Population Composition (World)
Sex Composition
Sex composition refers to the number of females per 1,000 males in a population. It is a vital demographic indicator that reflects gender balance and provides insights into social, economic, and health conditions.
Natural Advantage V/s Social Disadvantage
The sex ratio at birth and throughout life is influenced by both natural biological factors and socio-cultural factors.
- Natural Advantage (Biological Factors):
- Sex Ratio at Birth: Globally, for every 100 females born, approximately 104 to 107 males are born. This is a natural biological phenomenon, possibly due to slight differences in the survival rates of sperm carrying the male (Y) chromosome or early embryonic development. This slight male bias at birth is generally considered a natural advantage for males.
- Sex-Specific Mortality Rates: Throughout most life stages, males tend to have higher mortality rates than females due to biological reasons (e.g., genetic predispositions, hormonal differences) and higher participation in riskier activities (e.g., certain occupations, warfare). This natural disadvantage for males often leads to a higher proportion of females in older age groups.
- Social Disadvantage (Socio-Cultural Factors):
- Gender Discrimination: In many societies, social, cultural, and economic factors can lead to a disadvantage for females, negatively impacting their sex ratio. This can manifest as:
- Female Foeticide and Infanticide: Preferential treatment for male births can lead to selective abortion of female fetuses or neglect of female infants.
- Differential Access to Healthcare: Females may have less access to healthcare, leading to higher mortality rates, particularly during childbirth or for specific diseases.
- Gender-Based Violence and Conflict: These can disproportionately affect women and girls.
- Riskier Lifestyles for Males: While biological factors might give females a survival advantage, societal factors like higher male participation in dangerous jobs, higher rates of accidents, suicide, and violence can sometimes offset this advantage, leading to more males dying at younger ages.
- Migration: Male migration for work can temporarily skew the sex ratio in certain areas (more males in destination, more females in origin).
- Gender Discrimination: In many societies, social, cultural, and economic factors can lead to a disadvantage for females, negatively impacting their sex ratio. This can manifest as:
Global Trends:
- Overall: Globally, there are slightly more males than females at birth, but females tend to outlive males, resulting in a more balanced or female-dominated sex ratio in older age groups. The overall global sex ratio is around 101 males per 100 females.
- Variations: Countries with strong cultural preferences for sons and less access to modern healthcare and education often exhibit significantly lower sex ratios (fewer females per male), indicating a social disadvantage for females.
Age Structure
Age structure refers to the proportion of the population in different age groups. It is a crucial determinant of a population's characteristics, influencing its growth potential, dependency ratio, and societal needs.
Age-Sex Pyramid
Definition: An age-sex pyramid (also known as a population pyramid) is a graphical representation of the distribution of a population by age and sex. It displays the percentage of males and females in different age cohorts (typically 5-year intervals).
Structure:
- The horizontal axis represents the percentage or number of males (usually on the left) and females (usually on the right) in each age group.
- The vertical axis represents age groups, starting from the youngest at the bottom and progressing to the oldest at the top.
Interpretation of Pyramid Shapes: The shape of the pyramid reveals significant information about a population's growth and characteristics:
Expanding Populations
Pyramid Shape: Broad base, tapering rapidly towards the top. Triangular shape.
Characteristics:
- High birth rate.
- High proportion of young people (0-14 years).
- Rapid population growth.
- Often found in developing countries with high fertility rates and falling mortality rates.
Example: Many countries in sub-Saharan Africa.
Constant Population
Pyramid Shape: More rectangular or bell-shaped, with fewer people in the youngest age groups compared to expanding populations, but still a substantial proportion of young people. The sides are more vertical in the middle age groups.
Characteristics:
- Low birth rate.
- Low death rate.
- Slow or zero population growth.
- More balanced age distribution.
- Often found in developed countries where fertility rates have declined significantly.
Example: Countries like the United States or Canada often exhibit this structure.
Declining Populations
Pyramid Shape: Narrow base, with a bulge in the middle and older age groups. The youngest age groups are smaller than the older ones.
Characteristics:
- Birth rate is lower than the death rate.
- A high proportion of elderly people.
- Population is shrinking.
- Found in countries with very low fertility rates and aging populations.
Example: Japan, some Eastern European countries.
Ageing Population
Definition: A population where a large proportion of individuals are in the older age groups (e.g., 65 years and above). This is a consequence of declining fertility rates and increasing life expectancy.
Characteristics:
- Low birth rates.
- Low death rates.
- Low or negative population growth.
- High dependency ratio due to the large elderly population.
- Increased demand for healthcare, pensions, and social support services.
Countries: Japan, Italy, Germany, and many other developed nations are experiencing significant population aging.
Rural Urban Composition
Rural-urban composition refers to the proportion of a population living in rural versus urban areas. This division is based on settlement patterns and infrastructure development.
- Rural Population: Typically lives in villages or small settlements away from major cities. Characterized by a greater dependence on agriculture, primary sector activities, and often lower population densities.
- Urban Population: Lives in cities and towns, characterized by higher population densities, a greater concentration of secondary and tertiary sector activities, and more developed infrastructure and services.
Global Trends:
- Urbanization: The world is experiencing rapid urbanization. More than half of the global population now lives in urban areas, and this proportion is projected to increase further. This shift is driven by migration from rural areas in search of better economic opportunities, education, and living standards.
- Impact of Urbanization: Urbanization leads to the growth of cities, often resulting in challenges like increased demand for housing, infrastructure, services, potential slum development, traffic congestion, and pollution. However, it also concentrates economic activity and innovation.
- Regional Variations: Developed countries have a higher proportion of urban population compared to developing countries, although the latter are urbanizing rapidly.
Literacy
Literacy is a fundamental aspect of population composition, reflecting the educational attainment and potential of a population.
- Definition: Literacy is the ability to read and write with understanding. It is usually measured as the percentage of the population aged 7 years and above who are literate.
- Significance:
- Social Development: Higher literacy rates are linked to greater awareness, better health practices, lower fertility rates, and increased social mobility.
- Economic Development: A literate workforce is crucial for skilled labor, technological advancement, and economic growth.
- Empowerment: Literacy empowers individuals, particularly women, to participate more fully in society and the economy.
- Global Variations: Literacy rates vary significantly worldwide. Developed countries generally have near-universal literacy, while some developing countries still face challenges in achieving high literacy rates, often due to poverty, lack of access to education, and gender disparities.
- Factors Affecting Literacy: Access to education, quality of schooling, government policies on education, socio-economic status, and gender equality.
Occupational Structure
Occupational structure refers to the distribution of the workforce across different economic sectors, indicating the level of development of a country or region.
- Primary Sector: Includes activities directly related to the extraction of natural resources, such as agriculture, forestry, fishing, mining, and quarrying. In less developed economies, a large proportion of the workforce is engaged in this sector.
- Secondary Sector: Includes activities related to manufacturing, processing, and construction. Industrialization leads to an increase in employment in this sector.
- Tertiary Sector: Includes activities related to services, such as trade, transport, communication, finance, healthcare, education, and administration. Developed economies typically have the highest proportion of their workforce engaged in the tertiary sector.
Development Indicator: The shift in occupational structure from primary to secondary and tertiary sectors is a key indicator of economic development. Countries with a higher proportion of workers in the tertiary sector are generally considered more developed.
Global Variations:
- Developed Countries: High percentage of workforce in the tertiary sector, followed by the secondary sector, and a small percentage in the primary sector.
- Developing Countries: A significant proportion of the workforce is often concentrated in the primary sector (especially agriculture), with smaller shares in the secondary and tertiary sectors, though the tertiary sector is often growing rapidly.