For the first time in the four years that FORBES has been tracking Africa’s richest, Nigeria bests South Africa. At the top yet again is cement tycoon Aliko Dangote of Nigeria, joined on the list of Africa’s 50 Richest by 12 other countrymen. In comparison South Africa claims 11 spots, down from 14 a year ago. Nigeria is showing its strength, having earned commendations for its efforts to snuff out Ebola in the country, which Dangote helped fund — and despite a recent drop in oil prices. There are four new billionaires on the list: Orji Uzor Kalu of Nigeria, Tony Elumelu of Nigeria, Theophilus Danjuma of Nigeria and King Mohammed VI of Morocco. That brings the number of billionaires on the list to 28, up one from 27 last year. Three billionaires on last year’s list are no longer members of the 10-figure club: Vimal Shah of Kenya is off the list, replaced by his father Bhimji Depar Shah at a lower net worth. Abdulsamad Rabiu of Nigeria dropped below...