The East African Rift System (EARS) has played a central role in our understanding of human origins and vertebrate evolution in the late Cenozoic of Africa. However, the distribution of fossil sites along 3 the rift is highly biased toward its northern extent, and the types of paleoenvironments are primarily restricted to fluvial and lacustrine settings. Here we report the discovery of the first fossil sites from the Urema Rift at Gorongosa National Park (central Mozambique) at the southern end of the EARS, and reconstruct environmental contexts of the fossils. In situ and surface fossils from the lower member of the Mazamba Formation, estimated to be of Miocene age, comprise mammals, reptiles, fishes, invertebrates, palms, and dicot trees. Fossil and geological evidence indicates a coastal-plain paleoenvironmental mosaic of riverine forest/woodland and estuarine habitats that represent the first coastal biomes identified in the Neogene EARS context. Receiving continental sediment from source terranes west of today's Urema Graben, estuarine sequences accumulated prior to rifting as compound incised-valley fills on a low-gradient coastal plain following transgression. Modern environmental analogues are extremely productive habitats for marine and terrestrial fauna, including primates. Thus, our discoveries raise the possibility that the Miocene coastal landscapes of Gorongosa were ecologically-favorable habitats for primates, providing relatively stable maritime climate and ecosystem conditions, year-round freshwater availability, and food both from terrestrial and marine sources. The emerging fossil record from Gorongosa is beginning to fill an important gap in the paleobiogeography of Africa as no fossil sites of Neogene age have previously been reported from the southernmost part of the EARS. Furthermore, this unique window into past continentalmargin ecosystems of central Mozambique may allow us to test key paleobiogeographic hypotheses during critical periods of primate evolution.

51Massive fossil shell accumulations require particular conditions to be formed and may 52 provide valuable insights into the sedimentary environments favouring such 53 concentrations. Shallow-water shell beds appear to be particularly rare on reefless 54 volcanic oceanic islands on account of narrow, steep and highly-energetic insular 55 shelves where the potential for preservation is limited. The occurrence of an exceptional 56 coquina (Pedra-que-pica) within the Miocene-Pliocene deposits of Santa Maria Island 57 (Azores), therefore provides a rare opportunity to understand the conditions that led to 58 the formation and preservation of a massive shell bed at mid-ocean insular setting. This 59 study provides a detailed analysis regarding a 10-11 m-thick bivalve-dominated fossil 60 assemblage exposed at Pedra-que-pica on Santa Maria Island in the Azores. Integration 61 of taphonomical, palaeoecological and sedimentological observations are used to 62 reconstruct the genesis of the coquina bed and related events, and to discuss why such 63 exceptional sedimentary bodies are so rare on shelves around reefless volcanic oceanic 64 islands. 65 The sequence at Pedra-que-pica demonstrates a complex succession of sedimentary 66 environments in response to the drowning of an existing coastline during a period of 67 rapid sea-level rise. The Pedra-que-pica shell bed incorporates storm-related materials 68 and possible debris falls that originated nearby in a shallow and highly productive 69 carbonate factory. Deposition took place below fair-weather wave base, at around 50 m 70 depth, as inferred from the overlying volcanic succession. The preservation of this 71 coquina was favoured by deposition on a platform laterally protected by a rocky spur, 72 combined with rapid burial by water-settled volcanic tuffs and subsequent volcanic 73 effusive sequences. The recent exhumation of the deposit is the result of island uplift 74 and subsequent erosion.75 4 76 77

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The analyses of the stable isotope ratios of carbon (δ13C), nitrogen (δ15N), and oxygen (δ18O) in animal tissues are powerful tools for reconstructing the feeding behavior of individual animals and characterizing trophic interactions in food webs. Of these biomaterials, tooth enamel is the hardest, most mineralized vertebrate tissue and therefore least likely to be affected by chemical alteration (i.e., its isotopic composition can be preserved over millions of years), making it an important and widely available archive for biologists and paleontologists. Here, we present the first combined measurements of δ13C, δ15N, and δ18O in enamel from the teeth of modern fauna (herbivores, carnivores, and omnivores) from the well-studied ecosystem of Gorongosa National Park (GNP) in central Mozambique. We use two novel methods to produce high-precision stable isotope enamel data: (i) the “oxidation-denitrification method,” which permits the measurement of mineral-bound organic nitrogen in tooth enamel (δ15Nenamel), which until now, has not been possible due to enamel’s low organic content, and (ii) the “cold trap method,” which greatly reduces the sample size required for traditional measurements of inorganic δ13Cenamel and δ18Oenamel (from ≥0.5 to ≤0.1 mg), permitting analysis of small or valuable teeth and high-resolution serial sampling of enamel. The stable isotope results for GNP fauna reveal important ecological information about the trophic level, dietary niche, and resource consumption. δ15Nenamel values clearly differentiate trophic level (i.e., carnivore δ15Nenamel values are 4.0‰ higher, on average, than herbivores), δ13Cenamel values distinguish C3 and/or C4 biomass consumption, and δ18Oenamel values reflect local meteoric water (δ18Owater) in the park. Analysis of combined carbon, nitrogen, and oxygen stable isotope data permits geochemical separation of grazers, browsers, omnivores, and carnivores according to their isotopic niche, while mixed-feeding herbivores cannot be clearly distinguished from other dietary groups. These results confirm that combined C, N, and O isotope analyses of a single aliquot of tooth enamel can be used to reconstruct diet and trophic niches. Given its resistance to chemical alteration, the analysis of these three isotopes in tooth enamel has a high potential to open new avenues of research in (paleo)ecology and paleontology.

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Middle to Late Jurassic belemnites from the Spiti and Zanskar valleys in the Indian Himalayas were used for stable isotope (δ13C, δ18O) and element (Mg/Ca, Sr/Ca) analyses. Although the Himalayan orogeny deformed and altered a large portion of the collected fossils, cathodoluminescence and scanning electron microscopy in combination with analyses of iron and manganese contents allowed the identification of belemnites believed to still retain their original chemical composition. Results indicate a long-term temperature decrease from the Middle Callovian–Oxfordian to the Tithonian, which is proposed to have been caused by a concomitant drift of eastern Gondwana into higher palaeolatitudes. Reconstructed absolute temperatures depend on the used equation and assumed δ18O value of seawater, but most likely varied between 17.6 °C to 27.6 °C in the Kimmeridgian and Tithonian with average values between 22 °C to 24 °C. This way, temperatures were similar to slightly warmer than today at comparable latitudes. The reconstruction of absolute temperatures for the Middle Callovian–Oxfordian was hindered by a larger number of poorly preserved belemnites representing this time interval.