| Abstract: |
Although the diminutive <i>Homo floresiensis</i> has been known for a decade, its phylogenetic status remains highly contentious. A broad range of potential explanations for the evolution of this species has been explored. One view is that <i>H. floresiensis</i> is derived from Asian <i>Homo erectus</i> that arrived on Flores and subsequently evolved a smaller body size, perhaps to survive the constrained resources they faced in a new island environment. Fossil remains of <i>H. erectus,</i> well known from Java, have not yet been discovered on Flores. The second hypothesis is that <i>H. floresiensis</i> is directly descended from an early <i>Homo lineage</i> with roots in Africa, such as <i>Homo habilis
</i> the third is that it is <i>Homo sapiens</i> with pathology. We use parsimony and Bayesian phylogenetic methods to test these hypotheses. Our phylogenetic data build upon those characters previously presented in support of these hypotheses by broadening the range of traits to include the crania, mandibles, dentition, and postcrania of <i>Homo</i> and <i>Australopithecus.</i> The new data and analyses support the hypothesis that <i>H. floresiensis</i> is an early <i>Homo</i> lineage: <i>H. floresiensis</i> is sister either to <i>H. habilis</i> alone or to a clade consisting of at least <i>H. habilis, H. erectus, Homo ergaster,</i> and <i>H. sapiens.</i> A close phylogenetic relationship between <i>H. floresiensis</i> and <i>H. erectus</i> or <i>H. sapiens</i> can be rejected
furthermore, most of the traits separating <i>H. floresiensis</i> from <i>H. sapiens</i> are not readily attributable to pathology (e.g., Down syndrome). The results suggest <i>H. floresiensis</i> is a long-surviving relict of an early (>1.75 Ma) hominin lineage and a hitherto unknown migration out of Africa, and not a recent derivative of either <i>H. erectus</i> or <i>H. sapiens.</i>
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