Marine sedimentary rocks of the late Eocene Pagat Member of the Tanjung Formation in the Asem Asem Basin near Satui, Kalimantan, provide an important geological archive for understanding the paleontological evolution of southern Kalimantan (Indonesian Borneo) in the interval leading up the development of the Central Indo-Pacific marine biodiversity hotspot. In this paper, we describe a moderately diverse assemblage of marine invertebrates within a sedimentological and stratigraphical context. In the studied section, the Pagat Member of the Tanjung Formation records an interval of overall marine transgression and chronicles a transition from the marginal marine and continental siliciclastic succession in the underlying Tambak Member to the carbonate platform succession in the overlying Berai Formation. The lower part of the Pagat Member contains heterolithic interbedded siliciclastic sandstone and glauconitic shale, with thin bioclastic floatstone and bioclastic rudstone beds. This segues into a calcareous shale succession with common foraminiferal packstone/rudstone lenses interpreted as low-relief biostromes. A diverse trace fossil assemblage occurs primarily in a muddy/glauconitic sandstone, sandy mudstone, and bioclastic packstone/rudstone succession, constraining the depositional setting to a mid-ramp/mid to distal continental shelf setting below fair-weather wave base but above storm wave base. Each biostrome rests upon a storm-generated ravinement surface characterized by a low-diversity Glossifungites or Trypanites trace fossil assemblage. The erosional surfaces were colonized by organisms that preferred stable substrates, including larger benthic foraminifera, solitary corals, oysters, and serpulid annelid worms. The biostromes comprised islands of high marine biodiversity on the mud-dominated Pagat coastline. Together, the biostromes analyzed in this study contained 13 genera of symbiont-bearing larger benthic foraminifera, similar to 40 mollusk taxa, at least 5 brachyuran decapod genera, and 6 coral genera (Anthemiphyllia, Balanophyllia, Caryophyllia, Cycloseris, Trachyphyllia, and Trochocyathus), as well as a variety of bryozoans, serpulids, echinoids, and asterozoans. High foraminiferal and molluscan diversity, coupled with modest coral diversity, supports the hypothesis that the origin of the diverse tropical invertebrate faunas that characterize the modern Indo-Australian region may have occurred in the latest Eocene/earliest Oligocene.

Five out of the original nine syntypes of Astarte pulchella Baily, 1858 (junior synonym of Davidaschvilia ( Zhgentiana ) gentilis (Eichwald, 1851)) are discovered in the Natural History Museum, London. A lectotype is designated, described, and illustrated, paralectotypes are indicated, illustrated and a detailed synonymy of the species is provided. The importance of the species as characteristic of the Karaganian Regional Stage of the Eastern Paratethys, Middle Miocene (= Serravallian) is recognized.

<p>The drawdown of CO<sub>2</sub> via the temperature-dependent weathering of silicate minerals is thought to be one of the key processes acting to maintain Earth’s climate within narrow bounds over geologic time. However, the climatic responsiveness of weathering on multi-million-year timescales is, to our knowledge, yet to be demonstrated. If other factors dominate climate regulation on geologic timsecales, previously unexplored factors may be important in driving long-term carbon cycle changes. Here, we present the first continuous Cenozoic record of the concentration of calcium in seawater ([Ca<sup>2+</sup><sub>sw</sub>]). Our record is based on the Na/Ca of exceptionally well-preserved foraminiferal calcite, a methodology which leverages the extremely long seawater Na<sup>+</sup> residence time (>40 Myr) to interpret such changes predominantly in terms of [Ca<sup>2+</sup><sub>sw</sub>] fluctuation. We show that a 12 mM decrease in [Ca<sup>2+</sup><sub>sw</sub>] occurred over the last ~50 Ma, with a close correspondence to the timing of atmospheric CO<sub>2</sub> changes, potentially implying a common driver. Using a carbon cycle box model, we demonstrate that, if the relationship between silicate weathering is shallower than commonly assumed, then this change in [Ca<sup>2+</sup><sub>sw</sub>] can mechanistically explain the majority of the Cenozoic CO<sub>2</sub> decrease, via the effect that Ca<sup>2+</sup> has on CaCO<sub>3</sub> burial rates. Given the recently identified major change in the global sea floor spreading rate, this finding shifts the key driver of long-term climate from the terrestrial to marine realm. Conversely, if there is a steep relationship between silicate weathering and climate, the climatic responsiveness of weathering is such that the system would rebalance before [Ca<sup>2+</sup><sub>sw</sub>] can drive a major CO<sub>2</sub> change. Our results therefore highlight the need to determine whether silicate weathering is responsive to climate change on geologic timescales before the long-term drivers of CO<sub>2</sub> can be determined.</p>

We often wish to classify objects by their shapes. Indeed, the study of shapes is an important part of many scientific fields, such as evolutionary biology, structural biology, image processing and archaeology. However, mathematical shape spaces are rather complicated and nonlinear. The most widely used methods of shape analysis, geometric morphometrics, treat the shapes as sets of points. Diffeomorphic methods consider the underlying curve rather than points, but have rarely been applied to real-world problems. Using a machine classifier, we tested the ability of several of these methods to describe and classify the shapes of a variety of organic and man-made objects. We find that one method, based on square-root velocity functions (SRVFs), outperforms all others, including a standard geometric morphometric method (eigenshapes), and that it is also superior to human experts using shape alone. When the SRVF approach is constrained to take account of homologous landmarks it can accurately classify objects of very different shapes. The SRVF method identifies a shortest path between shapes, and we show that this can be used to estimate the shapes of intermediate steps in evolutionary series. Diffeomorphic shape analysis methods, we conclude, now provide practical and effective solutions to many shape description and classification problems in the natural and human sciences.

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Summary. A wide range of geomaterials were worked at industrial settlements scattered over an area of c.225 km 2 in the Poole Harbour–Isle of Purbeck district of modern Dorset. These materials, more than one handled at some sites, included shale (‘coal’), burnt shales (yellow, red) and cementstones from the Kimmeridge Clay Formation (Upper Jurassic), Purbeck marble from the Purbeck Group (earliest Cretaceous), hard chalk from the Chalk Group (Upper Cretaceous), and potting clays and sands from the Bracklesham Group (Palaeogene), for South‐east Dorset Black‐burnished Pottery Category 1. There was also a salt industry, which could have used pottery for packaging. The industrial products are conterminously distributed in southern and central Britain and, in the case of pottery and shale items, reached as far as the northern frontiers. Raw material of red burnt shale was exported to Silchester ( Calleva Atrebatum ), where it was made into mosaic tesserae. Of proven Kimmeridgian age on the evidence of fossils, the mudstone used to make it had been collected and quarried on the coast of the Isle of Purbeck before being burnt. The decline in the demand for stone products, excepting shale, in the second century AD saw an expansion of the potting industry, which persisted into the fifth century. The term complex‐agglomerative is introduced to describe this diverse and dispersed enterprise at this highest hierarchical level, examples of which occur elsewhere in the Roman world.

While the encrustation of floating driftwood by pseudoplankton has attracted much debate, the utilization of benthic xylic substrata by sessile organisms has received scant attention. Here we record a benthic woodground fauna, including weakly mineralized and entirely soft-bodied taxa, which have been preserved within the cement of an overgrowing oyster. This process, bioimmuration, is ubiquitous in marine hard-substrate communities but is recorded here on a xylic substrate for the first time. Comparison of bioimmured communities will allow investigation of changes in woodground fauna through time and offers the potential for a fuller understanding of the effect of substrate texture on community composition.

Outlines of soft‐bodied sessile epibionts that grew attached to the surfaces of calcareous shells in ancient seas are sometimes preserved by a process termed ‘Epibiont Shadowing’. Processes that altered the surface of the shell were prevented from happening immediately beneath the attached epibiont, leaving a shadow of its attachment site following its death and decay. Microboring around the perimeter of the epibiont by presumed endolithic cyanobacteria gave rise to Endolithic Shadows, and dissolution of the calcareous substrate, maybe beneath larger smothering organisms, produced Solution Shadows of smaller organisms that protected their sites of attachment from such etching effects. Recognition of this type of preservation allows the stratigraphic range of certain soft‐bodied groups to be extended. Details of the shadows may yield information about the morphological construction of the groups in question.