Most of the cultural divides that took place in norther Africa due to the geography had to do with proximity to the water, with the tribes closer to the water more likely to be disturbed by colonists.
<span>The one topical reason for the plague portrayed by ibn khaldun which visited eurasia between the time period of 1331 and 1347 is that the rats, bugs, microbes, military clash in Caffa, as well as financial exchange or economic trade interfaces between Afro-Eurasia.
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1. this answer is correct. hope this helps :)
