How can we explain the fact that 40 percent of the world lives in only two countries?
Abstract:
India and China together hold 20% of world’s arable land (land suitable for a major crop), producing 50% of the world’s rice and 30% of the world’s wheat. They are spread around the Tropic of Cancer (a great zone for human settlement), were unified multiple times in the past (leading to a large land area under one flag), got to the major cereals earlier (rice & wheat), got the benefit of other civilizations nearby (borrowing ideas of wheel & writing systems) and were spared from many of the major human calamities & migrations of history.
Climate and Geography:
Although India & China occupy “only” a tenth of Earth’s land surface, their share of earth’s hospitable land is close to a quarter. Vast chunks of earth are not really hospitable — Siberia, Antarctica, Greenland, Alaska, Sahara desert, most of Canada, Arabian desert and rain forests of Amazon and central Africa. The inland water resources of Mongolia, northern Mexico, central Australia, Central Asian Republics are too few. This rules out a sizable chunk of earth’s land for dense human settlement.
The region around the Tropic of Cancer and the Tropic of Capricorn is the best suited for human settlement (see below). A big chunk of this region is lost in the Sahara, leaving India, Mexico, Southern US & China as the major non-arid regions on this zone. In the southern hemisphere most of this critical zone is taken over by oceans or deserts (Kalahari, Great Victoria, Atacama).
Those small portions of land near Tropic of Capricorn not occupied by the ocean support the major southern metropolises of Sydney, Capetown, Beunos Aires, Melbourne, Sao Paulo, Rio de Janerio and Santiago.
Water and Silt:
Let us now zoom to this critical zone around 30N (just north of Tropic of Cancer) where all major civilizations arose and almost all of modern religions came from. The people around this latitude shaped the world’s history of ancient era.
While Iran had civilizations going from the ancient era, it never had any major river to support a massive population growth. Israel was too small & had a constant outside intervention. Egypt outside the narrow Nile valley, most of Iraq (especially regions far from Tigris & Euphrates) and most parts of Arab peninsula were too dry & hot to support massive population settlement.
Northern India and Eastern China sit on massive alluvial plains created by rivers such as Ganga+Indus and Huang He+Yangtze rivers. The first recorded human civilizations grew on these river valley plains along with the plains created by Nile (Egypt) and Euphrates (modern Iraq). These river valleys provided the right conditions for the civilization, with water & silt for agriculture, tolerable climatic conditions and rivers for commerce.
There are only a handful of these big river valleys in the world, especially in this latitude. Overall there are about 26 major river basins (see map below) and only 16 of them are in the hospitable regions. India and China have 4 of the 16. Of the remaining 12, five of them are surrounded by massive rain forests. Three of them: Orange, Murray-Darling & Mississippi were a bit isolated to support a major civilization (although they all supported unique native cultures and are home to major cities now). That leaves the Nile, Danube, the Euphrates, Zambezi as the major cradles of civilizations outside India & China.
Besides the major ones, China has 50,000 rivers with 100sq km or more in the catchment area. India has a lesser number of these rivers, but is well spread throughout the country. The rivers are neither too monstrous like the Amazon nor too small to feed the population. The following river map is unusual among any country in this zone and enabled multiple regions of population concentration.
In short India and China had multiple river systems that were both massive as well as hospitable that lead to huge food production. Instead of depending on a single river system (like Egypt), India and China each had more than 3 major river systems giving a sort of backup. Thus, when Indus valley civilization faltered, the civilization quickly picked up the slack near Ganges.
Food production:
In 2005, India and China together held 20% of world’s arable land (land suitable for a major crop), producing 50% of world’s rice and 30% of world’s wheat. Land use statistics by country. This ratio would have been much higher two centuries ago when vast tracts of Brazil, Sibera, Australia and USA were not explored. While 50% of India is arable, less than 7% of Australia, Canada or Russia is arable even with the introduction of modern technology.
Remember that food and water were the most critical for previous civilizations. Only in the modern era, these became slightly less important. But, by then the drop in fertility rates (from literacy) and migration restrictions made population growth slow in the US & Europe.
Connectivity & Idea sharing
Mississippi had a nice river valley system that was in the same latitude & had all the right climatic conditions (other than the hurricanes & typhoons). Indeed, it supported a rich Native American culture. However, it never had the population density of Ganges or Yangtze river valleys.
One reason could be the fact that humans migrated there much later than in Asia (12000 BC vs. 70000 BC) leaving them less time to succeed in a trial-and-error manner.
The Mississippi river valley never had the benefit of other major civilizations close to it. Asian civilizations exhibited a lot of connectivity. The pottery technology of Indus, wheel of Sumer, writing system of Egypt and later the religion of Ganges (Buddhism) quickly spread to other civilizations enabling people to build ideas on top of best practices elsewhere. When the Europeans came most of this population got decimated and thus US never had a population to rival Asia.
US population recovered only when Europeans started settling down and started to bring the best practices in other civilizations. US started exploding since 16th century, growing 60X since 1800. US is actually catching up. But, India and China have a huge headstart.
Size & Organization
India and China are dense as well as huge. Parts of western Europe and Southeast Asia have density comparable to India & China, but was not unified for a sufficient period of time.
Both India and China were fortuitous to have been unified for sizable chunks of time since about 200 BC. Qin Dynasty unified China in about 206 BC and Ashoka unified India in about 250 BC. Since then, the Chinese had been unified under the Yuan, Ming and Qing dynasties while India had been unified under the Mauryas, Guptas, Mughals and later the East India company. (Coincidentally both Mughals and Qings — the last native empires of India & China were outsiders who got assimilated into the respective cultures).
However, the native American settlements in the Mississippi river valley and elsewhere were never unified in a major way nor were organized.
Crops & food
China domesticated Rice in about 10000 BC and rice quickly moved to South & Southeast Asia. At about the same time, Wheat was domesticated and moved from West Asia towards India. Thus, both India and China had access to massive cereal crops.
In contrast, both Europe and Africa had relatively less access to major cereals. Major cereals reached Europe relatively late and until recently Africa had no major cereal group that lent itself to massive farming. Even today, Africa’s cereal yield outside of Nile valley and South Africa is very poor.
Major epidemics, migrations & wars
In 540 AD the Plague of Justinian ravaged Europe and decimated cities like Constantinople. 50% of Europe perished in that plague. In 1346 the Bubonic plague (Black Death) killed 30-60% of all Europe. Between 16th and 19th centuries sizable parts of Europe emigrated to the Americas, Africa, Asia and Australia. The World Wars and the drop-in fertility in the 20th century (with better education) kept Europe’s population further in check.
Iran lost 90% of its population in the Mongol invasion of Central Asia. Native Americans were decimated by Small pox and other old world diseases brought by European settlers.
While China had some major disasters (such as the Mongol invasion and plague) its population was sizable enough to recover from them & was fairly sparred since 1300s. India escaped Genghiz Khan’s warriors and the Bubonic plague. Until the coming of famines under the East India Company, major death tolls were relatively uncommon.
Also see:
Historical Estimates of World Population
World population estimates
