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The vacant niches left by the non-avian dinosaurs and other vertebrates after the end-Cretaceous mass extinction, provided a crucial opportunity for placental mammal diversification. The general neurosensory organization exhibited by extant mammals has been maintained since the Late Triassic-Early Jurassic. Much later during the Eocene, fossils of early members of extant placentals display neurosensory innovations, such as a proportionally larger neocortex and a higher encephalization quotient (EQ), compared to their Mesozoic ancestors. However, few studies have focused on the brain of the oldest placentals that lived during the Paleocene. We analysed the neurosensory system of two species of arctocyonid ‘condylarths’, a likely nonmonophyletic group, including some species potentially implicated in the origins of extant ungulates. ‘Arctocyonids’ were of small-to-medium size, omnivorous and mainly terrestrial. We obtained cranial and bony labyrinth endocasts for Arctocyon and two species of Chriacus using high-resolution computed tomography. Both species exhibit plesiomorphic features shared with other early Paleocene mammals such as a relatively small lissencephalic brain with an EQ range of 0.07-0.31 using Eisenberg’s equation. The olfactory bulbs and the petrosal lobules represent 7% and less than 1% of the total endocranial volume, respectively. The neocortical height represents ~25% of the total endocranial height. Based on the cochlea, these species had hearing capabilities similar to extant wild boars. Agility scores between 2 and 3, show that these taxa were similar to the American badger and the crab-eating raccoon, suggesting that Arctocyon and Chriacus were moderately agile. These results support the growing evidence that early placentals had low EQs and less expanded neocortices compared to Eocene and later taxa, potentially indicating that complex neurosensory organization was not key to the placental radiation after the end-Cretaceous mass extinction. This research has been funded by Marie Sklodowska-Curie Actions: Individual Fellowship, European Research Council Starting Grant, National Science Foundation, and Belgian Science Policy Office.

Paleogene mammal localities are particularly well represented in the area of Erlianhot, Inner Mongolia. Among them, the locality of Bayan Ulan is most famous for its late Paleocene Gashatan fauna. The Arshantan fauna of the site is not well known, since no extensive study has been done so far. Here we present a mammal assemblage based on dental and tarsal material from a new Arshantan collection resulting from excavations done by a Belgian-Chinese expedition in Inner Mongolia in 1995 – retrieved from the red beds of the late early to early middle Eocene Arshanto Formation at Bayan Ulan. It consists of at least six different taxa: the primitive lagomorph Dawsonolagus antiquus, the large pantodont Pantolambdodon sp., the lophialetid tapiroid Schlosseria magister, the rhinocerotoid Hyrachyus crista, and a new smaller rhinocerotoid. The latter is closely related to the genera Yimengia and Rhodopagus. The species exhibits transverse Hunter-Schreger bands, no reduction of the lower premolars, m3 has no hypoconulid, and P4 bears a continuous “V”-shaped protolophmetaloph loop. The Arshantan assemblage at Bayan Ulan is dominated by small perissodactyls, represented by extensive lower and upper dentition as well as foot bones. Also, for the first time, p4-m1 of Dawsonolagus antiquus, tarsal material from Pantolambdodon, and lower dentition of Hyrachyus crista are illustrated. Unlike other described Arshantan faunas, the Bayan Ulan Arshantan mammal assemblage has been collected exclusively from a single locality, which allows it to be used in the reassessment of the Arshantan Land Mammal Age. This research has been funded by project MO/36/011 and bilateral cooperation project BL/36/C12 of the Belgian Federal Science Policy Office.

In the Paris Basin, marine deposits of the Vesles and Montagne de Laon Groups bracket terrestrial to littoral litho-units of the Mont Bernon Group. Since 2007, we study those Sparnacian facies, as they record the effects of a climate crisis linked to a massive release of greenhouse gases into the atmosphere. This hyperthermal event, the Paleocene Eocene Thermal Maximum (PETM), occurred 55.8 Ma ago, was brief (170 ka) and intense (+ 5 to 8°C vs. baseline). Studied as an analogue to the current global warming, it is marked by a negative isotopic excursion of 2 to 6 ‰ of the δ13C and coincides with environmental perturbations. About thirty reference successions have been studied, to which well-described information is incorporated, providing a comprehensive and detailed set of geological data. The aim is to 1) revise the lithostratigraphic nomenclature by integrating new δ13Corg and biostratigraphic data, 2) establish well-calibrated correlations in these series prone to hiatuses and lateral facies changes, 3) build a robust framework to reconstitute and discuss the evolution of landscapes, flora and fauna. We show a prominent record of the PETM over 15-25 m, marked by a strong increase in the sedimentation rate. Steps identified in the δ13Corg curves enable fine correlation, 1) especially at the beginning of the event in fluvial and more rarely lagoonal to lacustrine environments, 2) then in alluvial plains, with development of calcretes and variegated paleosols, 3) and in swamps, lakes and lagoons, formed in a context of rising waterlevel. We further observe faunal and floral turnovers, eutrophication of aquatic environments, extreme acme of Apectodinium and few other dinoflagellate cyst groups as well as the occurrence of new dinoflagellate species. Lateral facies variations are anchored and paleogeographic maps drawn. It appears that some lithounits previously considered as unique in the Paris Basin (e.g. lignite, plastic clay, fluvial sand, lacustrine limestone and lagoonal sediments) are not synchronous and cannot be regarded as stratigraphic markers for a unique event. This work has been funded by the Regolith and RGF programs of the BRGM, the French Research and Higher Education Ministry and the Belgian AFICI 08-1911 and BR/121/A3/PALEURAFRICA projects.

Leatherbacks constitute a bizarre clade of marine turtles today represented by a single species, Dermochelys coriacea. A series of peculiar physiological adaptations and behaviors make this species particularly reminiscent to some marine mammals. These include particularly advanced skeleton adaptations for swimming, the largest body size among living reptiles, highly elevated growth and metabolic rates, and coldwater tolerance, which enable D. coriacea to lead a truly pelagic, highly migratory, cosmopolitan lifestyle. It is one of the deepest diving animal today, which aids searching for its almost exclusive prey of jellyfishes. Due to their pelagic lifestyle and reduced skeleton, however, the fossil record of leatherbacks is very poor. Here we evaluate the skeletal anatomy of Eosphargis gigas from the Ypresian of Belgium, represented by one of the earliest and most completely preserved fossil dermochelyid. E. gigas already shows several of the anatomical specializations of the extant leatherback but it is primitive in retaining a more ossified shell. The autapomorphic rugose surface decoration of the dermal skull indicates high degree of vascularization, which in turn likely aided regulation of acid–base balance relating to hypercapnia (excess blood carbon dioxide) and/or lactate acidosis based on modern and fossil analogies. Both type of acidosis typically occurs during diving and thus E. gigas likely had deep diving capabilities, which is consistent with its postcranial skeleton. The jaw apparatus also shares many specializations with D. coriacea that may represent adaptation for preying on jellyfish. The emerging hypothesis is that the skeletal and physiological adaptations of leatherbacks are all related to feeding specializations and associated deep diving. Many of these evolved early in the lineage under greenhouse climatic conditions with the likely associated deeper placement of the gelatinous plankton zone compared to icehouse conditions. This study was supported by the SYNTHESYS program (grants AT-TAF 1441, FR-TAF 4290, GB-TAF 1882, BE-TAF 5292); Train2Move-Marie Curie Fellowship awarded to M.R.

A new artiodactyl of moderate size is described on the basis of several dentaries and maxillae from the middle Eocene Subathu Group of the Kalakot area, Rajouri District, Jammu and Kashmir, India. Despite its general resemblance with the family Dichobunidae this taxon shares with Raoellidae two unambiguous characters: the presence of a hypoconulid on p4, and an asymmetrical P4. The position of the new taxon within the Cetacea / Raoellidae clade is strongly supported by eight non ambiguous synapomorphies, among which a cristid obliqua on lower molars anteriorly pointing towards the postectoprotocristid, and a P3 with only two roots. The new taxon is characterised by the following characters: a long symphysis; p3 and p4 with small parastylid and metastylid but no metaconid; lower molars with metaconid as the highest cusp, voluminous hypoconid, and absence of ‘hypolophid’; m1 and m2 with small paraconid, basally fused with metaconid, and small bifid tubercle-like hypoconulid; m3 with a crestiform paraconid; P3 and P4 with small protocone and shelf-like cingulae; upper molars with small paraconule and large metaconule (pseudohypocone); M1 and M2 with conical brachydont cusps; M3 with bunodont bulbous cusps; cristae and cingulae distinct and thick, presence of an ectoloph. The presence of a new primitive raoellid in the middle Eocene Subathu Group sheds new light on the phylogeny and paleobiogeography of basal raoellid artiodactyls. This work is partly funded by project BR/121/A3/PALEURAFRICA from the Belgian Science Policy Office.

X-ray computed tomography (CT-) scanning is revolutionizing the study of extinct organisms. Its non-invasive and non-destructive character makes it currently by far the most potent method to allow fossils to be studied in three dimensions and with unprecedented detail. More importantly, and differing from other 3D techniques, CT-scanning looks through and inside objects, revealing hidden structures and characters. Recent innovations in the field of CT-scanning allow obtaining details up to a few micrometers in resolution, and higher quality images of relatively dense materials, like fossils, even when wholly encased in hard sediment (Keklikoglou et al., 2019). In 2016, the Royal Belgian Institute of Natural Sciences (RBINS) acquired two high-end X-ray CT machines: the micro-CT RX EasyTom and the nano-CT XRE-Tescan UniTom. Both scanners are currently nearly full time in use to help accomplishing the gigantic task of the digitization of the RBINS and Royal Museum for Central Africa (RMCA) type collections, the aim of two multi-year Belspo funded projects, DiSSCo-Fed (2018-2023) and DIGIT-4 (2019-2024). With about 300.000 types and 48.000.000 general specimens, 46.000 and 3.000.000 respectively in their paleontology collections, the results of nearly two centuries of intensive collecting and research, these two Belgian Federal Scientific Institutions (FSI’s) are major players in the European framework of scientific research infrastructures for natural history. Digitizing this large number of types, spread across almost the entire Tree of Life, and exhibiting an entire array of differing taphonomies, results in a steadily growing expertise of the RBINS-RMCA micro-CT lab (Brecko et al., 2018). While the newly acquired infrastructure and ongoing digitization projects are primarily oriented towards the digitization of type and figured specimens, these also offer great opportunities for researchers and teachers in various disciplines of paleontology. Targeting on researchers interested in incorporating micro-CT as a technique in their research projects, the current digitization workflow of the RBINS-RMCA micro-CT lab will be presented. While micro-CT offers many advantages, there are also pitfalls and limitations that need to be considered. Based on our expertise, and illustrated by some of our scanning results, important constraints that may block the pathway between your expectations and perfect micro-CT-imaging results that can be fully incorporated into research projects will be presented. Possible effects of some of the most important parameters that may influence the quality of the output, and thus can increase the signal to noise ratio (SNR) will be reviewed, such as the size and shape of the specimen to be scanned, the density of its matrix the specimen is made of or encased in, the presence of certain minerals (e.g. pyrite) and how these may be distributed inside the specimen (e.g. finely disseminated, dense masses or crystals), the best possible resolution in relation to the specimen and preferred output, the time needed to scan a specimen, the choice between machines to be used and their limits and different possible scan settings (e.g. beam power, filters…). Post-processing parameters to be considered are the size of the image stack output (will the computer be able to handle the amount of Gigabytes?), the time needed to render and segment regions of interest and optimize 3D-models, and which format suits best to visualize and export the data (renderings, meshes, videos, virtual sections…). While segmentation may be a time-consuming task, new developments like the incorporation of artificial intelligence (e.g. the Deep Learning function in Dragonfly ORS) offer great potential to reduce the workload in complex segmentation. Many researchers are also teachers. The reason why they may also be particularly interested in the 3D models of the already digitized types that are available on the Virtual Collections platforms of the RBINS (http://virtualcollections.naturalsciences.be/) and RMCA (https://virtualcol.africamuseum.be/). While 3D models are not intended to replace physical specimens, they may become significant teaching aids in both the physical and virtual classroom. In addition, the presence of a steadily growing number of 3D-models and animations of extant animals that are also added to these Virtual Collections, would allow teachers to connect fossils (in general incomplete) with extant (more complete) relatives. Last but not least, while the focus of this communication is largely on micro-CT, some of the many other new techniques that are being tested, used and improved will be highlighted (see e.g. Brecko & Mathys, 2020; Brecko et al., 2014, 2016, 2018; Mathys et al., 2013, 2019 for some examples). Interested in our work, expertise, techniques, equipment, or scans-on-demand? Please do not hesitate to reach out! References Brecko, J., Lefevre, U., Locatelli, C., Van de Gehuchte, E., Van Noten, K., Mathys, A., De Ceukelaire, M., Dekoninck, W., Folie, A., Pauwels, O., Samyn, Y., Meirte, D., Vandenspiegel, D. & Semal, P. 2018. Rediscovering the museum’s treasures: μCT digitisation of the type collection. Poster presented at 6th annual Tomography for Scientific Advancement (ToScA) symposium, Warwick, England, 10-12 Sept 2018. Brecko, J. & Mathys, A., 2020. Handbook of best practice and standards for 2D+ and 3D imaging of natural history collections. European Journal of Taxonomy, 623, 1-115. Brecko, J., Mathys, A., Dekoninck, W., De Ceukelaire, M., VandenSpiegel, D. & Semal, P., 2016. Revealing Invisible Beauty, Ultra Detailed: The Influence of Low-Cost UV Exposure on Natural History Specimens in 2D+ Digitization. PLoS One 11(8):e0161572. Brecko, J., Mathys, A., Dekoninck, W., Leponce, M., Vanden Spiegel, D. & Semal, P., 2014. Focus stacking: Comparing commercial top-end set-ups with a semi-automatic low budget approach. A possible solution for mass digitization of type specimens. Zookeys, 464, 1-23. Keklikoglou, K., Faulwetter, S., Chatzinikolaou, E., Wils, P., Brecko, J., Kvaček, J., Metscher, B. & Arvanitidis, C. 2019. Micro-computed tomography for natural history specimens: a handbook of best practice protocols. European Journal of Taxonomy, 522, 1-55. Mathys, A., Semal, P., Brecko, J. & Van den Spiegel, D., 2019. Improving 3D photogrammetry models through spectral imaging: Tooth enamel as a case study. PLoS One, 14(8): e0220949. Mathys, A., Brecko, J., Di Modica, K., Abrams, G., Bonjean, D. & Semal, P., 2013. Agora 3D. Low cost 3D imaging: a first look for field archaeology. Notae Praehistoricae, 33/2013, 33-42.

he 2016 Arctic Observing Summit Conference Statement (www.arcticobservingsummit.org) confirms the need for continued development of a globally connected data and information system of systems. Following on developments during the IPY and further evolved over a series of workshops and publications, the polar data community has been working together towards practical, useful, stable, and interoperable infrastructures to support Arctic research and communities. The Arctic community identified interoperability as a foundational goal and theme. Interoperability can be defined as properties of data and information systems that allow them to connect to, and share with, other information products or systems in the present or future without unintended restrictions. However, interoperability is far more than an exercise in engineering. A truly interoperable, globally connected polar data system is a socio-technical system that crosses many scales and knowledge domains. Although developing an interoperable system is complex and challenging, significant progress is being made. In November of 2016, 60 representatives from 17 countries and more than 15 polar data organizations and initiatives participated in the Polar Connections Interoperability Workshop. Based on a pre-workshop analysis and survey, several themes were used to organize the meeting activities: Data discovery and services. Representing Indigenous Knowledge, Community Based Monitoring, and the social sciences. Virtual Research Environments and Cloud computing. Governance and sustainability. Capacity building (cross-cutting). During the workshop, participants. Recognized that many remaining challenges are social rather than technical, such as supporting human networks, promoting standards, and aligning policy with implementation; Confirmed the need for interoperable, federated data discovery and identified existing systems to address this need; Identified key data services and models in support of priority goals; Enhanced models for engaging Indigenous people(s); Initiated connections to global data and information communities for broader interoperability and engagement, including RDA, ESA, and others. We conclude by summarizing outcomes to date, benefits to researchers and communities and proposing next steps.

A number of recent conferences, workshops and meetings have confirmed that there are many national, regional and local projects and programs that are active in polar data mana - gement and stewardship and also have a mandate or desire to contribute to regional or international coordination of effort and activities. Many of those initiatives have resources available and are making progress towards an envisioned connected, interoperable polar data system. The international polar data community is eager to improve cooperation and coordination of their efforts. In the spring of 2018, representatives from a wide range of different active programs and projects will come together to focus on work planning and coordination of effort. This meeting will complement past workshops and fora (e.g. IPY, Polar Data Forums etc.) that have been effective in defining important community challenges and technical issues. The focus of the planned meeting will be to generate detailed plans on how best to mobilise existing and soon-to-be initiated funded activities to develop a particular international data sharing case study. At the annual meetings of the Arctic Data Committee and the Standing Committee on Antarctic Data Management held in Montreal in September 2017, a focus on the sharing of meteorological observations and linking to existing terrestrial data networks was discussed as one possibility. Discussions on the precise nature of the case study will continue, a decision will be taken during the fall of 2017 and it will be reported in this paper. The meeting will be co-led and co-organized by key polar data projects and programs. As of writing, organizers include: IASC/SAON Arctic data Committee; SCAR Standing Committee on Antarctic Data Management; Southern Ocean Observing System; Global Cryosphere Watch and related WMO activities; Polar View; Arctic Spatial Data Infrastructure; EU Arctic Cluster including 8 current EU funded projects; GEO Cold Regions Initiative; Canadian Polar Data Workshop Network; Canadian Consortium on Arctic Data Interoperability; representatives from the Arctic Social Science Community; Research Data Alliance. One International Indigenous organization was part of the initial conceptualization of project in June of 2017 and more input is needed and is actively being sought from Indigenous organizations. In this presentation we report details of the planning process, the established case study, possible inte roperability mechanisms and a discussion of the collaborative process involved in bringing together data stewards from around the Arctic, Antarctica and beyond.