Alternative biology is a sub-field within speculative evolution and alternative history used to research and speculate if certain aspects of evolutionary history turned out differently. Due to evolutions connection with many other scientific fields, the most common being physics and geography, alternative evolution can encompass a change within Earth's climate, geography, or structure.
One of the most enduring and popular of these speculative fictions is The New Dinosaurs, written by palaeontologist and geologist Dougal Dixon of After Man fame. In it, he speculates a world of dinosaurs without the Cretaceous–Paleogene extinction event taking place.
On the internet, alternative evolution has been able to catch some attention by those who research the field. One of the largest communities focussing on alternative evolution can be found at Speculative Evolution on the subject.