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Caverne X in Waulsort (Namur province, Belgium), excavated in the 19 th century, revealed a burial site which was unexpectedly dated to the Final Upper Paleolithic (10,820 ± 80 BP, OxA-6856) in the 1990's. A re-examination of the collection and a new radiocarbon dating program was recently undertaken. The dates obtained on four left femurs (9285 ± 30 BP, ETH-74725; 9310 ± 30 BP, ETH-74726; 9340 ± 30 BP, ETH-74727; 9300 ± 30 BP, ETH-74728) revealed that the remains should in fact be attributed to the Early Mesolithic, ISSN 0259-3548 25 MM 28:2 (December 2020) consistent with 24 other 14 C dates obtained for eight cave sites in the Meuse Basin which range from ca. 9600 BP to 9000 BP. Caverne X contained 544 human remains belonging to at least nine individuals (one fetus, one perinatal/young child, one teenager, two adolescents/young adults and four adults), and 66 faunal remains consisting mainly of intrusive animals with the possible exception of a cervid antler, and one artefact (a small flint blade). Other than ochre deposits, all alterations (breakage, surface abrasion, impact scars and concretions) are post-depositional in origin. Carbon and nitrogen stable isotope analysis indicates a diet primarily based on terrestrial resources from an open landscape with proteins provided by large herbivores. Our study shows that Caverne X fits well with results already obtained for the Meuse Basin cave burials in terms of chronology, minimum number of individuals, funerary rituals and diet.

Premise of research. Although the most comprehensively known Devonian seeds were borne in a “telomic” cupule, those of some species have been postulated as being borne terminally on naked axes lacking a cupule. Uncertainty remains as to whether such seeds were shed from a cupule before preservation. We reinvestigate the Upper Devonian fossils Pseudosporogonites hallei and Xenotheca bertrandii from Belgium and the similar ovules Aglosperma quadrapartita and Aglosperma avonensis from Britain and Aglosperma sp. from North America to consider their structure and organization and to determine whether they were cupulate. Methodology. Compressions/adpressions of X. bertrandii and Pseudosporogonites from Belgium and A. quadrapartita and A. avonensis from the United Kingdom, as well as Anglosperma sp. from Pennsylvania, were prepared, mainly by dégagement. Observation and photography were carried out using crossed polarizing filters. Pivotal results. Pseudosporogonites hallei, X. bertrandii, and A. quadrapartita comprise single ovules borne within small, radially symmetrical, uniovulate cupules. Integuments are entire at the chalaza but form flattened lobes distally. While a cupule is unknown in A. avonensis, its comparable integument morphology suggests that it was shed from a uniovulate cupule. Although the species are distinct from each other, their similarities show that they are closely related and belong to a single genus, for which the name Pseudosporogonites has priority. We emend P. hallei in light of our findings and erect the combinations P. bertrandii (Stockmans) C. Prestianni, J. Hilton et W. Cressler, P. quadrapartitus (J. Hilton et D. Edwards) C. Prestianni, J. Hilton et W. Cressler, and P. avonensis (J. Hilton) C. Prestianni, J. Hilton et W. Cressler. Conclusions. The uniovulate cupule in Pseudosporogonites is distinct from multiovulate telomic cupules of other Devonian seeds and expands the phenotypic diversity seen during the earliest phase of seed plant radiation, which was geologically instantaneous. Hydrasperman pollination in all proven Devonian seeds demonstrates evolution from a common ancestor, but finding morphological intermediates between seed and free-sporing plants remains a significant challenge to evolutionary plant biology.

Talk presented by Stijn Goolaerts on 09/09/2012 in session 10: Nautilids of the 9th ISCPP in Zurich, Switzerland

Subsistence strategies are key paleoecological features of Paleolithic hunter-gatherers and their deeper understanding provides crit- ical insights into essential aspects of human evolution. In this study, we discuss new collagen stable isotopic values (C, N, S) rep- resenting seven Gravettian individuals from the Troisième caverne of Goyet in Belgium. The dietary strategies of the Gravettian humans from Goyet are in line with the general trends observed among Western European Gravettian populations. These pop- ulations show both a low intake of mammoth and a high consumption of other terrestrial mammals as well as aquatic resources, such as at the sites Arene Candide and La Rochette. This is different for more eastern Gravettian hunter-gatherers, for example in Kostenki, Brno-Francouzska, Mal’ta, Předmostí, and Dolní Věstonice where the dietary contribution of mammoth meat was sig- nificantly higher. The stable isotopic data of the Gravettian humans from Goyet indicate that their dietary ecology was essentially based on terrestrial resources like reindeer, horse, and, to a lesser extent, mammoth. However, they yielded δ15N values that are substantially lower than those of the earlier modern humans and Neandertals from the same site [1-2]. We hypothesize that the Gravettian humans had much less mammoth in their diet than all earlier humans from the same region. It was previously shown that in northwestern Europe a decline of mammoth, a key prey species, could already be detected at the onset of the Upper Paleolithic [2]. This trend appears to continue into the Gravettian, despite the persistence of the typical mammoth ecological niche, which is represented by a grassland with high δ15N values. Interestingly, through isotopic analysis, we are able to track the spread of the horse from the local ecosystem (represented by specimens from Walou Cave, Belgium) into this niche now under-occupied by the mammoth. Radiocarbon dates obtained from several mammoth skeletal remains from the Troisième caverne of Goyet showed that this megaherbivore was indeed part of the ecosystem during pre-LGM periods. However, from the Gravettian in Goyet and the surrounding region we have only one mammoth specimen represented by a long bone, and interestingly, its sulphur isotopic signal indicates that this individual was not of local origin. We propose that the local mammoth population was under intensive hunting pressure or may even have been no longer present in the region. Instead, single individuals from other regions may have made it into the area and ended up as prey animals. While the δ15N values of all Goyet Gravettian humans are relatively homogeneous, their δ13C values are variable. This indicates significant dietary differences among the seven individuals, an observation that has not been described before for hunter-gatherers pre-dating the Gravettian. The human δ34S values also support substantial differences in life mobility history between different individuals, which were not observed for the Goyet Neandertals. The result that different mem- bers of the same chrono-group had various individual mobility histories has implications for land use procurement strategies of those hunter-gatherer groups. In conclusion, our new isotopic results demonstrate a broad ecological flexibility among Gravettian humans, which can be seen in different human ecosystem interactions across Europe. The Goyet individuals contribute substan- tially to a more complete understanding of hunter-gatherer’s ecology during this particular phase of the European Late Pleistocene. Our study shows that the Gravettian cannot be depicted as a uniform entity from an ecological perspective. It instead indicates that during this period, and not earlier, both inter- and intra-group diversity in subsistence strategies can be tracked through stable isotopic analysis.

Evolution may improve the invasiveness of populations, but it often remains unclear whether key adaptation events occur after introduction into the recipient habitat (i.e. post-introduction adaptation scenario), or before introduction within the native range (i.e. prior-adaptation scenario) or at a primary site of invasion (i.e. bridgehead scenario). We used a multidisciplinary approach to determine which of these three scenarios underlies the invasion of the tropical ant Wasmannia auropunctata in a Mediterranean region (i.e. Israel). Species distribution models (SDM), phylogeographical analyses at a broad geographical scale and laboratory experiments on appropriate native and invasive populations indicated that Israeli populations followed an invasion scenario in which adaptation to cold occurred at the southern limit of the native range before dispersal to Israel. We discuss the usefulness of combining SDM, genetic and experimental approaches for unambiguous determination of eco-evolutionary invasion scenarios.

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.