Since the first humans appeared in Africa more than 2 million years ago, the world’s population has increased dramatically with only short pauses before increasing the number of people living on planet Earth. As the world’s population reaches 8 billion—a milestone expected to be reached in mid-November—AFP examines the key stages of human development.

first people

The earliest fossils of the earliest known humans date back 2.8 million years and have been found in East Africa. However, estimates of the number of people living on Earth remained highly unreliable until the 19th century. What we do know is that our ancestors were hunter-gatherers who had very few children compared to later settled populations to support their nomadic lifestyle.

According to Hervé Le Bra, a researcher at the French Institute for Demographic Studies (INED), the global population was sparse, in part because hunter-gatherers needed so much land to feed themselves—about 10 square kilometers per person. The world’s population has grown over time, but very, very slowly.

first baby boom

The introduction of agriculture in the Neolithic era, around 10,000 BC, provided the first known large population increase. With agriculture came settlement and the ability to store food, which led to a rapid increase in the birth rate.

“Mothers can give their babies porridge, which speeds up the weaning process and shortens the time between deliveries, which means more babies per woman,” Le Bras said.

The development of permanent settlements was also a danger, but the domestication of animals caused humans to contract new deadly diseases. Infant mortality was particularly high, with one-third of all children dying before their first birthday and one-third by the time they reach 18.

“There was a huge mortality rate, but there was also a sustained baby boom,” said anthropologist Eric Crubesy of the University of Toulouse in France.

According to INED estimates, the world’s population jumped from about 6 million in 10,000 BC to 100 million in 2000 BC and then to 250 million in the first century AD.

Black Death

The Black Death brought the population to a sudden halt in the Middle Ages. The epidemic, which emerged in Central Asia on the territory of modern Kyrgyzstan, reached Europe in 1346 by ships carrying goods from the Black Sea. It wiped out 60 percent of the population of Europe, the Middle East and North Africa in just eight years. As a result of the Black Death, the human population fell from 429 to 374 million between 1300 and 1400. Other events, such as the Plague of Justinian that struck the Mediterranean for two centuries from 541 to 767, and the early medieval wars in Western Europe, also caused temporary declines in the number of people on Earth.

Eight billion and beyond

From the 19th century, the population began to increase dramatically, mainly due to the development of modern medicine and the industrialization of agriculture, which contributed to the increase in the global food supply. Since 1800, the world’s population has increased eightfold, from about 1 billion to 8 billion. For Krubezi, vaccine development was key, especially with the smallpox vaccine helping to kill one of the biggest killers in history. The 70s and 1980s brought another minor revolution in the form of heart disease treatment that helped reduce the death rate among people over 60. Source