I recall reading a science fiction short story in the late 1970s about how the human brain evolves. The cells in the brain become more and more specialized as time goes by. Eventually the human brain is reduced to a single cell with evolution having come full circle back to a single-celled organism.
I thought the novel was a Hugo or Nebula Award winner but I may be mistaken. What is the title of the story and who wrote it?
The Man Who Evolved, Edmond Hamilton, first published in the April 1931 issue of Wonder Stories?
Pollard has built himself a cosmic-ray-concentrator that will allow him to evolve at the rate of 50 million years every 15 minutes exposure, but he needs someone else to operate it, which is why he has invited Wright and Dutton to his laboratory. Wright reluctantly agrees to operate Pollard's device.
Fifteen minutes in the device leave Pollard with enhanced intelligence and a highly developed physique. However, he is eager to continue the process and explore the further evolutionary changes mankind will undergo. The next stage, though, finds him with a huge bald head atop a frail body and atrophied emotions. He insists on continuing, and each stage of the process finds his brain larger and more powerful, and his body smaller and weaker. At each stage Pollard derides the previous stage as brutish and primitive, praises his current condition and looks forward to the next stage in his evolution.
After the third transformation, Pollard's ambition is to enslave humanity and turn the Earth into a vast laboratory for his own use, but as the transformations proceed he moves beyond such desires, with only intellectual curiosity remaining. The penultimate stage finds Pollard transformed into a vast, naked, telepathic brain that feeds on pure energy. A final use of the device, to Wright's shock, leaves Pollard a pool of protoplasm, apparently bringing the evolution of humanity full circle back to its beginning.
Complete text here.
