A situation where a large cohort of women of reproductive age will fuel population growth over the next generation, even if each woman has fewer children than the previous generation did, is called:
Population Momentum
Understanding population dynamics involves several key concepts that describe how populations change over time. The question describes a specific scenario related to population growth that occurs due to the age structure of the population.
Analyzing Population Concepts
Let's look at the terms provided in the options to understand what each one means:
- Fertility Rate: This broadly refers to the number of live births per 1,000 women of reproductive age (usually 15-49) in a given year. It's a measure of how many births are happening relative to the number of women who could potentially have children.
- Total Fertility Rate (TFR): This is a more specific measure. It's the average number of children a woman is expected to have over her lifetime if she were to experience the current age-specific fertility rates throughout her reproductive years. A TFR of around 2.1 is generally considered the replacement level in developed countries (accounting for mortality before reproductive age).
- Population Momentum: This occurs when a population continues to grow even after the total fertility rate has fallen to or below replacement level. This happens because there is a large proportion of people currently in or entering their reproductive years (a large young cohort). Even if these individuals have fewer children on average than previous generations, the sheer number of potential parents leads to a continued increase in the total number of births and thus, the population size, for several decades.
- Population Growth: This is the overall increase in the number of people in a population over a specific period. It can be influenced by fertility, mortality, and migration. Population momentum is a *cause* of population growth in certain demographic structures, but it is not the mechanism itself.
Identifying the Correct Concept
The scenario described in the question highlights two crucial elements:
- A large cohort of women of reproductive age.
- Continued population growth over the next generation even if each woman has fewer children (implying a potentially lower fertility rate compared to the past).
This exact situation is the definition of Population Momentum. It is the built-in future growth in a population that results from a disproportionately large number of young people who are or will soon be entering the childbearing years.
Even if fertility rates drop, the large base of young people having children means the absolute number of births remains high for a time, driving population growth.
Comparing the Options
| Concept | Definition | Fits the Scenario? |
|---|---|---|
| Fertility Rate | Births per 1,000 women of reproductive age. | Measures births, but not the scenario of continued growth due to age structure despite potentially lower individual fertility. |
| Total Fertility Rate | Average number of children per woman. | Measures fertility level, but not the phenomenon of growth fueled by age structure when TFR might be low. |
| Population Momentum | Continued population growth despite replacement-level or lower fertility, caused by a large young population entering reproductive age. | Yes. This precisely describes the situation with a large cohort fueling growth even with lower individual fertility. |
| Population Growth | Overall increase in population size. | This is the outcome, not the specific demographic mechanism described involving the age structure and past high fertility. |
Based on the definitions and the analysis of the scenario, the situation where a large group of young women drives future population growth even with potentially lower fertility rates is known as Population Momentum.
Revision Table: Understanding Population Growth Factors
| Factor | Description | Impact on Population Size |
|---|---|---|
| Fertility | Number of births | Increases population |
| Mortality | Number of deaths | Decreases population |
| Migration (Immigration) | People moving into a region | Increases population |
| Migration (Emigration) | People moving out of a region | Decreases population |
| Population Momentum | Growth resulting from a large base of young people from past high fertility, even if current fertility is lower. | Causes continued growth for a period. |
Additional Information on Population Momentum and Demographics
Population momentum is a critical concept in demographic studies and population projections. It explains why populations in countries with a history of high fertility and a young age structure continue to grow for decades after fertility rates decline. Even if couples only have two children on average (replacement level), the large number of women entering their reproductive years means the total number of births remains high. This effect only diminishes as the large cohorts age and pass through the reproductive years. Policies aimed at stabilizing population size often need to consider the effects of population momentum, as achieving replacement-level fertility does not lead to immediate population stabilization.
Understanding population momentum helps in planning for future resource needs, infrastructure, and social services, as the population size will continue to increase for a significant time due to the age structure alone.
Important Questions from Social Change and the Economy
The type of demography that enquires into the wider causes and consequences of social structures and processes on population is called:
Who wrote the book “The Wealth of Nations”?
Liberalisation can be understood as:
Community Identity is based on:
Which of the following is not Sanskritisation?
