Which of the following contributes an increase in population density ?

Options

A. Mortality
B. Emigration
C. Natality
D. Predation

Answer

To determine which of the following contributes to an increase in population density, we will analyze each option: mortality, emigration, natality, and predation.

### Step-by-Step Solution:

1. **Understanding Mortality**:
- Mortality refers to the death rate in a population, which is the ratio of the number of deaths to the size of the population.
- When mortality increases, the number of individuals in the population decreases.
- **Conclusion**: Mortality contributes to a decrease in population density.

2. **Understanding Emigration**:
- Emigration is the process where individuals leave their native region to move to another area.
- When individuals emigrate, the population size in the original area decreases.
- **Conclusion**: Emigration also contributes to a decrease in population density.

3. **Understanding Natality**:
- Natality, also known as birth rate, refers to the number of births in a population over a specific period.
- An increase in natality means more individuals are being born, which increases the population size.
- **Conclusion**: Natality contributes to an increase in population density.

4. **Understanding Predation**:
- Predation involves one organism killing and consuming another.
- Increased predation leads to a decrease in the population size of the prey species.
- **Conclusion**: Predation contributes to a decrease in population density.

### Final Answer:
The option that contributes to an increase in population density is **natality**.

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