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Polar regions modulate the global climate system across human and geological timescales. A new deep-sea study highlights how the Southern Ocean became the distinctive ecoregion it is today. [ABSTRACT FROM AUTHOR]

The microfossil record contains abundant, diverse, and well‐preserved fossils spanning multiple trophic levels from primary producers to apex predators. In addition, microfossils often constitute and are preserved in high abundances alongside continuous high‐resolution geochemical proxy records. These characteristics mean that microfossils can provide valuable context for understanding the modern climate and biodiversity crises by allowing for the interrogation of spatiotemporal scales well beyond what is available in neo‐ecological research. Here, we formalize a research framework of "micropaleoecology," which builds on a holistic understanding of global change from the environment to ecosystem level. Location: Global. Time period: Neoproterozoic‐Phanerozoic. Taxa studied: Fossilizing organisms/molecules. Our framework seeks to integrate geochemical proxy records with microfossil records and metrics, and draws on mechanistic models and systems‐level statistical analyses to integrate disparate records. Using multiple proxies and mechanistic mathematical frameworks extends analysis beyond traditional correlation‐based studies of paleoecological associations and builds a greater understanding of past ecosystem dynamics. The goal of micropaleoecology is to investigate how environmental changes impact the component and emergent properties of ecosystems through the integration of multi‐trophic level body fossil records (primarily using microfossils, and incorporating additional macrofossil data where possible) with contemporaneous environmental (biogeochemical, geochemical, and sedimentological) records. Micropaleoecology, with its focus on integrating ecological metrics within the context of paleontological records, facilitates a deeper understanding of the response of ecosystems across time and space to better prepare for a future Earth under threat from anthropogenic climate change. [ABSTRACT FROM AUTHOR]

As the demand for sustainable polymers increases, most research efforts have focused on polyesters, which can be bioderived and biodegradable. Yet analogous polythioesters, where one of the oxygen atoms has been replaced by a sulfur atom, remain a relatively untapped source of potential. The incorporation of sulfur allows the polymer to exhibit a wide range of favorable properties, such as thermal resistance, degradability, and high refractive index. Polythioester synthesis represents a frontier in research, holding the promise of paving the way for eco‐friendly alternatives to conventional polyesters. Moreover, polythioester research can also open avenues to the development of sustainable and recyclable materials. In the last 25 years, many methods to synthesize polythioesters have been developed. However, to date no industrial synthesis of polythioesters has been developed due to challenges of costs, yields, and the toxicity of the by‐products. This review will summarize the recent advances in polythioester synthesis, covering step‐growth polymerization, ring‐opening polymerization (ROP), and biosynthesis. Crucially, the benefits and challenges of the processes will be highlighted, paying particular attention to their sustainability, with the aim of encouraging further exploration and research into the fast‐growing field of polythioesters. [ABSTRACT FROM AUTHOR]

New biostratigraphically constrained chronologies have been developed to help elucidate the sedimentary and tectonic history of Quaternary sequences on the Hikurangi margin of north-eastern Zealandia. Three sites on the mid to lower slope of the accretionary prism (IODP Site 372-U1517, 375-U1519, 375-U1518) and two sites east of the deformation front (Hikurangi Trough Site 375-U1520 and Tūranganui Seamount Site 375-U1526) are dated using a detailed biostratigraphic framework based on planktic foraminiferal records from ODP Site 181-1123. The dating indicates sedimentation rates are very high and variable on the accretionary prism (0.2–9.6 m/kyr), especially during the Last Glacial Maximum (LGM) when downslope redeposition from the continental shelf and upper slope is common. Sedimentation rates at Hikurangi Trough Site 375-U1520 are also variable (0.01–3.0 m/kyr) and they increase markedly as the incoming site approached the deformation front, especially during the LGM, due to an abundance of downslope redeposition from the inner to mid shelf. The incoming Quaternary section at Tūranganui Seamount Site 375-U1526, is punctuated by hiatuses that shorten in duration as the site approached the deformation front, whilst sedimentation rates remain relatively low (0.04–0.4 m/kyr). [ABSTRACT FROM AUTHOR]

Zealandia has very few biostratigraphic markers to help elucidate the often complex and discontinuously cored stratigraphy of Quaternary sequences on the margins and submarine plateaux of the subcontinent. In this study, a detailed biostratigraphic framework has been developed to help unravel the complex stratigraphy of tectonically deformed Quaternary sediments on the Hikurangi margin of north-eastern Zealandia. The framework is based on well documented and dated 0–1.2 Ma planktic foraminiferal records from Ocean Drilling Project (ODP) Site 181–1123 on the Chatham Rise, just north of the Subtropical Frontal Zone. The framework has 104 biostratigraphic markers and is subdivided using the Sinistral Truncorotalia truncatulinoides Zone (STZ) 0–533 ka, the Dextral Tr. truncatulinoides Zone (DTZ) 533–2440 ka, the lowest common occurrence (LCO) Tr. truncatulinoides (621 ka), the highest common occurrence (HCO) Neogloboquadrina pachyderma (624 ka), and the HCO Tr. crassacarina (1101 ka). Further subdivision is then based on the tops and bases of short-lived climatically-tempered influxes of Globigerinoides ruber, Hirsutella hirsuta, Hr. praehirsuta, Tr. truncatulinoides, Tr. crassacarina, and Nq. pachyderma. Most of these biostratigraphic markers are not unique, but sequences of markers that are unique to each marine isotope stage provide an unprecedented level of biostratigraphic detail and chronological dating when they are used within the contextual chronological framework of keystone biostratigraphic markers. [ABSTRACT FROM AUTHOR]

Machiavelli and the Orders of Violence, by Yves Winter. Cambridge: Cambridge University Press, 2018. 230 pp. In the opening pages of Machiavelli and the Orders of Violence, Yves Winter outlines [...]

he Plio-Pleistocene is associated with many important climatic and paleoceanographic changes which have shaped the biotic and abiotic nature of the modern world. The closure of the Central American Seaway and the development and intensification of northern hemisphere icesheets had profound global impacts on the latitudinal and vertical structure of the oceans triggering the extinction and radiation of many marine groups. In particular, marine calcifying planktonic foraminifera, that are sensitive to water column structure, exhibited a series of extinctions as global temperatures fell. By analyzing high-resolution (~5 kyr) sedimentary records from the Eastern Equatorial Pacific Ocean, complimented with global records from the novel Triton dataset, we document the biotic changes in this microfossil group, within which three species displayed isochronous co-extinction, and species with cold-water affinity increase in dominance. We suggest that these changes are associated with the terminal stages of the closure of the Central American Seaway and mark the initiation of a world in which cold- and deep-dwelling species became increasingly more successful. [ABSTRACT FROM AUTHOR]