The Sheltering Desert, by Henno Martin, is about how two men, Henno and his friend Hermann Korn, decided that they wanted nothing at all to do with World War II, and in 1940 went to live in a remote desert part of Namibia until, they hoped, hostilities ended.
They had gone to what was then South West Africa in 1935 to do geological research on the Naukluft, and by 1940 were threatened with Internment. They were completely against the madness of the War, and decided to live and survive like Bushmen in the Kuiseb River canyon. This is a very harsh part of the world, where there is little water and the temperature rises in summer.
The story was made into a movie in 1991, and you may be able to find it on Youtube. The movie diverges considerably from the book, in that it spends quite a bit of time setting the scene in 1940s South West Africa, and also seems to overemphasize the search, by the authorities, for the two men, but it’s a watchable film and the scenery is wonderful.
Because the terrain was so harsh in the Kuiseb River gorge area, and at times the wild game and water ran out, they found it difficult to survive. They lived off what they could shoot with their pistol and fish that they found in some pools. After a year, they found themselves getting philosophical, and had discussions between themselves about whether evolution was purely mechanically determined by the interplay of hereditary and environment. Their conclusion was that animals with specialisations were less likely to evolve, and that man had evolved particularly because of a lack of specialisation.
The Namib sounds like an interesting part of the world. It was inhabited by scattered Khoikhoi for thousands of years, and Martin and Korn found numerous stone tools near their various camps.