The World Population

2.1 Core concepts

• Population is real wealth. People are "the actual resources" who use a country's other resources and decide its policies — "ultimately a country is known by its people" (NCERT Introduction, p. 7). NCERT opens with Ralph Waldo Emerson's verse "Not gold but only (Wo)men can make a people great and strong" to frame people, not minerals, as the chief national asset.
• World population scale. At the beginning of the 21st century the world recorded the presence of over 6 billion population (NCERT Introduction, p. 7).
• Uneven distribution. Population is unevenly distributed; George B. Cressey's remark on Asia — "Asia has many places where people are few and few place where people are very many" — applies to the world as a whole (NCERT §Patterns of Population Distribution, p. 7).
• 90/10 rule. Broadly, 90 per cent of the world population lives in about 10 per cent of its land area (NCERT §Patterns of Population Distribution, p. 7).
• Top 10 share. The 10 most populous countries contribute about 60 per cent of the world's population; 6 of these 10 lie in Asia (NCERT §Patterns of Population Distribution, p. 7; Fig. 2.1). The bar chart in Fig. 2.1 ranks the top-10 in this order: China, India, USA, Indonesia, Brazil, Pakistan, Nigeria, Bangladesh, Russia, Mexico — with China and India each above 1,200 million.
• Density definition & formula. Density of Population = Population ÷ Area, expressed in persons per sq km; the worked example uses 1,50,000 persons in 100 sq km giving 1,500 persons/sq km (NCERT §Density of Population, p. 8). Each unit of land has a "limited capacity to support people living on it" — hence the ratio is essential.
• Geographical factors — water. Fresh water for drinking, bathing, cooking, cattle, crops, industries and navigation makes river valleys among the most densely populated areas of the world (NCERT §Factors I(i), p. 8).
• Geographical factors — landforms. Flat plains and gentle slopes favour cropping, roads, industry; the Ganga plains are densely populated while the Himalayan mountain zones are scarcely populated; mountainous areas hinder transport networks and discourage agricultural and industrial development (NCERT §Factors I(ii), p. 8).
• Geographical factors — climate. Extreme hot/cold deserts are uncomfortable for human habitation; areas with comfortable climate and little seasonal variation attract more people; very heavy rainfall or harsh climates produce low population; Mediterranean regions were inhabited from early periods of history due to their pleasant climate (NCERT §Factors I(iii), p. 8).
• Geographical factors — soils. Fertile loamy soils support intensive agriculture and therefore higher densities (NCERT §Factors I(iv), p. 8).
• Economic factors — minerals. Mineral deposits attract industries; mining and industrial activities generate employment so skilled and semi-skilled workers move to these areas; the Katanga–Zambia copper belt in Africa is the standard example (NCERT §Factors II(i), p. 8).
• Economic factors — urbanisation. Cities attract migrants through jobs, education, medical care, transport, communication and civic amenities, causing rural-to-urban migration; mega-cities of the world continue to attract large numbers of migrants every year (NCERT §Factors II(ii), p. 8).
• Economic factors — industrialisation. Industrial belts pull factory workers plus transport operators, shopkeepers, bank employees, doctors, teachers and other service providers; the Kobe–Osaka region of Japan is "thickly populated because of the presence of a number of industries" (NCERT §Factors II(iii), pp. 8–9).
• Social/cultural factors. Religious or cultural significance attracts people; social/political unrest repels them; governments may give incentives to populate sparsely populated areas or move people away from overcrowded places (NCERT §Factors III, p. 9).
• Population growth/change. Change of inhabitants of a territory over a specific period; positive or negative; expressed in absolute numbers or percentage; an indicator of economic development, social upliftment and historical/cultural background (NCERT §Population Growth, p. 9). The illustrative computation: India 2001 (102.70 crore) and 2011 (121.02 crore) give an absolute growth of 18.15 crores.
• Key formulae. Natural Growth = Births − Deaths; Actual Growth = Births − Deaths + In-migration − Out-migration (NCERT box "Some Basic Concepts of Population Geography", p. 9).
• Positive vs negative growth. Positive when birth rate exceeds death rate or there is in-migration; negative when birth rate falls below death rate or people emigrate (NCERT box, p. 9).
• Three components of population change — births, deaths and migration (NCERT §Components of Population Change, p. 9).
• CBR. Crude Birth Rate = (B/P) × 1000, live births in a year per thousand of mid-year population (NCERT §Components, p. 9).
• CDR. Crude Death Rate = (D/P) × 1000; mortality is shaped by demographic structure, social advancement and economic development; population growth occurs not only by increasing birth rates but also by decreasing death rates (NCERT §Components, p. 9).
• Migration vocabulary. Place of Origin loses population, Place of Destination gains; migration may be permanent, temporary or seasonal, and rural–rural, rural–urban, urban–urban or urban–rural; the same person is simultaneously an immigrant (moves in) and an emigrant (moves out); migration may be interpreted as "a spontaneous effort to achieve a better balance between population and resources" (NCERT §Migration, p. 10).
• Push factors. Unemployment, poor living conditions, political turmoil, unpleasant climate, natural disasters, epidemics, socio-economic backwardness (NCERT §Migration, p. 10).
• Pull factors. Better jobs and living conditions, peace and stability, security of life and property, pleasant climate (NCERT §Migration, p. 10).
• Scale of growth (Do You Know box, p. 10). Human population increased more than ten times in the past 500 years; in the 20th century alone it grew four times.
• Demographic Transition Theory — Stage I (High Fluctuating). High fertility AND high mortality; slow growth; agrarian society reproduces more to compensate for deaths from epidemics and variable food supply; large families are an asset; low life expectancy, illiteracy, low technology; 200 years ago all countries of the world were in this stage (NCERT §Demographic Transition, p. 10; Fig. 2.2).
• Demographic Transition Theory — Stage II (Expanding). Fertility remains high at the beginning then declines while mortality falls due to improvements in sanitation and health; the gap produces high net addition to population (NCERT p. 11).
• Demographic Transition Theory — Stage III (Low Fluctuating). Both fertility and mortality are low; population stable or grows slowly; society is urban, literate, technologically advanced and consciously controls family size; "human beings are extremely flexible and are able to adjust their fertility" (NCERT p. 11).
• Country examples on Fig. 2.2. Stage I — Bangladesh, Rainforest tribes; Stage II — Peru, Sri Lanka, Kenya; Stage III — Canada, Japan, USA (NCERT Fig. 2.2, p. 10).
• Rural-Agrarian → Urban-Industrial. The demographic cycle is the linking process by which a society moves from one extreme to the other (Fig. 2.2 inset diagram, p. 10).
• Population control. Family planning — spacing or preventing births — is key; propaganda, free contraceptives and tax disincentives for large families are control measures; access to family planning services is significant in limiting population growth and improving women's health (NCERT §Population Control Measures, p. 11).
• Malthus (1798). Population would grow faster than food supply; further increase would cause a population crash via famine, disease and war; preventive checks are better than physical checks; for sustainability the world will have to control rapid population increase (NCERT §Population Control Measures, p. 11).

2.2 Definitions to memorise

2.3 Diagrams / processes to remember

• Fig. 2.1 Most Populous Countries (p. 7): horizontal bar chart with population in millions on x-axis. Order from largest: China, India, USA, Indonesia, Brazil, Pakistan, Nigeria, Bangladesh, Russia, Mexico. The six Asian countries among the top 10 are China, India, Indonesia, Pakistan, Bangladesh and (depending on counts) Japan; the NCERT prompts the student to identify them.
• Density formula box (p. 8): Density = Population/Area, illustrated by 1,50,000 ÷ 100 = 1,500 persons/sq km.
• Rural-Agrarian → Demographic Transition → Urban-Industrial flow arrow (p. 10): captures the essence of the theory in one line.
• Fig. 2.2 Demographic Transition Theory (p. 10): three-stage curve with BR (birth rate) starting near 35 and DR (death rate) also high in Stage I (High Fluctuating), DR falling steeply in Stage II (Expanding) while BR lags, both flattening near 15 in Stage III (Low Fluctuating); shaded "Natural Increase in Population" wedge between the two curves in Stage II; country labels along the time axis: Bangladesh / Rainforest tribes (I), Peru / Sri Lanka / Kenya (II), Canada / Japan / USA (III).
• Some Basic Concepts box (p. 9): prints the definitions of Growth, Growth Rate, Natural Growth, Actual Growth, Positive Growth and Negative Growth side by side with formulae.
• Do You Know box (p. 10): records that human population grew more than 10 times in the past 500 years, and 4 times in the 20th century alone.

2.5 Key data table (chapter facts at a glance)

2.4 Common confusions / NTA trap points

• Immigrant vs Emigrant — moving IN = immigrant; moving OUT = emigrant. NTA loves swapping the two.
• Natural growth vs Actual growth — natural ignores migration (only births − deaths); actual includes net migration.
• Push vs Pull — push REPELS from origin (unemployment, epidemics, water shortage); pull ATTRACTS to destination (medical/educational facilities, jobs, security). Exercise 1(iii) is exact: "medical/educational facilities" is NOT a push factor.
• Stages of demographic transition — population growth is SLOW in Stage I (both BR and DR high) and Stage III (both low); growth is FASTEST in Stage II. Exercise 1(iv) tests the false claim that growth is high in Stage I.
• 90/10 distribution — 90% of people on 10% of land, NOT the other way around.
• Top-10 share — about 60% of world population, not 90% or 50%.
• Katanga–Zambia is a COPPER belt (not coal/iron) and an example of MINERAL-driven density, not industrialisation per se.
• Kobe–Osaka is the standard example for INDUSTRIALISATION (not urbanisation alone).
• Malthus (1798) said food grows slower than population and proposed PREVENTIVE checks as better than physical (positive) checks.
• Sparse-population areas (Exercise 1(ii)) — Atacama (cold desert), equatorial region (very heavy rainfall), polar regions are sparse; South-east Asia is NOT sparse — it is dense.
• Highest-growth continent (Exercise 1(i)) — Africa, not Asia.
• **CBR/CDR are *per 1,000***, not per 100 — multiplying by 100 gives a percentage, not a rate.
• Six Asian countries in top 10 is the NCERT count; CUET sometimes tests "how many Asian countries" — the right answer is 6.