What do you mean by declining population ?

Explanation

### Step-by-Step Solution:

1. **Definition of Population**: A population is a group of individuals of the same species living in a specific area at a given time. Each population consists of individuals of various ages.

2. **Age Distribution**: The age distribution of a population can be represented using an age pyramid. This graphical representation shows the number of individuals in different age groups, typically divided by gender.

3. **Understanding Age Pyramids**: The shape of the age pyramid provides insights into the growth status of the population. It can indicate whether the population is growing, stable, or declining.

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