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.

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Increasing global temperature and sea-level rise have led to concern about expansions in the distribution and prevalence of complex-lifecycle parasites (CLPs). Indeed, numerous environmental variables can influence the infectivity and reproductive output of many pathogens. Digenean trematodes are CLPs with intermediate invertebrate and definitive vertebrate hosts. Global warming and sea level rise may affect these hosts to varying degrees, and the effect of increasing temperature on parasite prevalence has proven to be nonlinear and difficult to predict. Projecting the response of parasites to anthropogenic climate change is vital for human health, and a longer term perspective (10 4 y) offered by the subfossil record is necessary to complement the experimental and historical approaches of shorter temporal duration (10 −1 to 10 3 y). We demonstrate, using a high-resolution 9,600-y record of trematode parasite traces in bivalve hosts from the Holocene Pearl River Delta, that prevalence was significantly higher during the earliest stages of sea level rise, significantly lower during the maximum transgression, and statistically indistinguishable in the other stages of sea-level rise and delta progradation. This stratigraphic paleobiological pattern represents the only long-term high-resolution record of pathogen response to global change, is consistent with fossil and recent data from other marine basins, and is instructive regarding the future of disease. We predict an increase in trematode prevalence concurrent with anthropogenic warming and marine transgression, with negative implications for estuarine macrobenthos, marine fisheries, and human health.parasites | disease | global warming | paleoecology | mollusks P redictions for the increase of global temperature and concomitant sea-level rise in the coming decades and centuries have led to concerns about the range expansion or shift of parasites and pathogens to higher latitudes, resulting in an increase in prevalence and severity of diseases. Indeed, environmental factors such as temperature, humidity, and precipitation can strongly influence the infectivity and reproductive output of many pathogens (1, 2); however, the life cycles of parasites can be quite complex, and accurately predicting how their prevalence will be influenced by these factors can be difficult. For example, digenean trematodes are complex-lifecycle parasites (CLPs) with multiple intermediate invertebrate hosts and a definitive vertebrate host. Environmental change may affect each of these hosts to varying degrees, such that a modest increase in temperature could result in an increase of parasite reproductive output and infectivity. However, a more severe increase in temperature could be beyond the thermal tolerance of one of the hosts, thus ultimately resulting in a decrease in prevalence (3)(4)(5). Still other studies have produced quantitative models and compared spatial and temporal (seasonal-to historical-scale) aspects of climatic and other environmental variables with outbreak data i...

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