Last and First Men

Last and First Men: A Story of the Near and Far Future is a 1930 science fiction novel by Olaf Stapledon, featuring a small amount of prehistoric content. In 1932 a sequel, Last Men in London was released.

Plot
The novel follows the future evolution of humanity, from Homo Sapiens as the "first men", through 18 species and across several planets, to the extinction of humanity on Neptune. The story is told from a distant and abstract point of view, with little dialogue and few individual characters.

Prehistoric Content
While most of the novel involves technological civilizations, several segments involve species and societies with little technology.

Two brief segments relate how the first men suffered massive collapse after creating technological civilizations, and were reduced to extremely primitive states. The second of these states led to the speciation of the first men into the second men in Eurasia, and "subhumans" in North America.

The second men encountered these "subhumans" as they explored the world, who are described as using their arms to move, flat-headed, baboon-like, and afflicted with diseases that cause terrible odors and physical debilitation, but which increased their attractiveness to others. This species had also been partially domesticated by a newly evolved species of intelligent monkey which ruled the subhumans by the use of special oils whose scent frightened them. The monkeys were intelligent enough to create an arboreal city and used poison arrows, as well as hoarding precious metals. The avaricious nature of the monkeys led them to conflict with the peaceful and empathetic second men, who hated the slavery the subhumans had been forced into. The monkeys eventually destroyed the civilization of the second men by spreading the plagues of the subhumans among them, but their growing obsession with metal led to them weighing themselves down and becoming less mentally agile, and the subhumans eventually rebelled and ate their masters.

Later in the history of the second men, the history of life on the planet Mars is described. Multicellular life originated in a manner similar to Earth, but with generally less water and lower gravity and atmospheric pressure. A variety of life forms evolved, including a species of huge "spidery" creatures similar to crustaceans or grasshopper, who dominated their environments in a similar as early humans did, but evolving millions of years earlier. Loss of water and atmosphere from Mars, however, led to the decline of multicellular organisms, and the rise of a type of "subvital" particle, smaller than a terrestrial virus, capable of surviving in extremely dry and even airless conditions. These subvital units were also capable of perceiving and creating "aetherial" vibrations undetectable by larger organisms. These vibrations gave the particles an ability of almost telepathic communication with other physically distant particles. Being subcellular organisms, these Martians did not have any individual intelligence, but as large intercommunicating clouds they were capable of collective action, though, and organization of specialized particles to create organs such as eyes or to transport water. These Martian clouds were able to split, merge, and individual particles could even survive on their own. Because of this, the Martians, even when split into separate clouds, did not have any concept of individuality. Their diffuse nature and the difficulty of achieving solidity led them to worship the quality of extreme solidity, expressed by excavating the few Martian diamonds and placing them in special mountain-top shrines. The intelligence of the Martians allowed them to adapt to the extreme hostility of the declining Martian environment, but eventually they were forced to invade Earth for its water. The Martians considered telepathic wave emission as the criterion of intelligence, and did not recognize the second men as the masters of their technological civilization, but rather their radio-wave emitting machines. Incomprehension between the Martians and second men led to thousands of years of conflict. The second men were eventually able to defeat the Martians, but at the cost of destroying their own civilization.

The early history of the third men, who had a vastly different mentality than the first and second men is described, including how even in a very primitive state, the third achieved great feats of hunting and domestication, including selective breeding.

The fifth, an artificial species with a high level of technology, preserved a whole continent in a primeval state, where individuals would vacation for years at a time to maintain contact with humanity's primitive origins, living without any tools or technology they could not create themselves, mostly flint and bone, sustaining themselves with hunting and agriculture. Powerful predators roamed this Wild Continent and there was a considerable death rate of people who lived there.

After traveling to Venus and destroying the native intelligent species, aquatic beings who used radioactive materials gathered in infancy to provide their energy, the fifth men again returned to a primitive state. There evolved a seal-like species of human, whose intelligence led them to dominate the oceans as apex predators, and a more humanoid form. These sixth men eventually created a technological civilization and designed the flying seventh men, who lost their knowledge of science and technology due to their generally detached beatific nature. An epidemic of non-flying births eventually led to the re-emergence of civilization and the end of the flying men.

Venus was eventually abandoned due to changes in the Sun's state, and the ninth men were created to live on Neptune. They were unable to efficiently survive there, and lost their intelligence while splitting into many species. These achieved a great diversity of animal forms, including sheep-like and rabbit-like ruminant grazers, cat-like carnivores, seal and porpoise-like aquatic forms, and even fliers the size of hummingbirds. Some of these creatures still had echoes of humanity's intelligence in them, but extremely faded and incoherent. After three hundred million years on Neptune, a rabbit-like human descendant re-evolved articulate fingers from the extensions of its knuckles, and a new organization of the brain rather than a re-emergence of the human neocortex. This species spread throughout the Neptunian continents, but eventually declined, giving rise to several others. The 11th through 13th men are quickly described, being respectively, "crouched and tusked", "long of muzzle and large of base, habitually squatted on its haunches like the kangaroo", and "erect, but literally almost as broad as they were tall, and bloody-minded". Thereafter the 14th through 18th species of humanity had a high level of civilization.

The 18th men had the highest level of technology ever achieved by humanity, and also maintained a wild continent like the fifth men. They called it the Land of the Young, as members of the species would travel there on reaching adolescence and remain for a thousand years, living without the aid of technology, developing their own tribes and myths, and even warring with each other, without the interference of the adults of their species.