificant variations, if advantageous, can contribute to the gradual accumulation of changes that lead to the evolution of new species.
- Darwin argues that the fossil record provides evidence for the gradual transformation of life over time. What specific example does he use to support this claim?
- A: The existence of rudimentary organs
- B: The presence of analogical characters
- C: The distribution of species across continents
- D: The presence of different layers of fossilized plants and animals
Correct Answer: D Correct Answer Explanation: Darwin observes that fossils found in different geological layers reflect changes in life forms over vast periods, providing evidence for the gradual transformation of species over time.
- Darwin explores the concept of “introduced species” – species that are intentionally or accidentally brought into new environments. What does the success of these introduced species often indicate?
- A: That native species are perfectly adapted to their environment
- B: That introduced species are inherently superior
- C: That the native environment is unstable
- D: That native species are vulnerable to competition
Correct Answer: D Correct Answer Explanation: Darwin notes that the success of introduced species often suggests that native species are not perfectly adapted to their environment and may be susceptible to competition from new arrivals.
- Darwin uses the term “variety” to describe a form within a species that differs from the typical form. What distinguishes a variety from a separate species?
- A: Varieties are genetically identical to the typical form
- B: Varieties cannot reproduce with the typical form
- C: Varieties are always isolated geographically
- D: Varieties can interbreed with the typical form
Correct Answer: D Correct Answer Explanation: Darwin emphasizes that varieties, while differing from the typical form of a species, can still interbreed and produce fertile offspring, distinguishing them from distinct species.
- Darwin examines the relationship between “species” and “genera.” What does he observe about the variation within species belonging to larger genera?
- A: They tend to vary less than species in smaller genera
- B: They tend to vary more than species in smaller genera
- C: They are typically more isolated geographically
- D: They are more susceptible to extinction
Correct Answer: B Correct Answer Explanation: Darwin suggests that species within larger genera, due to their longer history of diversification, tend to exhibit greater variation, reflecting their greater evolutionary flexibility.
- Darwin’s theory of evolution emphasizes the importance of “inheritance.” Which of these factors does he identify as the primary mechanism of inheritance?
- A: The blending of parental characteristics
- B: The transmission of acquired traits
- C: The influence of the environment
- D: The action of natural selection
Correct Answer: A Correct Answer Explanation: While Darwin didn’t fully understand the mechanisms of inheritance, he proposed that offspring inherit a blend of characteristics from their parents, a concept that was later replaced by the understanding of genes and Mendelian inheritance.
- Darwin discusses the impact of “confinement” on the reproductive systems of animals. What specific effect does confinement have on breeding?
- A: It increases the rate of genetic mutations
- B: It enhances the ability of animals to adapt
- C: It often hinders the ability of animals to breed freely
- D: It promotes hybridization between species
Correct Answer: C Correct Answer Explanation: Darwin observes that many animals fail to breed freely when kept in captivity, suggesting that their reproductive systems are sensitive to changes in their environment and the influence of confinement.
- Darwin uses the example of “flying squirrels” to illustrate a specific principle. What principle is demonstrated by this example?
- A: The importance of isolation in evolution
- B: The gradual nature of evolutionary change
- C: The convergence of form in unrelated species
- D: The impact of sexual selection on adaptation
Correct Answer: B Correct Answer Explanation: Darwin examines the gradual transition from squirrels with slightly flattened tails to those with fully developed flank membranes, showcasing the potential for slow and incremental changes that ultimately lead to significant adaptations.
- Darwin argues that the process of “natural selection” is constantly occurring in nature. What does this imply about the evolution of species?
- A: That species are static and unchanging
- B: That species are constantly evolving and adapting
- C: That evolution is a linear process
- D: That natural selection is a random process
Correct Answer: B Correct Answer Explanation: Darwin asserts that natural selection is an ongoing process that constantly shapes the characteristics of species, leading to continuous adaptation and evolution.
- Darwin observes that species very closely related to other species often have restricted ranges. What does this suggest about these closely related species?
- A: They are likely to be ancient lineages
- B: They are likely to be recently evolved forms
- C: They are highly adapted to their environments
- D: They are vulnerable to extinction
Correct Answer: B Correct Answer Explanation: Darwin suggests that closely related species with restricted ranges are likely to be recently evolved forms that haven’t had sufficient time to spread widely, demonstrating the ongoing process of speciation.
- Darwin uses the example of “Galeopithecus,” a gliding mammal, to illustrate a specific concept. What concept is illustrated by this example?
- A: The importance of isolation in speciation
- B: The existence of intermediate forms in evolution
- C: The impact of climate change on adaptation
- D: The role of sexual selection in evolution
Correct Answer: B Correct Answer Explanation: Darwin examines the Galeopithecus, a gliding mammal that was once mistakenly classified as a bat, suggesting that intermediate forms might have existed in the past, connecting it to other lemurs. This example highlights the idea of transitional forms in the evolutionary process.
- Darwin provides several examples of how the environment can influence the evolution of species. Which of these examples demonstrates the influence of the environment on the development of physical traits?
- A: The evolution of wingless beetles on Madeira
- B: The adaptation of the Water-ouzel to aquatic life
- C: The long beak of the English Carrier pigeon
- D: The fantail pigeon’s large number of tail feathers
Correct Answer: A Correct Answer Explanation: Darwin observes that a significant proportion of beetles on Madeira have lost their wings, likely due to the influence of the island’s environment, demonstrating how the environment can shape physical adaptations.
- Darwin uses the concept of “polymorphism” to describe a species exhibiting a high degree of variation within its population. What does this concept suggest about the evolution of species?
- A: That variation is essential for adaptation
- B: That all variation is beneficial
- C: That evolution is a linear process
- D: That natural selection is random
Correct Answer: A Correct Answer Explanation: Darwin’s concept of polymorphism emphasizes that variation within a species is essential for adaptation, as it provides the raw material for natural selection to act upon, leading to the evolution of new traits.
- Darwin discusses the concept of “incipient species” – varieties that are in the process of becoming distinct species. What distinguishes incipient species from established species?
- A: Incipient species are genetically identical to the parent species
- B: Incipient species cannot reproduce with the parent species
- C: Incipient species are geographically isolated
- D: Incipient species are only partially isolated
Correct Answer: D Correct Answer Explanation: Darwin defines incipient species as varieties that are in the process of diverging from the parent species, often due to partial isolation, and are still capable of interbreeding but may be developing distinct traits.
- Darwin provides numerous examples of how species have adapted to their specific environments. Which of these examples demonstrates the adaptation of a species to a specific type of food source?
- A: The wingless beetles of Madeira
- B: The fantail pigeon’s large number of tail feathers
- C: The adaptation of the Water-ouzel to aquatic life
- D: The relationship between humble-bees and red clover
Correct Answer: D Correct Answer Explanation: Darwin highlights the interdependence of humble-bees and red clover, showcasing how the humble-bee’s ability to reach the nectar of red clover has evolved as an adaptation to a specific food source.
- Darwin argues that the “struggle for existence” is a fundamental principle that drives evolution. What is the primary consequence of this struggle?
- A: The extinction of all species
- B: The survival of the fittest individuals
- C: The creation of new species
- D: The increasing complexity of organisms
Correct Answer: B Correct Answer Explanation: Darwin asserts that the struggle for existence, where organisms compete for limited resources, leads to the survival of individuals with advantageous traits, promoting the “survival of the fittest.”
- Darwin uses the example of “woodpeckers” and “misseltoe” to illustrate a specific concept. What concept is demonstrated by this relationship?
- A: The interdependence of organisms within an ecosystem
- B: The impact of natural selection on populations
- C: The importance of variation within a species
- D: The influence of isolation on evolution
Correct Answer: A Correct Answer Explanation: Darwin highlights the complex adaptations of woodpeckers and misseltoe, showing how the woodpecker’s beak and feet are adapted for catching insects under bark, while the misseltoe depends on specific trees and birds for survival, illustrating the interdependence of organisms within an ecosystem.
- Darwin discusses the concept of “homologous organs” – organs in different species that have a similar underlying structure. What does the presence of homologous organs suggest?
- A: That these structures evolved independently
- B: That they are adaptations to similar environments
- C: That they are remnants of ancestral structures
- D: That they are influenced by the environment
Correct Answer: C Correct Answer Explanation: Darwin argues that homologous organs, like the limbs of humans, bats, and whales, reflect their shared ancestry, demonstrating that these structures have been modified over time from a common ancestral form.
- Darwin provides evidence for the interconnectedness of organisms within an ecosystem. Which of these examples illustrates this interconnectedness?
- A: The adaptation of the Water-ouzel to aquatic life
- B: The competition between native and introduced plants
- C: The relationship between humble-bees and red clover
- D: The wingless beetles of Madeira
Correct Answer: C Correct Answer Explanation: Darwin highlights the dependence of red clover on humble-bees for pollination, demonstrating that the survival of one species is linked to the presence of the other, illustrating the interconnectedness of organisms within an ecosystem.
- Darwin observes that the number of eggs or seeds produced by a species is not a direct indicator of its abundance. What does this observation suggest about the survival of offspring?
- A: That all offspring have an equal chance of survival
- B: That only the strongest offspring survive
- C: That many offspring perish at an early stage
- D: That the number of offspring is irrelevant to survival
Correct Answer: C Correct Answer Explanation: Darwin suggests that a large number of offspring merely compensates for high mortality rates at an early stage of life, indicating that survival is a competitive process where many offspring do not reach adulthood.
- Darwin examines the impact of “introduced species” on native ecosystems. What is the most common outcome of the introduction of new species?
- A: Increased biodiversity and stability
- B: Improved adaptation of native species
- C: Outcompetition of native species
- D: A harmonious coexistence
Correct Answer: C Correct Answer Explanation: Darwin notes that introduced species often outcompete native species for resources, disrupting the balance of the ecosystem and potentially leading to the decline or extinction of native populations.
- Darwin discusses the concept of “correlation of growth” – the influence of one part of the body on the development of other parts. What example does he use to illustrate this concept?
- A: The long beak of the English Carrier pigeon
- B: The wingless beetles of Madeira
- C: The adaptation of the Water-ouzel to aquatic life
- D: The cats with blue eyes and deafness
Correct Answer: D Correct Answer Explanation: Darwin observes that cats with blue eyes are invariably deaf, highlighting the existence of a correlation between these seemingly unrelated traits, demonstrating that changes in one part of the body can affect the development of other parts.
- Darwin uses the term “mongrel” to describe the offspring of two different varieties of the same species. What is the equivalent term for the offspring of two different species?
- A: Incipient species
- B: Variety
- C: Hybrid
- D: Polymorphic
Correct Answer: C Correct Answer Explanation: Darwin distinguishes between “mongrels,” the offspring of different varieties within the same species, and “hybrids,” the offspring of two distinct species.
- Darwin argues that the “struggle for existence” is most severe between individuals of the same species. What is the primary reason for this intense competition?
- A: Differences in genetic makeup
- B: Competition for the same resources
- C: Territorial disputes
- D: Sexual selection
Correct Answer: B Correct Answer Explanation: Darwin suggests that the most intense competition occurs between individuals of the same species because they have similar requirements for resources, leading to direct competition for food, shelter, and other necessities.
- Darwin uses the example of “Scotch fir trees” to illustrate a specific principle. What principle is demonstrated by this example?
- A: The importance of isolation in evolution
- B: The gradual nature of evolutionary change
- C: The influence of the environment on adaptation
- D: The interconnectedness of organisms within an ecosystem
Correct Answer: D Correct Answer Explanation: Darwin observes that the presence or absence of Scotch fir trees in an area can be determined by the grazing patterns of cattle, highlighting the complex and indirect relationships between species within an ecosystem.
- Darwin provides evidence for the concept of “natural selection” acting on variations, no matter how slight. What does this imply about the importance of small differences?
- A: That small differences are insignificant in the long term
- B: That small differences can accumulate and lead to major changes
- C: That only large mutations drive evolution
- D: That all variations are equally beneficial
Correct Answer: B Correct Answer Explanation: Darwin’s central point is that even seemingly insignificant variations, if advantageous, can contribute to the gradual accumulation of changes that lead to the evolution of new species.
- Darwin discusses the concept of “extinction” as an inevitable consequence of evolution. What is the primary reason for extinction?
- A: The lack of genetic variation within a species
- B: The inability to adapt to changing environments
- C: The introduction of new species
- D: The impact of disease outbreaks
Correct Answer: B Correct Answer Explanation: Darwin argues that species that are unable to adapt to changing environments, either through competition, climate change, or other factors, are likely to be outcompeted and eventually become extinct.
- Darwin explores the impact of “climate” on the distribution and abundance of species. What specific effect does climate have on populations?
- A: It directly influences the rate of genetic mutations
- B: It promotes interbreeding between species
- C: It reduces food availability and favors competitors
- D: It creates isolation and reduces gene flow
Correct Answer: C Correct Answer Explanation: Darwin suggests that climate indirectly affects population size by influencing the availability of food resources and favoring the spread of competitors, impacting the survival and reproduction of individuals.
- Darwin provides several examples of how the environment can influence the evolution of species. Which of these examples demonstrates the influence of the environment on the development of behavioral adaptations?
- A: The wingless beetles of Madeira
- B: The adaptation of the Water-ouzel to aquatic life
- C: The long beak of the English Carrier pigeon
- D: The fantail pigeon’s large number of tail feathers
Correct Answer: B Correct Answer Explanation: Darwin observes the Water-ouzel, a diving bird within a terrestrial family, suggesting that habits can change without a corresponding change in structure, emphasizing the influence of behavior on adaptation.
- Darwin discusses the concept of “analogical” or “adaptive characters.” What distinguishes these characters from other types of features?
- A: They are inherited from a common ancestor
- B: They are similar in appearance and function but evolved independently
- C: They are remnants of structures that were once functional
- D: They are influenced by the environment
Correct Answer: B Correct Answer Explanation: Darwin describes analogical characters as features that share a similar appearance and purpose but have evolved independently in different lineages, demonstrating the convergence of form under similar environmental pressures.
- Darwin uses the example of “humble-bees” and “red clover” to illustrate a specific principle. What principle is demonstrated by this relationship?
- A: The interdependence of organisms within an ecosystem
- B: The impact of natural selection on populations
- C: The importance of variation within a species
- D: The influence of isolation on evolution
Correct Answer: A Correct Answer Explanation: Darwin highlights the interdependence of humble-bees and red clover, showing that the survival of one species depends on the presence of the other, illustrating the complex web of relationships within ecosystems.
- Darwin provides evidence for the slow and gradual nature of evolutionary change. What specific example does he use to demonstrate the potential for gradual transformation over long periods?
- A: The wingless beetles of Madeira
- B: The fantail pigeon’s large number of tail feathers
- C: The evolution of flight in bats
- D: The adaptation of flying squirrels
Correct Answer: D Correct Answer Explanation: Darwin observes the gradual transition from squirrels with slightly flattened tails to those with fully developed flank membranes, suggesting the potential for slow and incremental changes that ultimately lead to significant adaptations.
- Darwin argues that the fossil record provides evidence for the gradual transformation of life over time. What specific example does he use to support this claim?
- A: The existence of rudimentary organs
- B: The presence of analogical characters
- C: The distribution of species across continents
- D: The presence of different layers of fossilized plants and animals
Correct Answer: D Correct Answer Explanation: Darwin observes that fossils found in different geological layers reflect changes in life forms over vast periods, providing evidence for the gradual transformation of species over time.
- Darwin explores the concept of “rudimentary organs” – organs that are reduced in size and function. What does the presence of these organs suggest?
- A: That these structures were once functional in the ancestor
- B: That they are still undergoing active evolution
- C: That they are essential for survival
- D: That they have arisen through recent genetic mutations
Correct Answer: A Correct Answer Explanation: Darwin argues that rudimentary organs, like the appendix in humans, represent remnants of structures that were once functional in ancestral organisms, providing evidence for evolutionary history.
- Darwin emphasizes the role of “climate” in determining the average number of individuals within a species. How does climate indirectly affect population size?
- A: By directly influencing genetic mutations
- B: By altering the availability of food resources
- C: By promoting interbreeding between species
- D: By creating isolation and reducing gene flow
Correct Answer: B Correct Answer Explanation: Darwin suggests that climate, through its effects on food availability and the distribution of other organisms, indirectly influences population size by affecting the survival and reproduction of individuals.
- Darwin uses the example of the “Water-ouzel” to demonstrate a specific concept. What concept is illustrated by this bird?
- A: The convergence of form in unrelated species
- B: The rapid pace of evolutionary change
- C: The influence of habits on adaptation
- D: The importance of isolation in speciation
Correct Answer: C Correct Answer Explanation: Darwin highlights the Water-ouzel, a diving bird within a terrestrial family, suggesting that habits can change without a corresponding change in structure, emphasizing the influence of behavior on adaptation.
- Darwin argues that the process of “natural selection” is constantly occurring in nature. What does this imply about the evolution of species?
- A: That species are static and unchanging
- B: That species are constantly evolving and adapting
- C: That evolution is a linear process
- D: That natural selection is a random process
Correct Answer: B Correct Answer Explanation: Darwin asserts that natural selection is an ongoing process that constantly shapes the characteristics of species, leading to continuous adaptation and evolution.
- Darwin observes that species very closely related to other species often have restricted ranges. What does this suggest about these closely related species?
- A: They are likely to be ancient lineages
- B: They are likely to be recently evolved forms
- C: They are highly adapted to their environments
- D: They are vulnerable to extinction
Correct Answer: B Correct Answer Explanation: Darwin suggests that closely related species with restricted ranges are likely to be recently evolved forms that haven’t had sufficient time to spread widely, demonstrating the ongoing process of speciation.
- Darwin uses the example of “Galeopithecus,” a gliding mammal, to illustrate a specific concept. What concept is illustrated by this example?
- A: The importance of isolation in speciation
- B: The existence of intermediate forms in evolution
- C: The impact of climate change on adaptation
- D: The role of sexual selection in evolution
Correct Answer: B Correct Answer Explanation: Darwin examines the Galeopithecus, a gliding mammal that was once mistakenly classified as a bat, suggesting that intermediate forms might have existed in the past, connecting it to other lemurs. This example highlights the idea of transitional forms in the evolutionary process.
- Darwin provides several examples of how the environment can influence the evolution of species. Which of these examples demonstrates the influence of the environment on the development of physical traits?
- A: The evolution of wingless beetles on Madeira
- B: The adaptation of the Water-ouzel to aquatic life
- C: The long beak of the English Carrier pigeon
- D: The fantail pigeon’s large number of tail feathers
Correct Answer: A Correct Answer Explanation: Darwin observes that a significant proportion of beetles on Madeira have lost their wings, likely due to the influence of the island’s environment, demonstrating how the environment can shape physical adaptations.
- Darwin uses the term “variety” to describe a form within a species that differs from the typical form. What distinguishes a variety from a separate species?
- A: Varieties are genetically identical to the typical form
- B: Varieties cannot reproduce with the typical form
- C: Varieties are always isolated geographically
- D: Varieties can interbreed with the typical form
Correct Answer: D Correct Answer Explanation: Darwin emphasizes that varieties, while differing from the typical form of a species, can still interbreed and produce fertile offspring, distinguishing them from distinct species.
- Darwin examines the relationship between “species” and “genera.” What does he observe about the variation within species belonging to larger genera?
- A: They tend to vary less than species in smaller genera
- B: They tend to vary more than species in smaller genera
- C: They are typically more isolated geographically
- D: They are more susceptible to extinction
Correct Answer: B Correct Answer Explanation: Darwin suggests that species within larger genera, due to their longer history of diversification, tend to exhibit greater variation, reflecting their greater evolutionary flexibility.
- Darwin’s theory of evolution emphasizes the importance of “inheritance.” Which of these factors does he identify as the primary mechanism of inheritance?
- A: The blending of parental characteristics
- B: The transmission of acquired traits
- C: The influence of the environment
- D: The action of natural selection
Correct Answer: A Correct Answer Explanation: While Darwin didn’t fully understand the mechanisms of inheritance, he proposed that offspring inherit a blend of characteristics from their parents, a concept that was later replaced by the understanding of genes and Mendelian inheritance.