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This chapter considers the paleoenvironment of the Middle Awash study area in the Afar Rift of Ethiopia. Different aspects of the large mammalian faunal communities from the Asa Koma and Kuseralee Members are examined. The chapter examines the community structure based on locomotor and dietary variables, relative abundances of indicator taxa, and ecomorphology. Independent verification of the results based on large mammalian fauna have been derived from fish, bird, and small mammal faunas and from geological and stable isotopic data.

This chapter summarizes the latest findings on late Miocene fossils from the Baynunah Formation in the United Arab Emirates. Since 1999, fossil discoveries have continued to be made in the late Miocene Baynunah Formation in Al Gharbia, Abu Dhabi Emirates. By way of biochronology, the Baynunah fossil fauna is estimated to be between 8 Ma and 6 Ma. No other terrestrial fossil sites of late Miocene age are known from the remainder of the Arabian Peninsula. Hence, the Baynunah fauna represents the sole sample available to chart the biotic continuity between late Miocene Arabia and neighboring contemporaneous fossil sites in Asia. This chapter first describes the paleoenvironments and paleobiogeography of the Baynunah Formation before turning to a discussion of its fossil biota.

This chapter, which presents and reviews a database of 383 citations that refer to more than 1,000 bonebeds, offers additional insight into how bonebeds formed in the past and what they can tell us about the ancient environments within which they formed. Its goals are to: identify, characterize, and document different types of bonebed; identify historical and scientific biases in the treatment of bonebeds; demonstrate the relative frequency of different types of bonebed in the database; identify and quantify patterns of occurrence for the different types of bonebed; and identify and quantify patterns of association between bonebed type and paleoenvironment. Most bonebeds in the database are easily classified using one or more of the following three measures: element size, taxonomic diversity, and relative taxonomic abundance. In addition, patterns of occurrence are identified in relation to the relative abundance of different types of bonebed, inferred mechanisms of origin, and recurrent associations of bonebed type and paleoenvironment.

The Congo River functions as a strong geographical barrier for many terrestrial mammals in the Congo Basin, separating forest habitat into right and left banks of the river. However, there has been little discussion on the biogeography of the Congo Basin because the history of the river has been obscured. Based on the recent information of the sea-floor sediments near the mouth of the river and the geophysical survey on the continent, this chapter proposes a plausible hypothesis on the Congo River formation and presents a consequent hypothesis on the divergence of bonobos (Pan paniscus) from other Pan populations. The present hypothesis is also helpful for understanding the distribution of other primates and other mammals in the basin. Furthermore, this hypothesis suggests that all hominid clades, including human, chimpanzee and gorilla, except bonobo, evolved in the area north or east of the Congo River. La rivière du Congo a la fonction d’une barrière géographique forte pour plusieurs mammifères dans le bassin du Congo, séparant l’habitat forêt dans les banques gauches et droites de la rivière. Cependant, il y a eu peu de discussions sur la biogégraphie du bassin du Congo, parce que l’histoire de la rivière a été voilée. Récemment, quelque données importantes qui peuvent avoir des liens avec la formation de la rivière du Congo ont été acquise, surtout par la recherche des sédiments du fond marin près de la bouche de la rivière et par l’enquête géographique du continent. À partir de cette nouvelle information, nous avons proposé une hypothèse plausible sur la formation de la rivière du Congo. Nous avons aussi présenté une hypothèse conséquente sur la divergence des bonobos (Pan paniscus) des autres populations Pan (voire Takemoto et al., 2015 pour la publication originale de cette étude). L’hypothèse présente nous aide aussi à comprendre la distribution des autre primates et des autres mammifères dans le bassin. De plus, cette hypothèse suggère que tous les hominidés clades, humains inclus, chimpanzés et gorilla à l’exception du bonobo, ont évolué dans la régions du nord ou de l’est de la rivière du Congo.

The stoichiometry of pyrite in framboids is unknown. The trace element content of framboids has been reported since framboids usually constitute the earliest pyrite phase in a sediment and therefore are more likely to pick up trace element variations in contemporary seawater. The trace element ratios in sedimentary framboids are similar to those in the host shales. Analyses of hydrothermal framboids are fewer, and As, Sb, and Tl appear to be enriched in hydrothermal framboids, with As, Sb, Ni, and Co also being enriched in framboids formed during metamorphism. In contrast with trace element distributions, no spatial variations in sulfur isotopic compositions have been reported within individual framboids. Framboids pick up a more accurate measure of the sulfur isotopic composition of the prevailing dissolved sulfide and are likely to retain this over geologic time. Although it is probable that pyrite framboids collect the local environmental trace element variations, interpretations of the results in terms of paleoenvironmental reconstructions are currently complex. The original sequestration of trace elements is likely to be in part determined by the pyrite crystal chemistry, and there may be a limit to how much of any given trace element can be sequestered by pyrite. This is likely to be enhanced during late diagenesis and early metamorphism and it is not altogether clear how individual trace elements behave over geologic time.