Why are the borders of Egypt, Libya and Sudan divided by latitude and longitude?

In fact, you will find that the borders of most countries in the world are bounded by natural objects such as mountains and rivers.

To divide borders, but most African countries are divided by latitude.

The reason is that nationality and geographical environment are integrated. For example, Mongolia is a nation living in deserts and grasslands.

If there is a mountain range that blocks water vapor, with grasslands in the north and forests in the south, it is likely to be built.

That is, the embryonic form of a national border, because people on both sides of the mountain range have different lifestyles and have little communication.

Different cultures will be formed, and finally a national border will be determined through war or negotiation based on this mountain range.

Therefore, under normal circumstances, all national boundaries should be natural objects.

But Africa is abnormal because almost all countries in Africa have been in it for a long time.

They have all become colonies of western European powers, and colonists don't care about any nationality or nationality.

They are profit-oriented and try their best to expand their land to the maximum, which is simply enclosure.

In case of dispute, divide it by geometric method and calculate the latitude and longitude.

Sometimes they even directly define their sphere of influence as their colonial boundaries. When Africa became independent,

Independence is achieved in the form of colonial independence, so this abnormal way of dividing national boundaries

I stayed.