Question

When percentage of individuals of pre-reproductive, reproductive and post-reproductive phase is in decreasing order in the age pyramid of human population, it shows that population is

• A. Expanding
• B. Decreasing
• C. Stable
• D. Unstable

Hint:

Expanding populations have broad-based pyramids due to a higher percentage of young individuals.

Answer 1

The Correct Option is A

Step 1: Understanding age pyramids.
An age pyramid represents the distribution of individuals in different age groups of a population.
Step 2: Case of decreasing order.
When the proportion is highest in the pre-reproductive phase, followed by reproductive, and lowest in post-reproductive, it indicates more young individuals, ensuring future population growth.
Step 3: Analyzing options.
(A) Expanding: Correct — More young individuals mean the population is expanding.
(B) Decreasing: Incorrect — Would show fewer young and more old.
(C) Stable: Incorrect — All three groups would be nearly equal in proportion.
(D) Unstable: Incorrect — Not the correct ecological term in this context.
Step 4: Conclusion.
Hence, the population pyramid in decreasing order of age groups indicates an expanding population.