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Question
The following diagrams are the age pyramids of different populations. Comment on the status of these populations.
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Solution
Fig.A: It is a ‘pyramid’ shaped age pyramid. In this figure, the base i.e pre- reproductive stage is very large when compared with the reproductive and past reproductive stages of the population. This type of age structure indicates that the population would increase rapidly.
Fig.B: It is an ‘inverted bell’ shaped pyramid. In this figure, the pre-reproductive and reproductive stages are the same. This type of age structure indicates that the population is stable.
Fig.C: It is ‘Urn’ shaped pyramid. In this figure, the pre-reproductive and reproductive stages are less than the post-reproductive stage of this population. In this population more older people are present. This type of age structure indicates that the population definitely is declining.
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