The Sahara Desert, the largest desert on the planet, was not always a barren and inhospitable environment. Around 12,000 years ago, the climate warmed up, and the Sahara became a green and fertile region, home to diverse populations of humans, plants, and animals. This period, known as the "Green Sahara," lasted for several millennia and was characterized by regular rains, numerous rivers, and lakes. Humans in this region developed a lifestyle centered around fishing, hunting, and breeding cattle. However, around 4,000 years ago, the climate cooled down, and the Sahara began to dry out again, leading to the disappearance of the lakes and rivers. The populations of the Sahara were forced to adapt to the new environment, and many migrated to other regions, contributing to the formation of the Old Kingdom in Egypt. Today, the Sahara remains a challenging environment, but there are hopes that the warming of the ocean could lead to increased rainfall and the return of vegetation to the region.
Here are the key facts extracted from the text:
1. The Sahara is the largest desert on the planet.
2. The Sahara was once a green and hospitable environment for life between 12,000 and 6,000 years ago.
3. During this period, the Sahara was inhabited by diverse populations who hunted, farmed, and fished.
4. The change in climate was caused by the warming of the ocean, which led to increased humidity and rainfall in the Sahara.
5. The warmer ocean evaporated more and created more clouds, leading to monsoons and heavy seasonal rains in the Sahara.
6. The monsoons brought humidity and rain to the Sahara, creating numerous rivers, lakes, and marshy regions.
7. The largest lake, Lake Chad, was formed during this period and could have reached an area 200 times greater than its current size.
8. The lake was connected to the Nile River and allowed aquatic animals to migrate between the two water bodies.
9. The abundance of water and life in the Sahara led to the colonization of the region by flora and fauna.
10. The Sahara was home to giraffes, antelopes, crocodiles, hippos, turtles, fish, and birds.
11. The region was also inhabited by humans, who followed the game and colonized the environment.
12. The human populations in the Sahara developed a culture and way of life adapted to the environment.
13. The "Roundheads" culture appeared in the Sahara around 9,000 years ago and was characterized by the presence of human characters in their paintings.
14. The "Bovidians" culture appeared later and was characterized by the presence of cattle in their paintings.
15. The Bovidians practiced extensive breeding and focused on secondary products such as milk and blood.
16. The populations of the Sahara retained the ability to digest milk in adulthood, a genetic adaptation to their diet.
17. The Bovidians built megaliths, funerary monuments that marked the landscape and indicated ownership of the territory.
18. The Sahara began to dry out again around 4,000 years ago, and the lakes, swamps, and rivers disappeared.
19. The populations of the Sahara adapted to the aridification by digging wells and retreating to the mountain ranges and oases.
20. The introduction of the dromedary from Arabia allowed for the appearance of a large caravan trade across the desert.
21. The Sahara is currently facing desertification and climate change, with the African Union launching the "Great Green Wall" project to stem the advance of the dunes.
22. Some studies suggest that the Sahara may become habitable again due to increased rainfall caused by global warming.