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Tubulidentata is currently represented by a single extant species—Orycteropus afer, the aardvark. They are the largest African anteaters. This chapter focuses on the identification and description of these aardvark specimens found in the Middle Awash late Miocene. Their importance for improving our knowledge of the order Tubulidentata is also discussed.

Priongale breviceps is a very small mammal with carnivorous adaptations described by Schmidt-Kittler and Heizmann (1991) on the basis of fragmentary craniodental material from a number of early Miocene localities in Kenya and Uganda. The dental homologies as reconstructed are unique among mammals, and therefore the taxon is placed in Mammalia incerta sedis. It has recently been accompanied in the family Prionogalidae by Namasector soriae, from Namibia and the family was suggested to belong in the Creodonta. This chapter describes the systematic paleontology of Prionogalidae (Mammalia incertae sedis).

40Ar/39Ar dating has been applied extensively to volcanic units of late Miocene to Pleistocene age in the Middle Awash study area, and is the most important dating method applied to these deposits. This chapter discusses all available 40Ar/39Ar data for the Adu-Asa Formation, including some data not previously reported, plus some previously unpublished results from the nearby Central Awash Complex (CAC). The methods and facilities employed for 40Ar/39Ar dating is divided into two different approaches: incremental heating and single-crystal total fusion.

This chapter focuses on the pronghorn antelopes in North America during the prehistoric period. The fossil record of antilocaprids in North America extends back into the Miocene with forms characterized by forked permanent horns, but it not clear whether they had horn sheaths that were shed annually. However, unlike with bison and mountain sheep, there is no evidence in archaeological sites from Clovis to historic times that today's pronghorn are smaller than their late Pleistocene-early Holocene ancestors. This chapter also discusses ethnological and historical evidence of pronghorn hunting and prehistoric pronghorn procurement.

This chapter studies the period when Alexander and Kellogg were forced to stay in Innisfail Ranch. This due to the First World War, as well as a number of issues they needed to attend to at the ranch. The discussion notes that not only did it severely limit Alexander and Kellogg's ability to conduct fieldwork, but also created an intense longing for the world beyond the ranch. It was also during this time that Alexander's mother died, and that Alexander started funding Beckwith's personal business venture in New York City. A period of peace in the ranch coincided with the end of the war, which allowed the women to go back to fieldwork. The chapter follows several of their exploits, including a summer trip to the Sequoias, which renewed Alexander's vitality. It also notes their most important fossil-hunting expedition during this period, which was an excursion to the Miocene formations in the Mojave Desert.

The eight widespread clades of New World monkeys are examined, and the distributional breaks in the clades are compared. The breaks and overlaps are related to the Cretaceous and Cenozoic tectonics of the region. Overlap among the main clades is attributed to Cretaceous marine incursions, while overlap among lower-level clades may reflect Miocene marine seas. Phylogenetic breaks are related to tectonic events, including the uplift of the Andes and the failed rifting along the Amazon, which themselves were caused by the opening of the Atlantic. Maximum primate diversity in western Amazonia is attributed to the same foreland basin tectonics that produced belts of major oil fields in the region.

This chapter attempts to trace the stages of the brain evolution of the first hominids. Molecular biological studies set the emergence of the family of Hominidae as a late Miocene phenomenon, about 6.4 to 5 million years before the present (myr BP). This chapter considers that the fossil calvariae or endocranial casts from that time is valuable as it presents a good starting point for the study of the evolution of the hominid brain. The chapter asserts that on the basis of the evidence presented and examined on the brain of various australopithecines, there is a relative small increase in absolute and relative endocranial capacity between the brains of australopithecines and of present day chimpanzees. However, the chapter shows in the latter part how the Homo habilis marks the first appearance of a disproportionately enlarged brain size similar to the brain of mmodern mankind.

This chapter examines the biogeography of marine incursions in South America. It summarizes evidence for marine incursions into the continental interior during the Miocene period and considers the effects of these paleogeographic events on the diversification of Neotropical fishes. It identifies some of the main biological factors that may have allowed for the successful invasion of Neotropical freshwaters, including origins from euryhaline or estuarine ancestors with high tolerance for salinity fluctuations.

This book addresses the geology, geochronology, paleontology, paleogeography, paleobiochronology, and paleoecology of the Middle Awash late Miocene. It synthesizes vertebrate evolution in eastern Africa during the end of the Miocene epoch, a time during which the modern African fauna started forming. The Middle Awash valley of Ethiopia is a unique natural laboratory for the study of human origins and evolution. This introductory chapter provides a historical overview of the Middle Awash research project, which was formed to conduct geological, paleoanthropological, and archaeological reconnaissance surveys in the area.

This chapter describes the Middle Awash carnivore fauna, which represents one of the most diverse in the latest Miocene of eastern Africa. At least 15 genera in seven families are recognized from the Asa Koma Member of the Adu-Asa Formation and the Kuseralee Member of the Sagantole Formation. The carnivore assemblage from the late Miocene of the Middle Awash has important implications for regional and global biogeography, and it also documents the first local appearances of some taxa that established the modern African carnivore fauna.

This chapter discusses the phylogenetic relationships among African suids. It describes cranial and dentognathic suid remains from the late Miocene of the Middle Awash study area. The available fossil suid sample has increased enormously since the 1980s with the discovery of specimens from sites such as Lothagam and the Middle Awash. The chapter suggests that these collections provide deeper insights into the systematics and diversity of African tetraconodont suids during the late Miocene and early Pliocene.

This chapter conducts comparative biogeographic analyses to examine how much the Middle Awash fauna resembles faunas from other localities of similar age at the genus level. The results indicate that the Middle Awash had close biogeographic relationships with eastern and northern African, Arabian, and western Eurasian localities of similar age. The analysis of Eurasian and African late Miocene localities provides information about the first and last occurrences of the taxa considered, and the geographic areas of these recorded occurrences. It also allows us to consider hypotheses about the timing and direction of paleogeographic connections between western Eurasia and northern and eastern Africa during the late Miocene.

The Middle Awash late Miocene faunal assemblages document diverse evolutionary trajectories for mammalian species across the Miocene-Pliocene boundary. The assemblages indicate a number of originations and extinctions in various groups adapted to different habitats. This chapter examines the biochronological and evolutionary significance of the Middle Awash faunal assemblages by looking at possible first appearance (FA) and last appearance (LA) of mammalian species. It synthesizes the information to look into faunal turnovers and their probable causes. The fact that the Middle Awash late Miocene fauna samples two time successive horizons, dated to between 5.8 Ma and 5.2 Ma, makes it ideal to look into what factors trigger evolutionary changes in a lineage.

This concluding chapter summarizes the importance of the Middle Awash late Miocene faunal assemblages in terms of their contribution toward our understanding of the diversity, evolutionary history, and evolutionary tempo and mode of eastern African late Miocene mammals. It also summarizes the results from the paleoenvironmental and paleobiogeographic analyses in relation to regional and global climatic changes and their impact on the speciation and extinction of various mammalian taxa and the formation of the modern African mammalian fauna. Finally, it addresses future plans for continued paleontological work on the late Miocene of the Middle Awash paleontological study area, highlighting the significance of the site and the need for a long-term maintenance and protection program.

While the Neogene record of fossil mammals in Africa is considerably more substantial than that of the Paleogene, it remains far from the relative completeness of the record in, for example, Europe and North America. Many West and Central African countries are completely devoid of a Neogene mammal record, while other countries have only a handful of localities that at best serve as a modest window into what might exist there. Even in regions or countries where there is a record, such as South Africa, that record is very uneven. In some regions, such as the Turkana Basin of northern Kenya and southern Ethiopia, the dating is unsurpassed. In other regions, such as the Miocene of southern and northern Africa, dating is poor and controversial, dependent mainly on biochronologic correlations with faunas outside Africa. Finally, the dating of karstic cave sites such as the australopithecine sites in Gauteng and Limpopo provinces of South Africa is notoriously difficult and rife with controversy. This chapter provides a brief overview of several African sites that have yielded mammalian fossils and their chronology.

The lorisiformes are a group of strepsirrhine primates, comprising the extant galagos and lorisids, that are included together in the superfamily Lorisoidea. They share with other crown strepsirrhines the possession of a specialized tooth comb, comprising the lower canines and incisors, reduced upper incisors with a broad central diastema, and a toilet claw on the second pedal digit. Molecular, karyological, and anatomical studies confirm that galagos and lorisids are monophyletic with respect to lemuriforms from Madagascar. Earlier molecular studies produced contradictory results concerning the monophyly of lorisids and galagids, respectively. The galagos are included together in a single family, the Galagidae, restricted to sub-Saharan Africa. The later Tertiary fossil record of Lorisiformes is quite poor, being restricted to material from the middle to late Miocene of the Siwalik Group of northern Pakistan and to Miocene and Plio-Pleistocene localities in Africa.

Old World monkeys are some of the most common and visible components of the modern mammalian fauna of Africa, and are the dominant nonhuman primates in Africa today with respect to the overall numbers of species present and the number of ecological zones inhabited. What is rarely appreciated is that Old World monkeys have risen to a position of ecological dominance among primates only recently in geological time. During the early and middle Miocene, the Cercopithecoidea were well established in Africa, but not taxonomically diverse. The absence or near absence of monkey fossils from prolific early Miocene sites like Rusinga Island suggests that the animals were genuinely rare elements of the mammalian fauna at the time. The earliest African cercopithecoids belong to the Victoriapithecidae, an extinct family from the early to middle Miocene of eastern Africa that exhibit a mosaic of basal catarrhine and modern Old World monkeylike morphological features. This chapter describes the systematic paleontology of Cercopithecoidea.

The order Creodonta was first named by Cope (1875) and removed from its original placement in the order Carnivora. Some researchers still maintain that creodonts and carnivorans (or carnivoramorphans) are sister taxa, though not all agree. While creodonts and carnivorans share an ossified tentorium and a few basicranial and tarsal features, their possible synapomorphies are few. Like carnivorans, creodonts vary greatly in their postcranial adaptations. Unlike carnivorans, most creodonts have fissured terminal phalanges, with the exception of the European Proviverrinae, and an unfused scaphoid and lunate. All known Afro-Arabian creodonts belong to the family Hyaenodontidae and range in age from the Eocene (and possibly Paleocene) to the middle Miocene. While the earliest African members of this family are found in the north, this family eventually spread southward into eastern and southern Africa. In Africa, as elsewhere, this family is diverse both in body size and morphology, with body size ranging from some of the smallest of forms to the largest hyaenodontid known (Megistotherium). This chapter describes the systematic paleontology of Creodonta.

The order Insectivora was formerly used to comprise a miscellany of eutherians with primitive characters, thought to be relatively little modified descendants from the ancestral eutherian stock. Subsequent investigations of eutherian phylogeny have resulted in the removal of a number of insectivoran families to separate orders. The African families consist of the Macroscelididae (order Macroscelidea), Tenrecidae, Chrysochloridae (order Tenrecoidea), Erinaceidae, and Soricidae. Erinaceidae and Soricidae have a wide distribution outside Africa, with a fossil record going back to the Eocene, but they appear in Africa only in the Miocene, as immigrants. This chapter describes the systematic paleontology of Neogene Insectivora.