1. What is a fundamental niche?
a) The range of environmental conditions a species can theoretically survive in.
b) The actual habitat where a species lives.
c) The area a species occupies due to competition with other species.
d) The niche a species occupies without competition.
Answer: a) The range of environmental conditions a species can theoretically survive in.
Explanation: The fundamental niche refers to the full potential range of environmental conditions (abiotic and biotic) where a species can live and reproduce without the influence of competitors or predators.
2. What is a realized niche?
a) The role a species plays in the ecosystem under ideal conditions.
b) The actual space where a species lives and thrives, affected by competition and predation.
c) The complete range of abiotic factors a species can tolerate.
d) The theoretical conditions under which a species can survive.
Answer: b) The actual space where a species lives and thrives, affected by competition and predation.
Explanation: The realized niche is the subset of the fundamental niche that a species actually occupies in nature, constrained by biotic factors like competition, predation, and other interactions.
3. Which of the following best describes the relationship between fundamental and realized niches?
a) The fundamental niche is always larger than the realized niche.
b) The realized niche is always larger than the fundamental niche.
c) Both niches are always the same size.
d) Fundamental and realized niches are unrelated.
Answer: a) The fundamental niche is always larger than the realized niche.
Explanation: Due to biotic factors such as competition, the realized niche is often smaller than the fundamental niche, as some potential habitats are not accessible in nature.
4. Which factor can restrict a species to its realized niche?
a) Abiotic factors like temperature.
b) Predation and competition.
c) Available resources.
d) Both b and c.
Answer: d) Both b and c.
Explanation: Predation, competition, and the availability of resources all restrict a species to its realized niche by limiting where and how it can live in an ecosystem.
5. What is an example of a species occupying its fundamental niche?
a) A species living in a habitat with no predators.
b) A species living in a habitat with high competition from similar species.
c) A species in an environment where it faces extreme weather conditions.
d) A species that avoids its natural predators.
Answer: a) A species living in a habitat with no predators.
Explanation: When a species occupies its fundamental niche, it is in a situation where there are no biotic limitations like predators or competitors.
6. How do competitive interactions affect the realized niche?
a) They expand the realized niche.
b) They have no effect on the realized niche.
c) They constrain the realized niche, limiting available resources.
d) They make the fundamental niche irrelevant.
Answer: c) They constrain the realized niche, limiting available resources.
Explanation: Competitive interactions reduce the available resources in the realized niche, causing a species to occupy only a portion of its fundamental niche.
7. In which situation would a species most likely occupy its fundamental niche?
a) In an ecosystem with a high density of predators.
b) In an ecosystem with abundant resources and no competitors.
c) In an ecosystem with high disease prevalence.
d) In an ecosystem with a lot of human disturbances.
Answer: b) In an ecosystem with abundant resources and no competitors.
Explanation: A species will occupy its fundamental niche most likely when there are no limiting factors such as predators, competitors, or scarce resources.
8. What might cause a species’ realized niche to be smaller than its fundamental niche?
a) Adaptation to environmental changes.
b) Genetic mutations within the species.
c) The presence of competition and predation.
d) The species’ ability to overcome environmental stress.
Answer: c) The presence of competition and predation.
Explanation: Competitive exclusion and predation can reduce the portion of the environment in which a species can survive, leading to a realized niche that is smaller than the fundamental niche.
9. What is one potential consequence of niche overlap between two species?
a) Increased availability of resources for both species.
b) Reduced competition and predation.
c) Competitive exclusion of one species.
d) No effect on either species.
Answer: c) Competitive exclusion of one species.
Explanation: When two species have overlapping niches, one may outcompete the other for resources, resulting in the exclusion of the weaker species from that niche.
10. Which of the following represents a condition that could alter a species’ realized niche?
a) Climate change.
b) The introduction of a new predator.
c) Evolutionary adaptations to local conditions.
d) All of the above.
Answer: d) All of the above.
Explanation: Climate change, new predators, and evolutionary adaptations can all affect the realized niche by altering the conditions under which a species can thrive.
11. What term refers to the competitive exclusion of one species when two species occupy the same niche?
a) Resource partitioning.
b) Ecological specialization.
c) Niche differentiation.
d) Competitive exclusion principle.
Answer: d) Competitive exclusion principle.
Explanation: The competitive exclusion principle states that two species cannot occupy the same niche indefinitely if resources are limited, leading to the exclusion of one species.
12. Which concept is used to explain how two species can coexist despite sharing a similar niche?
a) Niche overlap.
b) Resource partitioning.
c) Mutualism.
d) Competitive exclusion.
Answer: b) Resource partitioning.
Explanation: Resource partitioning occurs when species divide resources to reduce competition, allowing them to coexist despite overlapping niches.
13. In which scenario would the fundamental niche of a species be larger than its realized niche?
a) When the species is experiencing environmental stress.
b) When the species faces many predators and competitors.
c) When the species is at the top of the food chain.
d) When the species adapts to a specific environment.
Answer: b) When the species faces many predators and competitors.
Explanation: A species’ realized niche is constrained by the presence of predators and competitors, making its realized niche smaller than its fundamental niche.
14. What is the primary factor that limits a species to its realized niche?
a) The species’ behavior.
b) The available habitat.
c) The presence of competitors, predators, and diseases.
d) The species’ evolutionary history.
Answer: c) The presence of competitors, predators, and diseases.
Explanation: The realized niche is primarily limited by biotic factors such as competition, predation, and the presence of diseases.
15. Which of the following would be considered a biotic factor in determining a species’ niche?
a) Temperature.
b) Soil pH.
c) Availability of prey.
d) Water availability.
Answer: c) Availability of prey.
Explanation: Biotic factors are living components, and the availability of prey is a biotic factor that can influence the realized niche of a predator.
16. A species of bird has access to a wide range of habitats but only occupies specific areas due to the presence of strong competitors. This is an example of:
a) Resource partitioning.
b) A realized niche.
c) A fundamental niche.
d) Competitive exclusion.
Answer: b) A realized niche.
Explanation: The bird is occupying a specific part of its possible habitats due to the limiting effects of competition, which defines its realized niche.
17. When two species divide resources to minimize competition, this is known as:
a) Resource partitioning.
b) Niche overlap.
c) Competitive exclusion.
d) Symbiosis.
Answer: a) Resource partitioning.
Explanation: Resource partitioning occurs when species use different resources or the same resources in different ways to reduce competition.
18. The realized niche of a species can be expanded by:
a) Eliminating all predators.
b) Evolutionary adaptation to new conditions.
c) Increasing the number of competitors.
d) Reducing available resources.
Answer: b) Evolutionary adaptation to new conditions.
Explanation: Evolutionary adaptations can allow species to exploit new resources or tolerate new environmental conditions, expanding their realized niche.
19. How can environmental changes affect a species’ realized niche?
a) Environmental changes can cause the species to adapt and expand its realized niche.
b) Environmental changes have no effect on the realized niche.
c) Environmental changes always shrink the realized niche.
d) Environmental changes can lead to the disappearance of the fundamental niche.
Answer: a) Environmental changes can cause the species to adapt and expand its realized niche.
Explanation: Environmental changes can lead to evolutionary adaptations that may allow a species to expand its realized niche or occupy new areas.
20. If two species share a similar ecological niche, but one species is more efficient at exploiting resources, the less efficient species will:
a) Expand its realized niche.
b) Adapt and become more efficient.
c) Be excluded from the niche.
d) Coexist without issue.
Answer: c) Be excluded from the niche.
Explanation: According to the competitive exclusion principle, the less efficient species will be outcompeted and may be excluded from the niche by the more efficient species.
21. The difference between a fundamental niche and a realized niche is primarily due to:
a) Genetic variation.
b) Abiotic conditions.
c) Biotic factors like competition and predation.
d) Evolutionary pressures.
Answer: c) Biotic factors like competition and predation.
Explanation: The realized niche is shaped by biotic factors such as competition and predation, which limit the range of conditions under which a species can live.
22. An example of a realized niche would be:
a) A plant species that can survive in both dry and wet conditions but only grows in wet conditions due to competition.
b) A fish species that can live in both freshwater and saltwater environments.
c) A bird species that can live in forests but only in areas without predators.
d) A bacteria that can survive in extreme conditions like high heat or radiation.
Answer: a) A plant species that can survive in both dry and wet conditions but only grows in wet conditions due to competition.
Explanation: The realized niche of the plant is influenced by competition, limiting it to wet conditions despite the broader range of conditions it could survive in (fundamental niche).
23. What would most likely occur if two species with overlapping niches are introduced to the same environment?
a) Both species will occupy different niches.
b) One species will be driven to extinction.
c) Both species will evolve to become more similar.
d) Both species will thrive equally.
Answer: b) One species will be driven to extinction.
Explanation: In cases of niche overlap, one species often outcompetes the other, leading to the exclusion of the less competitive species from that niche.
24. Which of the following is NOT a characteristic of a fundamental niche?
a) It represents the potential range of habitats a species could occupy.
b) It is unaffected by competitors and predators.
c) It is based only on abiotic factors.
d) It is smaller than the realized niche.
Answer: d) It is smaller than the realized niche.
Explanation: The fundamental niche is usually larger than the realized niche, as the realized niche is restricted by biotic factors.
25. Which term refers to the partitioning of environmental resources between competing species to reduce competition?
a) Niche differentiation.
b) Ecological isolation.
c) Coexistence.
d) Symbiosis.
Answer: a) Niche differentiation.
Explanation: Niche differentiation occurs when species evolve or adjust to using different resources or exploiting them in different ways, minimizing competition.
26. A species’ ability to exploit its fundamental niche is often restricted by:
a) The availability of food.
b) The presence of other species.
c) Natural disasters.
d) Temperature extremes.
Answer: b) The presence of other species.
Explanation: The presence of predators, competitors, and pathogens can restrict a species to its realized niche, even if its fundamental niche is larger.
27. The process by which a species adapts to occupy a specific portion of its fundamental niche is called:
a) Competitive exclusion.
b) Resource partitioning.
c) Niche overlap.
d) Evolutionary diversification.
Answer: b) Resource partitioning.
Explanation: Resource partitioning occurs when species evolve to exploit different resources or the same resource in different ways, reducing competition.
28. Which of the following statements is true about the realized niche?
a) It represents all the areas where a species could potentially survive.
b) It is unaffected by competitive or predatory pressures.
c) It is a portion of the fundamental niche that is occupied due to competition and other biotic factors.
d) It includes only abiotic factors.
Answer: c) It is a portion of the fundamental niche that is occupied due to competition and other biotic factors.
Explanation: The realized niche is the part of the fundamental niche that a species actually occupies, influenced by interactions with other species.
29. A species that thrives only in a very specific habitat due to competition with other species is occupying its:
a) Fundamental niche.
b) Realized niche.
c) Evolutionary niche.
d) Functional niche.
Answer: b) Realized niche.
Explanation: The species is occupying its realized niche because competition restricts it to a specific habitat rather than the broader range it could theoretically occupy.
30. What is one way that environmental change can alter a species’ realized niche?
a) By eliminating all competitors.
b) By reducing predation pressure.
c) By increasing resource availability.
d) By causing the species to become extinct.
Answer: c) By increasing resource availability.
Explanation: Environmental changes that increase resource availability can expand the realized niche, allowing a species to occupy new areas or utilize resources previously unavailable to it.
