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प्रश्न
With the help of neatly labelled diagrams, explain the different types of age pyramids of human population.
उत्तर
The three different types of age Pyramids for human population are:
- Expanding or triangular age pyramids of human population:
- A large proportion of pre-reproductive individuals exist in the expanding population.
- The graph is triangular, with an extremely wide base and a pointy apex.
- Each age group shows a bar less wide than that of the age group before it, indicating that more people die in each higher group.
- The high birth rate in the vast base is likely attributable to variables such as a developing economy, poverty, low female education, and lack of information about birth control options.
- This type of population increase is seen in countries like India and Brazil.
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Stable age or bell-shaped age pyramid of human population:
- In a stable population, individuals who have not yet reached reproductive age exhibit uniform characteristics.
- The population distribution is depicted as rectangular or squarish on a graph, with nearly equal numbers across all age groups.
- A slight narrowing at the top is natural, reflecting a higher incidence of deaths among the elderly.
- This demographic pattern is commonly seen in countries with elevated life expectancies, where a significant portion of the population enjoys a longer lifespan due to improved living conditions. Examples of countries with this type of population growth include Denmark and the USA.
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Constructive or declining age pyramid of human population:
- There is a greater representation of individuals in the reproductive age category compared to those in the pre-reproductive age group.
- It pertains to populations that are decreasing or experiencing negative growth.
- Countries exhibiting this trend boast an elevated life expectancy, with a significant portion of the population living to an advanced age, thanks to improved living conditions.
- This demographic pattern is evident in nations such as Japan.
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