First, black people living in Khartoum now have enough evidence to show that this disaster has changed for a long time. Black people living in Khartoum in the early Stone Age laid most of the foundation of Nile civilization. They even made all kinds of pots and pans before the residents of the world-famous earliest city of Iriha. They live next to a river. During the flood season, the water level of this river is 12 to 30 feet higher than it is now.
These people use javelin heads and barbed spears made of bones. Later, an exquisite harpoon was used with three or four barbs and holes on the handle. Cross the terrible Sahara desert as we know it today, and walk two thousand miles to the west. In some areas of Azovac Valley, you can also find the same thing as this harpoon in the Nile Valley. Even until the third millennium, there were a large number of sexual animals grazing in Lower Nubia.
But now this place is just like Akel said: the conditions in the desert today are really miserable. It is also difficult for the owner who owns a cow-pulling waterwheel to keep one or two animals here all the year round. ?
Second, Hala's withdrawal has become an important obstacle to human traffic. Anyone who travels in this dusty place will notice the traces of the ancient riverbed on the endless battlefield and rock plain in the west of the Nile. These river beds used to bring running water regularly, but now they are as dry as the air over the desert.
The direct reason for this long-term and future existence is unknown. Obviously, this is part of a series of major events that led to the long-term southward movement of the equator, manipulated the advance and retreat of glaciers, and decided the prehistoric rainstorm.
In any case, the important point is that about 5,000 or 6,000 years ago, blacks began to migrate and reproduce, and before and after North Africa started to settle agriculture, the Sahara became an important obstacle to human transportation.
Due to the extension of the Sahara, it has become an obstacle to human contact between the North and the South, and it has also greatly affected the process of human development needs in Africa.
In the north of this deteriorating desert, all developed societies and civilizations in North Africa, the Middle East and the Mediterranean have frequent and rarely interrupted links.
Third, the connection between North and South Africa is on the continent south of the desert, and sometimes the population flows freely. Therefore, blacks can be seen almost everywhere today. But the south and the north are increasingly separated. They go their separate ways, and each has its own development. But this is just a general statement, which inevitably has its limitations.
In fact, the connection between North and South has never been completely cut off.
From Fizan to the Niger River, or along the red coast to the east of the Horn of Africa, there are routes of plunder, trade and migration. Carthage once traded along the west coast, although the Phoenicians were too mysterious to know their size or how far they would go.
In the centuries after about 1200 BC, horses and vehicles were very common things in the Sahara, and then there were camels. But the road across the desert is difficult to confirm, long and dangerous. Even if the Arabs in the Middle Ages rode cattle across the Sahara desert along one fixed well after another, it would take two months, and many people never reached their destination after they set off.
Of course, this does not mean that without the drought in the Sahara, the human society on the African continent will develop according to the Mediterranean type. This vast and changeable continent will always develop irregularly and unevenly under any circumstances. Some ethnic groups are developing faster than others. Because the natural conditions in this place may be forests or plains, which are suitable for healthy highlands and swamps where malaria is prevalent, some places are rich in plant species, while others are extremely scarce, which often leads to various irregular and unique development types.
However, the drought in the Sahara Desert has played an equally important role in history. In the north of the desert, the civilizations of Crescent Waal can freely communicate with each other, accumulating one invention after another, and one competitor after another brings new pressure to them and their neighbors.
In this way, after centuries, they all entered the glorious bronze age of religion-dominated politics from the initial primitive state. This boiling life in the north was only a faint and puzzling echo to the nationalities in the southern marginal areas at that time. When the echo disappears, the influence will be far away.
4. Early civilizations all originated from the study of river basins. Why early civilizations appeared in the Nile Valley, the Near East and Mesopotamia, but not in northern Europe or South Africa, this question can only be an interesting fantasy topic according to the current level of knowledge.
Cultivated land in the big river basin seems to be the key to the problem. Early civilizations originated from large river basins, and no matter how different they are, they all have the characteristics of natural irrigation and soil renewal.
These rivers provide new and very fertile soil for agriculture every year. Let nomads find a way to grow food far better than simply gathering and hunting, and get rid of nomadic life.
After living in the same place like this for several years, a series of technical problems of formal farming appeared. Working on this? ? Where exactly does the river provide new soil every year? When there is a problem, there is a problem of overproduction of grain.
After the unheard-of phenomenon of surplus grain, a commercial basis appeared. In turn, trade becomes the basis of permanent settlement, which means specialization, division of labor and urban development. The development of cities means the development of civilization and the central government. Just like Egypt and other ancient civilizations in the Bronze Age, rule is unique, autocratic and often theocracy.
So there are some situations, and calculation becomes necessary, even if it is only limited to calculating the materials piled up by Pharaoh's priests in warehouses and warehouses. It was these early calculation methods that later developed into writing methods.
Archaeologists have recorded many facts about this complex and spontaneous development process in revolutionary discoveries in the past few years. If there is any doubt about the exact development process, the basic nature of this process has been accepted.
5. South of the desert, the place where world civilization is isolated from the world is south of the desert, which is different from most civilizations in the ancient world. There seems to be no settlement in the river basin that once played a decisive role in the Middle East, Indian and China. Not only that, because the land there is so vast, there is no case of overproduction of food in a certain place.
After capturing the local wild animals, ancient people moved to other places. Even later, when the technology of agriculture and metal age made the population density of a certain area exceed the supply capacity of local land, the same was true. Tribal branches broke away from the original tribe and moved to new areas.
They often move to undeveloped land. Sometimes there will be conflicts with some earlier immigrants or tour groups, so the process of migration will happen again until this new wave and fluctuation of migration passes through forests and plains and slowly disappears. In contrast to this simple picture, there are some major and obvious exceptions. But this scene is worth remembering, because it helps to explain the lifestyle and motivation of African residents in history.
Now, we know the history of many tribes, which often includes the history of migration and resettlement. They often talk about the movement from north to east, and the general migration route is likely to be from north to south. In this way, in the south of the desert, there are no mountains and endless deserts across the continent, and an endless and accelerating migration map appears. Even in the dense forests around the Congo basin, such unknown tribes have infiltrated. They are like dim stars, sometimes heading south, sometimes heading west, and then turning back as time goes by, moving east and north along our uncertain secret trajectory.