Population growth throughout history:
For 3 million years of human history, until the 1800s, human population was low (at least compared to today's figures): under a billion people, and growing slowly. This was due to high death rates which were due to disease, famine, and various other factors such as vulnerability to predators and the elements etc. Advances such as the agricultural revolution and the discovery of irrigation ploughing helped increase population growth slightly, but overall growth rates remained largely the same. It was only in the 1800s, because of the Industrial Revolution, that population started to grow exponentially at a rate never seen before, shooting past the billion mark for the first time in history. This was due to leaps in fields such as medical science, engineering, agriculture, industry, technology, etc. All these factors combined helped to curb the high mortality rates and increase life expectancy. This meant that more people were surviving to have children and this new "golden age" with higher life expectancy, food production and availability, and increased healthcare, encouraged people to have more children, which obviously contributed to the ever-rising population growth (growth rate was at around 1.8%,
an all-time high).
Population rise continued inexorably: in 1927 the 2 billionth baby was born. At this time population growth hovered at around 1% a year. Advents such as antibiotics and other public health advances ensured that yet more children would live to have their own children. In 1960, world population reached 3 billion. By now advances in medicine, agriculture and sanitation had spread to the developing world. Growth ratio was at an all-time peak of 2.04% a year. 14 years later, in 1974, global population reached 4 billion. New reproductive technologies were helping to curb the growth rate, but a population explosion was already underway with...