Era beginning/end
In 4280, a significant evolutionary leap of previously non sentient species becoming sentient occurred on Earth due to a clandestine group of human scientists experimenting with the limitations of sentience through biotechnology and genetic manipulation. This era saw the rapid development of advanced societies and cultures among various animal species. Dogs, cats, pigs, and most primates reached intelligence levels comparable to 19th-century humans, while species like cephalopods and cetaceans developed technologies and societies surpassing 21st-century human advancements. Vast underwater cities emerged, and Humans took on the role of guides for these newly advanced societies.