From tvtropes:
Evolution isn’t goal-directed. Sometimes …a species (often but not limited to humanity) will sometimes evolve into a more feral, less civilized, sometimes even non-sapient variety, regaining “primitive” characteristics. These “primitive” characteristics can include behaviors and/or physical traits…
Most basic is the scenario common to Post-Apocalyptic settings After the End, where humanity (or another species) is still physiologically more or less the same, but society has collapsed and technological and cultural regression have set in… In more extreme scenarios, the population may have evolved into a new subspecies or another species altogether… Most Scavenger World-type future settings are not far enough removed from the Present Day for natural selection to favor such drastic changes.
May overlap with Was Once a Man. Sometimes, it’s the motivation of an Evilutionary Biologist to try and take control of evolution in order to avert this fate.
Common to After the End settings. Likely to exist in Humanity’s Wake. Contrast Evolutionary Levels, Ultimate Lifeform and The Singularity (all of which tend to assume evolution’s a linear, goal driven process). Has nothing to do with the effects of a Devolution Device.
This trope has been on my mind as I write Edenfall, the sequel to Genesis Earth. In that book, this trope featured prominently, and drove the main character to question his faith in the progression of the natural world from chaos to order, entropy to complexity, and ignorance and barbarity to knowledge and civilization.
Perhaps the most prominent example of this trope is the Morlocks and Eloi from H.G. Wells’s The Time Machine. In the far future, the children of the rich elites of society have evolved into dainty, helpless, childlike creatures, while the descendants of the lower classes have evolved into dark and predatory monsters. As different as they are, though, they have both lost the drive and ingenuity that makes us human: the Eloi because it was pamperd out of them, and the Morlocks because they were repressed for so long. Both of them have lost their humanity and devolved into little more than animals.
In the Victorian era, people generally had faith in the slow and steady march of progress: that ignorance and superstition inevitably gave way to the light of science and reason, each successive age tended to be more advanced and scientific that the previous ages, and that humanity represented the pinnacle of evolution, the crowning achievement of the natural world. They rejected the notion that catastrophic and violent upheavals had any significant effect on the development of cilivization or humanity, and believed that the world was in a state of constant, unstoppable improvement.
Well, the two worlds wars pretty much shattered that notion forever. And since that time, we’ve discovered all sorts of evidence that in history and evolution, catastrophic change and violent upheaval are the rule, rather than the exception. From the bronze age collapse and the black death to supernovae and the extinction of the dinosaurs, the Victorian concept of the slow, steady, and inevitable march of progress looks very quaint indeed.
That was what I wanted to deconstruct in Genesis Earth. But now that I’m writing the sequels, I plan to subvert this trope. I can’t say how without giving spoilers, but it’s going to be a major plot point, especially in the third book.
What happens when humans meddle in evolution? When we hack into our genetic code and rewrite our place in the natural order? Can time heal the scars of our broken world, or will it take something else to fix us? Something more than human, or something so fundamental to our humanity that it lies in every heart?
Anyways, those are the things on my mind as I finish up Edenfall and get ready to write The Stars of Redemption. With luck, they will both be out by the end of this year!