The goals of this volume are twofold. First, it aims to provide a novel focus on adaptive explanations for cranial and postcranial features and functional complexes, socioecological systems, life history patterns, etc. in early primates. Second, it aims to offer a detailed rendering of the phylogenetic affinities of such basal taxa to later primate clades as well as to other early/recent mammalian orders. Thus, in addition to the strictly paleontological or systemic questions regarding Primate Origins, the editors plan to concentrate on the adaptive significance of primate characteristics. These questions are best approached through both paleontological and neontological comparative research on a variety of primate and non-primate materials. The volume is timely because it capitalizes on an increasing and important degree of novel independent museum, field and laboratory based research on many of the important outstanding issues regarding primate origins. Furthermore, by intergrating such a disparate sources of experimental, comparative, paleontological, ecological and molecular information into a single edited volume, it provides the broadest possible perspective on early primate phylogeny and the adaptive uniqueness of the Order Primates.