Although cerebral dominance, the specialization of each side of the brain for different functions, was discovered in the 1860s, almost nothing was known for many years about its biological foundations, the study of which has undergone what can only be described as a revolution in the past decade and a half.

Norman Geschwind and Albert Galaburda, two of the leaders of this new field, have assembled a distinguished group of investigators, each a pioneer in some aspect of the biology of dominance. The authors document human brain asymmetry at gross and microscopic levels in both adults and fetuses, its visualization in life by radiological methods, and its manifestation in brain waves. The evolutionary history of brain asymmetry over more than 300,000 years is shown in fossil skulls of humans and apes. In a dramatic reversal of older beliefs, asymmetry of anatomy, function, and chemistry has been demonstrated in many nonhuman species, and experiments have shown the role of hormones and other prenatal influences in the production of asymmetry. The surprising associations of non-right-handedness with twinning and immune disorders are discussed, as well as the asymmetrical malformation of the cortex in childhood dyslexia.

This volume, combining scholarly authority and the excitement of the birth of a new discipline, will be welcomed by those to whom the implications of dominance are becoming evident—neuroscientists, neurologists, linguists, psychologists, experts in learning disorders, speech pathologists—and by specialists in nearly every branch of biology, medicine, and psychology.

Robert Provine boldly goes where other scientists seldom tread—in search of hiccups, coughs, yawns, sneezes, and other lowly, undignified human behaviors. Upon investigation, these instinctive acts bear the imprint of our evolutionary origins and can be uniquely valuable tools for understanding how the human brain works and what makes us different from other species.

Many activities showcased in Curious Behavior are contagious, but none surpasses yawning in this regard—just reading the word can make one succumb. Though we often take it as a sign of sleepiness or boredom, yawning holds clues to the development of our sociality and ability to empathize with others. Its inescapable transmission reminds us that we are sometimes unaware, neurologically programmed beasts of the herd. Other neglected behaviors yield similar revelations. Tickling, we learn, may be the key to programming personhood into robots. Coughing comes in musical, medical, and social varieties. Farting and belching have import for the evolution of human speech. And prenatal behavior is offered as the strangest exhibit of all, defying postnatal logic in every way. Our earthiest acts define Homo sapiens as much as language, bipedalism, tool use, and other more studied characteristics.

As Provine guides us through peculiarities right under our noses, he beckons us to follow with self-experiments: tickling our own feet, keeping a log of when we laugh, and attempting to suppress yawns and sneezes. Such humble investigations provide fodder for grade school science projects as well as doctoral dissertations. Small Science can yield big rewards.