Since the first humans appeared in Africa over two million years ago, the world’s population has increased, and only with short pauses for the growing number of people inhabiting the planet.
With the world population growing to 8 billion, expected to be reached in mid-November, AFP is looking at key milestones in human growth.
First people
The oldest fossils of the oldest known people date back to 2.8 million years old and were found in East Africa.
But estimates of the number of people who inhabited this land remained largely unreliable until the 19th century. What we do know is that our ancestors were hunter-gatherers and had few children compared to later settled populations to support their nomadic lifestyle.
The planet’s population was also small, in part because hunters and gatherers need a lot of land to feed themselves — about 10 square kilometers per capita, according to Herve Le Bras, a researcher at the French Institute for Explorations in Demographics (INED).
The population of the world grew over time, but very slowly.
First baby boom
The introduction of agriculture during the Neolithic period, around 10,000 BC, led to the first known significant population surge.
With agriculture came settlements and the ability to store food, resulting in a high birth rate.
“Mothers have been able to feed their babies oatmeal, which speeds up the weaning process and shortens the time between births, which means more babies per woman,” Le Brass explained.
The development of permanent settlements also comes with risks, as the domestication of animals causes new deadly diseases for humans.
The infant mortality rate was particularly high, with a third of children dying before their first birthday and another third before the age of 18.
“There were mass deaths, but there was also a permanent baby boom,” explains Eric Crobesi, an anthropologist at the University of Toulouse in France.
According to estimates from the National Institute for Economic Research, from 6 million people in 10,000 B.C. world population jumped to 100 million in 2000 BC and then to 250 million in the first century AD.
Black Death
The Black Death suddenly stopped the population boom in the Middle Ages.
The epidemic, which appeared in Central Asia, on the territory of modern Kyrgyzstan, reached Europe in 1346 on ships carrying goods from the Black Sea.
In just eight years, he destroyed up to 60% of the population of Europe, the Middle East and North Africa.
As a result of the Black Death, the population declined between 1300 and 1400 from 429 million to 374 million.
Other events, such as the Plague of Justinian that struck the Mediterranean over the course of two centuries from 541 to 767, and the wars of the early Middle Ages in Western Europe, caused a temporary decline in the number of people on Earth.
Eight billion and the number is increasing
Starting in the 19th century, the population began to grow rapidly, mainly due to the development of modern medicine and the industrialization of agriculture, which increased the world’s food supply.
Since 1800, the world’s population has increased eightfold, from an estimated one billion to eight billion.
The development of a vaccine was key, especially the smallpox vaccine helped lash out at one of the biggest killers in history.
The 1970s and 1980s brought another small revolution in the form of heart disease treatment, which helped reduce mortality in people over 60 years of age.
Source: Science Alert.
