Define zero population growth

Explanation

**Step-by-Step Solution:**

1. **Understanding Population Dynamics**: Begin by recognizing that population dynamics involve the changes in the number of individuals in a population over time. This includes births, deaths, immigration, and emigration.

2. **Defining Zero Population Growth (ZPG)**: Zero population growth refers to a specific condition in a population where the number of births is equal to the number of deaths. This means that there is no net increase or decrease in the population size.

3. **Stability of Population**: In a state of zero population growth, the overall population remains stable. This stability indicates that the population is neither growing nor declining.

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