Darwin's Nightmare
The larger scope of the story explores the gun trade to Africa that takes place under the covers -- Russian pilots fly guns into Africa, then fly fish back out to Europe. The hazards and consequences of this trade are explored, including the pan-African violence propagated by constant flow of weapons into the continent.
If it is a "survival of the fittest" world, as Darwin concluded, then the capitalist interests that fund the gun runners are climbing the evolutionary ladder on the backs of the Africans in this stark Darwinian example.
Much like the foreseeable extinction of the Lake Victoria perch, and death of Lake Victoria itself, the Africans are in grave jeopardy, even as they survive in the only ways they know how.