Problem 5 - Biology

Question

Divergence in morphology that is a result of competition is termed a. competitive exclusion. b. resource partitioning. c. character displacement. d. amensalism. e. mutualism.

Step-by-Step Solution

Answer

The correct answer is c. character displacement.

Step 1: Defining the Key Terms

First, let's define the key terms:\n\n- Competitive Exclusion: This principle suggests that two species competing for the same resources cannot coexist.\n\n- Resource Partitioning: This is a process where the natural environment selects species to use different resources or use the same resources in different ways to avoid competition.\n\n- Character Displacement: This is an evolutionary divergence in one or both of the species that leads to a partition of the niche to avoid competition, leading to a change in the species' physical characteristics or 'characters'.\n\n- Amensalism: This is a type of biological interaction where an organism is inhibited or destroyed while the other organism remains unaffected.\n\n- Mutualism: This is a symbiotic relationship where both organisms benefit.

Step 2: Identifying the Correct Term for the Given Definition

Given the definitions, the term that best fits the definition 'Divergence in morphology that is a result of competition' is Character Displacement. This is because character displacement leads to a change (or 'divergence') in physical characteristics (or 'morphology'), which is driven by competition.

Key Concepts

Competitive Exclusion

The principle of competitive exclusion asserts that two species competing for identical resources cannot stably coexist. This means, if two species rely on the same limited resource, one will generally prevail. The other may either adapt, migrate to a different habitat, or face extinction. This occurs because the superior competitor will utilize the resource more efficiently, causing the other species to decline.
Some outcomes of competitive exclusion include:

• Local extinction of the less competitive species.
• Ecosystem balance through niche differentiation.
• Adaptation leading to niche specialization.

Competitive exclusion thus emphasizes the importance of diversity in ecological niches, pushing organisms to exploit different aspects of the environment, reducing direct competition.

Resource Partitioning

Resource partitioning is a strategy where species adjust or alter their resource use to minimize competition. By utilizing different parts, times, or modes of a resource, species can coexist without one driving the other to extinction. This is a common outcome of the competitive exclusion principle in action.
Resource partitioning can manifest in several ways:

• Temporal partitioning, where species use the same resource at different times.
• Spatial partitioning, where species utilize different habitats or areas.
• Morphological differentiation, leading to adaptation in resource use.

This process fosters biodiversity by allowing similar species to thrive side by side, each carving out its niche in the ecosystem.

Amensalism

Amensalism is an ecological interaction where one organism is harmed while the other remains unaffected. Unlike predation or competition, the unaffected species neither benefits from nor is injured by the presence of the second species.
Examples of amensalism include:

• Tall trees that block sunlight from reaching plants below, inhibiting their photosynthesis.
• Fungi producing antibiotics that inhibit bacteria growth around them.

Amensalism can lead to suppression of specific species, affecting biodiversity and community structure. This interaction exemplifies the complexity of ecological relationships where not all interactions are direct or reciprocal.

Mutualism

Mutualism is a symbiotic relationship where both organisms involved benefit from the interaction. It is one of the key drivers of ecosystem health and stability, promoting cooperation and balance in nature.
Mutualistic relationships can take various forms, such as:

• The relationship between bees and flowers, where bees get nectar and flowers receive pollen transfer.
• Mycorrhizal fungi and plant roots, where fungi enhance nutrient uptake for the plant, and the plant provides carbohydrates to the fungi.

This interdependence increases survival, resilience, and adaptation of species, making mutualism crucial for maintaining biodiversity.