A major synthesis of the latest research on early language acquisition, this book explores what gives infants the remarkable capacity to progress from babbling to meaningful sentences, and what inclines a child to speak. The book examines the neurological, perceptual, social, and linguistic aspects of language acquisition in young children, from prenatal life to full linguistic capacity. To distinguish what comes naturally from what must be taught, the book also considers language in a larger biological context. It examines comparative data on nonhuman primates and songbirds and looks at special human populations, including deaf, blind, autistic, brain damaged, and tracheotomized infants. This biolinguistic approach raises questions about the evolution of linguistic capacity in the species. The 11 chapters of the book are: (1) "A Biolinguistic Approach to Language Development"; (2) "Faces and Voices: A Perceptual Path to Spoken Communication"; (3) "The Social Capacity for Spoken Language"; (4) "Vocal Communication and Vocal Learning"; (5) "The Infant Becomes Articulate"; (6) "The Neural Specialization for Linguistic Communication"; (7) "Development of the Neural Capacity for Linguistic Communication"; (8) "The Urge To Convey and the Capacity for Reference"; (9) "Development of Spoken Language"; (10) "Other Paths: The Neurobiology of Linguistic Variation"; and (11) "Reflections on the Path to Language." Contains over 1,200 references. (ET)