>>44270
Well the growth rate is higher in Libya than in Algeria, but the latter had larger population base. So it's historical reasons - beside the amount of habitable areas. I kinda recall from history lessons in relation to ancient Egypt, that west from there was very sparsely populated. But considering the suitability of Egypt due to the Nile, it doesn't mean much.
In Rome all three places (Egypt, "Africa", and Mauritania) was used as a source of grain.