The Vision Revolution

Primates are set apart from most mammals in their greater reliance on vision and a correspondingly reduced sense of smell. This trait is so extreme in humans that nearly half of our oversized brains are dedicated to processing visual information. As Mark Changizi explains in the introduction to The Vision Revolution, the visual system is perhaps the best-understood part of the human brain — but, while researchers have mapped out how, few have provided satisfactory explanations for why we see the world the way we do. As a theoretical neuroscientist, Changizi focuses on why humans have evolved such visual “superpowers” as color vision and binocularity. His answers are surprising, overturning theories that have dominated primatology since the 1970s. For example, Changizi argues that (despite what many textbooks say) color vision did not evolve to help our arboreal ancestors locate fruit in the jungle canopy but rather to help them read the social cues found in subtle changes in skin tone. (Or not so subtle, if you think of a baboon’s behind.) Readers, however, need not be well versed in academic debates to enjoy Changizi’s lucid explanations. Filled with optical illusions and simple experiments for the reader to perform, this book may be the most fun you’ll have learning about human cognition and evolution.