It's the realistic future where everyone in the world is black. See also: global demographic prognosis like here: https://ec.europa.eu/eurostat/statistics-explained/images/thumb/2/2c/Population_index_%281960%3D100%29.png/700px-Population_index_%281960%3D100%29.png (and remember "Europe" here doesn't mean white, and "World" includes Africa). The UN for example estimates that already by 2100 most of the children in the entire world will be born in the Sub-Saharan Africa (where the total population was less than 100 million just 100 years ago). Their graphs also don't predict any kind of slowing of the population growth there, at all, ever.