Which of the following is a density-independent factor affecting population growth?

• A. Predation
• B. Competition for resources
• C. Disease
• D. Natural disasters

Answer: (D)

Verified step by step guidance

1. Understand the concept of density-independent factors: These are factors that affect population size regardless of the population's density. They are typically abiotic factors such as weather, climate, and natural disasters.
2. Differentiate between density-dependent and density-independent factors: Density-dependent factors, such as predation, competition for resources, and disease, have effects that vary with the population density. In contrast, density-independent factors impact populations regardless of their size.
3. Identify examples of density-independent factors: Common examples include natural disasters like hurricanes, earthquakes, floods, and fires. These events can drastically reduce population sizes without regard to how many individuals are present.
4. Analyze the given options: Predation, competition for resources, and disease are all density-dependent factors because their impact increases with population density. Natural disasters, however, affect populations regardless of their density.
5. Conclude that natural disasters are a density-independent factor affecting population growth, as they can impact populations equally, whether they are large or small.