In this forcefully argued book, the leading evolutionary theorist of language draws on evidence from evolutionary biology, genetics, physical anthropology, anatomy, and neuroscience, to provide a framework for studying the evolution of human language and cognition.

Philip Lieberman argues forcibly that the widely influential theories of language's development, advanced by Chomskian linguists and cognitive scientists, especially those that postulate a single dedicated language "module," "organ," or "instinct," are inconsistent with principles and findings of evolutionary biology and neuroscience. He argues that the human neural system in its totality is the basis for the human language ability, for it requires the coordination of neural circuits that regulate motor control with memory and higher cognitive functions. Pointing out that articulate speech is a remarkably efficient means of conveying information, Lieberman also highlights the adaptive significance of the human tongue.

Fully human language involves the species-specific anatomy of speech, together with the neural capacity for thought and movement. In Lieberman's iconoclastic Darwinian view, the human language ability is the confluence of a succession of separate evolutionary developments, jury-rigged by natural selection to work together for an evolutionarily unique ability.

How did we become the linguistic, cultured, and hugely successful apes that we are? Our closest relatives--the other mentally complex and socially skilled primates--offer tantalizing clues. In Tree of Origin nine of the world's top primate experts read these clues and compose the most extensive picture to date of what the behavior of monkeys and apes can tell us about our own evolution as a species.

It has been nearly fifteen years since a single volume addressed the issue of human evolution from a primate perspective, and in that time we have witnessed explosive growth in research on the subject. Tree of Origin gives us the latest news about bonobos, the "make love not war" apes who behave so dramatically unlike chimpanzees. We learn about the tool traditions and social customs that set each ape community apart. We see how DNA analysis is revolutionizing our understanding of paternity, intergroup migration, and reproductive success. And we confront intriguing discoveries about primate hunting behavior, politics, cognition, diet, and the evolution of language and intelligence that challenge claims of human uniqueness in new and subtle ways.

Tree of Origin provides the clearest glimpse yet of the apelike ancestor who left the forest and began the long journey toward modern humanity.