If it weren't for flooding, the soil near the river would not be as fertile as it was thanks to the Nile River flooding. Thus, people who lived near the river wouldn't be able to farm as effectively as before which would affect their economy and rate of survival quite drastically. For growth and development of a community, it is important that the soil be fertile, which usually happens when a river floods.
The enormous amount of ethnicities and languages in the countries of Sahara contributed to mainly bad and unwanted things to be happening. In lots of the countries there's big devidence between the ethnic groups and it is not unusual that they have clashes that very often have devastating consequences. The countries of the southern half of Sahara usually have clashes on daily basis and there's open hatred and violence between the different ethnic groups, which also leads to the governments having enormous difficulties in the control of some regions. In the northern half of Sahara there has been a systematic genocide going on for quite some time that is kept behind the curtains, like the example with the Barbers and the Jews of North Africa whose numbers have been significantly falling down and they have been massacred systematically by other groups.
I think that the answer is: The colonies developed an ability for self governing
Answer: Passed on September 18, 1850 by Congress, The Fugitive Slave Act of 1850 was part of the Compromise of 1850. The act required that slaves be returned to their owners, even if they were in a free state. The act also made the federal government responsible for finding, returning, and trying escaped slaves