Since the first drawings left on walls of ancient caves, human beings have been fascinated with that unique phenomenon of the animal kingdom, the presence of horns and antlers. From the mythical ''unicorn'' exercising the power over life and death to the perceived aphrodisiacal and other medical properties of rhinoceros horns and growing antlers, these conspicuous protuberances have had a significant place in the history of mankind. Part of that ancient interest in antlers and horns was due to their value as sym bols of masculinity; this interest persists today in trophy hunting, an honorable tradition carried on for centuries in many countries of the world. This book, which deals with evolution, morphology, physiology, and behavior, has not been devised as a comprehensive review of the subject of horns, prong horns, and antlers; rather, it is a series of chapters stimulating thoughts, discus sions, and initiation of new studies. As editors, we did not interfere with the content of articles nor with the opin ions and interpretations of our contributors, and we left them to decide whether to accept the suggestions of our reviewers. Despite the fact that various aspects of cranial appendages have been studied since the end of the eighteenth century, many controversial views still exist, as witnessed in various chapters of this book.

Over the past few decades numerous scientists have called for a unification of the fields of embryo development, genetics, and evolution. Each field has glaring holes in its ability to explain the fundamental phenomena of life. In this book, the author shows how the phenomenon of cell differentiation, considered in its temporal and spatial aspects during embryogenesis, provides a starting point for a unified theory of multicellular organisms (plants, fungi and animals), including their evolution and genetics. This unification is based on the recent discovery of differentiation waves by the author and his colleagues, described in the appendices, and illustrated by a flip movie prepared by a medical artist. To help the reader through the many fields covered, a glossary is included.This book will be of great value to the researcher and practicing doctors/scientists alike. The research students will receive an in-depth tutorial on the topics covered. The seasoned researcher will appreciate the applications and the gold mine of other possibilities for novel research topics.