How would you describe the diffusion of civilizations in Africa and the Near East?

The high antiquity of civilization in the Middle East is largely due to the existence of convenient land bridges and easy sea lanes passable in summer or winter, in dry or wet seasons. Movement of large numbers of people north of the Caspian Sea was virtually impossible in winter, owing to the severity of the climate; central Eurasia was often too dry in summer. Land passage between Asia and Africa was in early times limited to narrow strips of land in the Isthmus of Suez. Large-scale desert travel was limited to special routes in Iran and in North Africa, both east and west of the Nile Valley.

Cherokee  removal, part of the trail of tears, refers to the  forced  relocation between 1836 and 1839 of thecherokee  nation from  their lands ingeorgia, south carolina, north carolina, tennessee, texas, and alabama to the indian territory (present day oklahoma)  in  the thenwestern united states, and the resultant deaths