Brain Wave
Poul Anderson
 At the end of the Cretaceous period the Earth moved into an energy dampening field in space. As long as Earth was in this field all conductors became more insulating. As a result almost all of the life on Earth with neurons died off, causing the Cretaceous–Paleogene extinction event. The ones that survived passed on their genes for sufficiently capable neurons to deal with the new circumstance. Now in modern times the Earth suddenly moves out of the field. Within weeks all animal life on earth becomes about 5 times as intelligent. The novel goes through the triumphs and tribulations of various people and non-human animals and groups on earth after this event. The book opens with a lyrical description of a rabbit stuck inside of a trap becoming able to reason his way out. This is a common theme in the book. Animal traps are based on the idea that the animal cannot reason their way out of them. When the animals get the ability to reason they start escaping. Institutions which seemed to be vital to human society, such as a money economy and centralized government, disappear in North America, while Africans, with the assistance of chimpanzees, overcome colonial rule and Chinese rebel against the Communist government. However, some of the means by which people cope with the "Change" are inventing new anti-scientific religions such as the Third Ba'al or adopting pseudo-science. As humans develop interstellar travel, they discover no other races are as intelligent as they; other races developed pre-Change intelligence, and there was no environmental pressure to select for higher intellgience after that.