We domesticated the camel
I would like to see a source for this. The research I am aware of says camels were domesticated in southern Arabia from a local stock that did not exist in Africa. They were used to transport incense from Oman to Gaza by 1000 BC, but were not common in the Nile valley until the first century AD.
https://www.sciencedaily.com/releases/2016/05/160509191839.htm
"Burger and her team succeeded in answering this question. The group of researchers analysed up to 7,000-year-old DNA from bones of wild and early-domesticated dromedaries and compared the samples with the genetic profiles of modern dromedary populations from around the world. For the first time, it was possible to identify the Southeast Arabian Peninsula as the region of first domestication. "Our results appear to confirm that the first domestication of wild dromedaries occurred on the southeast coast. This was followed by repeated breeding of wild dromedaries with the early-domesticated populations," Burger explains. The wild ancestor of today's dromedary had a geographically limited range and went extinct around 2,000 years after the first domestication."
The presumption of this study is that camels came late from Egypt, rather than earlier across the Red Sea or Gulf of Aden:
http://www.pnas.org/content/113/24/6707.full
"Genetic distinctiveness of East African dromedaries.
Modern EAF dromedaries exhibit the lowest nuclear (
HE = 0.58,
Ar = 4.48) but the highest mtDNA (
Hd = 0.79, θ
π = 3.62) diversity of all populations (
SI Appendix, Table S1). These elevated values could, in principle, be explained by a large proportion of ancestral diversity in the mtDNA or by a cryptic population structure not accounted for in the analysis (
28). Although 85% of the investigated haplotypes belonged to
HB, dromedaries in Eastern Africa exhibited a more balanced ratio between
HA (38%) and
HB (62%) (
Fig. 1A). These results may be interpreted as the consequence of a random founder effect followed by successive gene flow with a restricted number of sires. Globalization of genetic diversity might not have affected the EAF as much as other populations, likely because of its isolation from the northern part of the continent by eco-geographical obstacles (e.g., the Ethiopian Plateau and the swamps of the Sudd), physiological constraints (humidity, food plants, lack of salt, disease) and, perhaps most importantly, cultural barriers (
SI Appendix, Fig. S4)."