Living Environment Regents Practice Test

Which factor is essential for the growth of diverse species within an ecosystem?

1. High population density of each species

2. Legal protection of all species

3. Existence of various niches

4. Stable temperature conditions

The correct answer is: Existence of various niches

The existence of various niches is crucial for the growth of diverse species within an ecosystem. A niche refers to the specific role or function that a species has in its environment, which encompasses its habitat, resource use, and interactions with other organisms. When a variety of niches are available, it allows for different species to coexist while minimizing competition for resources. Each species can adapt to its own niche, leading to greater biodiversity. In ecosystems where multiple niches exist, species can exploit different food sources, occupy different habitats, or have varying reproductive strategies, ultimately contributing to a more resilient and balanced ecosystem. This diversity enhances ecological stability, enabling the ecosystem to withstand changes and disturbances better. Other factors, while relevant, may not be as directly influential on the diversity of species as the presence of various niches. For example, high population density can lead to competition, whereas legal protection might help conserve species but doesn’t necessarily promote diversity in the way that niche variety does. Similarly, stable temperature conditions can create favorable environments but do not inherently guarantee biodiversity without the presence of diverse niches.