Galapagos by Kurt Vonnegut is a book told from the point of view of a ghost looking back at the world a million years before.
Galapagos, as a whole, describes the plight of a group of humans from various parts of the world getting stranded on the Galapagos Islands after their ship is wrecked. This happens mostly due to a global financial crisis that destroys the economies of many countries. Afterwards, a disease sterilizes all humans on earth expect for the group of humans stranded on the Galapagos Islands. The narrator, a ghost named Leon Trout, is forced to watch their evolution for the next million years because he refused to travel down the blue tunnel to the afterlife.
Leon Trout is a veteran of the Vietnam War and settled in Sweden after going AWOL. There, he worked on the construction of the ship, the Bahia de Darwin. This ship is used for a cruise that garnered international attention as the "Nature Cruise of the Century". However, as the financial crisis loomed on the horizon, reservations to the cruise were canceled until there were only 6 people. The ship still sets sail, but only after being fully looted by hungry locals and thought to be destroyed by the Peruvian Air Force (they missed).
After the mankind outside of the Galapagos Islands is fully destroyed, Leon gets to observe the slow evolution of the remaining humans into aquatic mammals. The first step is when a Japanese baby is born covered in fur. Throughout the story, Trout continues to enforce his claim that everything bad in the world was caused by "the oversized human brain". In support of his claim, natural selection decides that a streamlined head is better for swimming and decreases the size of the human brain.
