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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available 40Ar/39Ar data for the Adu-Asa Formation, including some data not previously reported, plus some previously unpublished results from the nearby Central Awash Complex (CAC).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.

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 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 above quote by the German poet, novelist, and painter Herman Hesse highlights the cultural significance of forests in nineteenth- and twentieth-century western culture as the ‘natural’ contrast to growing urban populations and industrial expansion. Hesse’s focus on the ‘ancient’ element of these environments is certainly valid in a tropical context, given that tropical forests are some of the oldest land-based environments on the planet, existing for over one thousand times longer than Homo sapiens (Upchurch and Wolf, 1987; Davis et al., 2005; Ghazoul and Shiel, 2010; Couvreur et al., 2011). This antiquity also makes them one of the richest and most diverse terrestrial ecosystems on the planet (Whitmore, 1998; Ghazoul and Shiel, 2010). Tropical rainforests, for example, contain over half of the world’s existing plant, animal, and insect species (Wilson, 1988). A significant portion of the developed world’s diet today originated in tropical forests—including staples such as squash and yams, spices such as black pepper, cinnamon, cloves, and sugar cane, and fruits including bananas, coconuts, avocados, mangoes, and tomatoes (Iriarte et al., 2007; Roberts et al., 2017a). Tropical forests also often provide ample freshwater for their inhabitants. However, despite popular perceptions of forests, and specifically tropical forests, as uniform, they are, in fact, highly variable across space and time. In tropical evergreen rainforests productivity is often primarily allocated to wood products, meaning that edible plants and animals for human subsistence have been considered lacking, or at least more difficult to extract, relative to more open tropical forest formations (Whitmore, 1998; Ghazoul and Shiel, 2010). Similarly, while evergreen tropical rainforests generally receive significant precipitation and freshwater, seasonally dry tropical forests are subject to sub-annual periods of aridity. Therefore, while archaeologists and anthropologists have tended to see ‘tropical forest’ as a uniform environmental block, it is important to explore the diversity within this category.

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 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 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.

Fossils provide some of the most detailed sources of information for environmental reconstruction available to the paleolimnologist. The use of lacustrine fossils to infer paleoenvironmental conditions is fundamentally based on inferences derived from modern correlations between the distribution of organisms and environmental variables, coupled with an understanding of taphonomy, the study of the fossilization process. No single group of organisms provides a comprehensive picture of lake ecosystems or environmental change, so it is always desirable to gather paleoecological records from multiple clades and habitats in a paleolimnological study. Analysis of multiple clades provides a means of establishing or testing ecological hypotheses that may not be possible from the study of one group alone. For example, many limnological processes affect the plankton, littoral organisms, and benthos in predictable sequences, and with predictable intensities. The most comprehensive study of fossil data and data analysis will be meaningless if the fossils studied are misidentified. A good taxonomic framework is an essential element of paleoecological studies. Accurate identification of described species, and the curation of voucher specimens, photographs, and other descriptive materials of undescribed species is important, to insure the quality of a paleolimnologist’s ongoing work, and to avoid future errors based on previously misidentified fossil specimens. Using fossils to interpret lacustrine paleoenvironments requires not only an understanding of modern organism distributions, but also an understanding of four additional factors we did not consider in chapter 5: (1) ecological causality and scale, (2) taphonomy and time-averaging, (3) historical contingency, and (4) evolutionary processes. One of the most common uses of fossil data in lakes is to try and reconstruct changes in some physical or biological forcing process from changes in abundance or morphology of the fossil organisms affected by the process. We might be interested in reconstructing changes in nutrient flux to the lake, based on changes in the relative abundances of some fossil animals. However, these animals actually responded to nutrient load only indirectly, through the effect of nutrient load on autotrophs and/or organic detritus. Now suppose that our ultimate objective is not really to understand productivity changes or nutrients, so much as to understand climate changes that may be driving productivity changes.

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.