Speculative Evolution

Speculative evolution is a subgenre of science fiction and an artistic movement centered on hypothetical scenarios in the evolution of life, and it is a significant form of fictional biology. It is also known as speculative biology, and as speculative zoology when it concerns hypothetical animals. Works in the subgenre may invent entirely fictional species evolving on a world other than Earth, or may take the form of alternate history built around an alternate path for the evolution of life on Earth. Because of its close connection to and grounding in real biology, speculative evolution is often considered a form of hard science fiction. The modern speculative evolution movement is generally traced to Dougal Dixon's 1981 book After Man, which imagined a complete future Earth ecosystem populated by more than a hundred hypothetical animals, and which was followed by several further books exploring other alternate and future scenarios.