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Rhinos are known from North America and the Old World, and have a well-documented fossil record. Rhinocerotidae is first reported from the Eocene, and members of the family persisted through the remaining Cenozoic. This chapter examines fossil remains of two Rhinocerotidae representatives present in the Daka Member. Specimens of Ceratotherium simum, a grazer, include a mandible, a maxilla, and several dental specimens. Daka Member Diceros is represented by a single premolar.

This chapter examines specimen samples of micromammals and birds preserved in the Daka Member. One fossil from the Daka Member does not belong to any of the previously described taxa from the Pleistocene of Ethiopia. It is possibly a taxon within Order Ciconiiformes, which is composed of large wading birds, including herons, egrets, and storks. Two other specimens are identified, a cranium of the murid Arvicanthis, the unstriped grass mouse or grass rat, and a preserved cranium from the catfish order, Siluriformes.

This chapter discusses Daka hominid material, and presents a detailed ectocranial description of the Daka calvaria (BOU-VP-2/66) and other cranial and mandibular specimens from the Daka Member. It presents a detailed comparative description, tomographic analysis, and systematic interpretation of the cranium. The chapter also presents the postcranial elements in depth, discussing the functional and systematic information they provide. The most important conclusion that can be drawn from the comparison of Daka Homo erectus calvaria to other cranial specimens referred to Homo erectus is that ectocranial features were distributed in a complex mosaic across the Pleistocene within Africa and Eurasia.

This book describes the importance of the Dakanihylo (Daka) Member of the Bouri Formation in the Afir Rift to African Pleistocene studies. The Daka Member has preserved a very rich array of fossil mammals (750 collected specimens), including several Homo erectus specimens. The richness, stratigraphic integrity, and temporal placement of Ethiopia's Daka Member make it key to exploring the development of the Afar Rift, African Pleistocene fauna, and our own evolution. The book presents detailed descriptions and interpretations of the hominids and the non-hominid fauna collected in the Daka Member, provides background information on stratigraphy and methodology necessary to understand these interpretations, and summarizes the overall importance of this material in the context of African Pleistocene paleontology.

This chapter focuses on the Daka Member volcanic and sedimentary stratigraphic units. It also discusses the chronostratigraphic and lithostratigraphic characteristics, geographic distributions, geomorphic features, and the paleontological and archaeological records of the underlying Hata and overlying Herto Members.

This chapter examines the carnivore fossils present in the Daka Member. Carnivores from the Daka Member include leopards, lions, and crocutoid hyaenas. There are 10 specimens of carnivore fossils in the Daka Member, and the assemblage presents one of the best Pleistocene Crocuta crania known. This cranium, along with remains of both Panthera cf. leo and Panthera cf. pardus, indicate the presence of numerous large carnivores in the community represented by the Daka Member.

The Daka Member presents a large sample of equids. This chapter discusses fossil records of Equidae, represented by the hipparionine genus Eurygnathohippus and Equus in the Daka Member. The two taxa are very abundant, together representing approximately 20 percent of the Daka Member large mammal assemblage in terms of number of specimens. Remains include mandibular, dental, and postcranial specimens. In addition, two partial crania of Equus have been recovered (BOU-VP-3/54 and BOU-VP-25/94), but neither are well-enough preserved to allow for a detailed metric analysis.

The Daka Member is very rich in elephant fossils. Cranial remains of Elephas recki recki were excavated from there during the 1999 and 2002 field seasons. Elephas (Palaeoloxodon) recki is one of the most common faunal elements of the Plio-Pleistocene of eastern Africa. Cranial materials of Elephas recki excavated from the Daka Member are incomplete, and they differ in their preserved portions. The developmental age also differs from specimen to specimen. The cranial features show a number of characters new to eastern African fossil elephants, but their molar features, specifically high hypsodonty and strongly folded enamel, are closely comparable with those of advanced Elephas recki from Olduvai Gorge. These findings shed new light on emigration of palaeoloxodonts from Africa to Eurasia, as well as the taxonomy and spatiotemporal distribution of the Eurasian palaeoloxodont species.

This chapter discusses the tomographic analysis of the Daka calvaria. It presents observations made on distortion, subcortical structures, and endocranial features through the use of computed tomographic (CT) imagery of the Daka calvaria. The chapter provides descriptions of individual cranial vaults bones and of the endocast, and presents cranial metrics and vault thicknesses, which were derived from micro-CT data.

This chapter examines the postcranial remains of hominids from the Daka Member. The sample comprises three femora, one tibia, and one talus. The tibia and femora are presented with descriptions of their preservation and anatomy relative to comparative specimens. Specific femoral features are discussed with respect to their occurrence in the Daka femora, in other early Pleistocene Homo specimens, and in a sample of femora from a robust modern human population. The talus is only briefly presented, as it was discovered in late 2005 and has not yet been cleaned for detailed study. The chapter compares Daka Member postcrania to a set of specimens from the early and middle Pleistocene that have been assigned to early Homo or Homo erectus.

Geographic distributions of fossilized and recent taxa can be used to illuminate prehistoric connections between geographic regions. This chapter discusses the geographic distribution and ecological niche of the Daka Member vertebrate taxa. Some Daka taxa are restricted to, but widespread within, sub-Saharan Africa during the Pliocene and Pleistocene: Aepyceros, Megalotragus, Numidocapra, Antidorcas, Syncerus, and Colobinae. Bouria and Nitidarcus are known only from the Daka Member and are endemic exclusively to the Daka Member and eastern Africa.

This concluding chapter summarizes the contributions of earlier chapters in this book and discusses the relevance of the Daka Member to broader questions of paleoclimate and evolution. It outlines the impacts that Daka fossils have had on the different taxonomic groups and also considers some recent attempts to relate biotic evolution to paleoclimate.