From ear to ear and including everything in between, a comprehensive, occasionally disproportionate, look at all things related to the human face. Core signifier of our selves, indicator of all emotions, center of four of our five senses, the human face is the fine-tuned product of relentless natural selection, says McNeill. The slight ridges on our ears, for example, help us locate the direction of sounds. Tears oxygenate the eyes where blood vessels would hinder vision. The nose helps make us better swimmers, and thus, according to one theory, carried our ancestors through a difficult evolutionary period when much of their time was spent in the water hiding from predators. Though facial characteristics may differ among the races, often for reasons related to climate (long noses are an advantage in a warm, dry climate, lighter skin can mote easily synthesize vitamin D from weak sunlight, and so on), there is a remarkable universality to both our expressions and out notions of beauty. A smile or a frown have the same meaning across every single human culture. Similarly, a great beauty in Afghanistan will still be beautiful in Zimbabwe. The theory behind this universality holds that beauty is largely a function of symmetry--the more symmetrical, the more attractive. Symmetry in turn reflects healthy genes and thus indicates good reproductive possibilities. McNeill (coauthor with Paul Freiberger of Fuzzy Logic, 1993) does a good job of welding his disparate mix of history, physiology, biology, and sociology into an engaging, digression-rich narrative. It's a notable achievement, though some judicious nipping and tucking would have helped finesse the general pacing (an excursus on theories of humor seems particularly unnecessary). But McNeill's thoroughness, wide-ranging research, and deft touch make for an engaging and revealing tale.