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A re-examination of the early Toarcian fish fossils preserved in public paleontological collections in Luxembourg revealed 70 specimens of large Toarcian pachycormid fish with an excellent three-dimensional preservation within calcareous nodules. Six of them are associated with octobrachian coleoid gladii in their oesophagus or stomach, an association not previously described from Luxembourg. The pachycormids are ascribed to Pachycormus macropterus (Blainville, 1818) and Saurostomus esocinus Agassiz, 1843 while the octobrachian gladii are ascribed to Teudopsis bollensis Voltz, 1836, Teudopsis sp. indet. and Loligosepiidae indet. The position and orientation of the gladii provide direct evidence of these fishes feeding on coleoids and thus a teuthophagous diet, rather than an accidental joint burial. Together with evidence from coeval deposits in Germany, these findings suggest that teuthophagy was a widespread feeding strategy at the base of the clade that contains the suspension-feeding pachycormid giants of the Jurassic–Cretaceous. [ABSTRACT FROM AUTHOR]

The traditional terminology of ‘scythe’ or ‘sickle’ shaped is observed to be flawed as an effective descriptor for pectoral fin shape in pachycormids. The diversity of pachycormid pectoral fin shapes is assessed across the 14 recognised genera that preserve complete pectoral fins, and improved terms are defined to more effectively describe their form, supported by anatomical observation and aspect ratio analysis of individual fins, and corroborated by landmark analysis. Three clear and distinct pectoral fin structural morphotypes emerge (falceform, gladiform, falcataform), reflecting a diversity of pachycormid lifestyles throughout the Mesozoic, from agile pursuit predator to slow-cruising suspension feeder. [ABSTRACT FROM AUTHOR]

Plesiadapid mammals (Eutheria, Euarchonta, Plesiadapiformes) are well represented in the late Paleocene to early Eocene of Europe (reference levels MP6, MP7 and MP8+9), but relationships among the described species and their links to North American plesiadapids remain disputed. To better understand the evolution of the group in Europe, to explore its potential for biochronological dating and to test hypotheses on plesiadapid phylogenies and dispersal patterns between Europe and North America, a morphometric analysis was performed for a succession of plesiadapid assemblages bracketing the Paleocene/Eocene boundary (PEB) in the Paris Basin, including recently made collections from Montchenot (MP6) and Le Quesnoy (MP7). Both dental size and shape were analysed for nearly all positions of the permanent plesiadapid dentition. Size variation at Cernay (MP6) is consistent with the presence of at least two species of Plesiadapis. A morphological succession is found in European large-sized Plesiadapis, continuing beyond the PEB but showing no clear continuity with Eocene Platychoerops. Large-sized Plesiadapis from Berru (MP6) is distinctly different from P. tricuspidens, justifying the definition of a new species, P. berruensis. Species of Plesiadapis confirm the temporal succession of the localities Cernay, Berru, Le Quesnoy and Meudon, allowing definition of a refined biochronology in the Paris Basin, with Montchenot correlated approximately to Cernay. Comparisons between plesiadapids from Europe and North America indicate a separation from at least the terminal Tiffanian, suggesting correlation of the European reference level MP6 with the North American biozones Ti-5b and Ti-6. Convergent evolution in those lineages and in Platychoerops seems to be linked mainly to trends towards folivory. [ABSTRACT FROM AUTHOR]

Most of the known and most-complete Early Jurassic specimens of plesiosaurians were recovered from the United Kingdom and Germany, and few specimens from that age originate from other areas in Europe. This study describes a new plesiosaurian taxon from Toarcian deposits of Luxembourg, Microcleidus melusinae , represented by the most complete skeleton ever discovered from this country. A preliminary phylogenetic analysis places Microcleidus melusinae within Microcleididae, as a sister taxon of the species previously included in the genus Microcleidus. The new specimen studied here contributes to our understanding of the palaeodiversity of Early Jurassic plesiosaurians and confirms their high degree of 'endemism' and low morphological disparity. [ABSTRACT FROM AUTHOR]

We investigated the contribution of freshwater resources to the diet of seven Late Mesolithic hunter-gatherers (ca. 5300–7000 BC) from Northern France and Luxembourg using stable isotope ratios. In addition to the carbon and nitrogen stable isotope ratios (δ13C, δ15N), we explored the potential of the sulphur isotopic ratios (δ34S) to detect and quantify the proportion of protein derived from aquatic foodstuff. In only two sites, animal remains from an associated settlement were available and subsequently examined to decipher the isotopic differential between terrestrial and freshwater resources. The quantification of their relative contribution was simulated using a Bayesian mixing model. The measurements revealed a significant overlap in δ13C values between freshwater and terrestrial resources and a large range of δ15N values for each food category. The δ34S values of the aquatic and terrestrial animals were clearly distinct at the settlement in the Seine valley, while the results on fish from Belgium demonstrated a possible overlap in δ34S values between freshwater and terrestrial resources. Local freshwater ecosystem likely contributed to ca. 30–40 % of the protein in the diet of the individuals found in the Seine settlement. Out of this context, the isotopic signature and thus contribution of the available aquatic foods was difficult to assess. Another potential source of dietary protein is wild boar. Depending on the local context, collagen δ34S values may contribute to better assessment of the relative contribution of freshwater and terrestrial resources. [ABSTRACT FROM AUTHOR]

We sequenced the genomes of a ∼7,000-year-old farmer from Germany and eight ∼8,000-year-old hunter-gatherers from Luxembourg and Sweden. We analysed these and other ancient genomes with 2,345 contemporary humans to show that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians, who contributed to both Europeans and Near Easterners; and early European farmers, who were mainly of Near Eastern origin but also harboured west European hunter-gatherer related ancestry. We model these populations' deep relationships and show that early European farmers had ∼44% ancestry from a 'basal Eurasian' population that split before the diversification of other non-African lineages. [ABSTRACT FROM AUTHOR]

Early Jurassic belemnites are of particular interest to the study of the evolution of skeletal morphology in Lower Carboniferous to the uppermost Cretaceous belemnoids, because they signal the beginning of a global Jurassic- Cretaceous expansion and diversification of belemnitids. We investigated potentially relevant, to this evolutionary pattern, shell features of Sinemurian- Bajocian Nannobelus, Parapassaloteuthis, Holcobelus and Pachybelemnopsis from the Paris Basin. Our analysis of morphological, ultrastructural and chemical traits of the earliest ontogenetic stages of the shell suggests that modified embryonic shell structure of Early- Middle Jurassic belemnites was a factor in their expansion and colonization of the pelagic zone and resulted in remarkable diversification of belemnites. Innovative traits of the embryonic shell of Sinemurian- Bajocian belemnites include: (1) an inorganic-organic primordial rostrum encapsulating the protoconch and the phragmocone, its non-biomineralized component, possibly chitin, is herein detected for the first time; (2) an organic rich closing membrane which was under formation. It was yet perforated and possessed a foramen; and (3) an organic rich pro-ostracum earlier documented in an embryonic shell of Pliensbachian Passaloteuthis. The inorganic-organic primordial rostrum tightly coating the protoconch and phragmocone supposedly enhanced protection, without increase in shell weight, of the Early Jurassic belemnites against explosion in deep-water environment. This may have increased the depth and temperature ranges of hatching eggs, accelerated the adaptation of hatchlings to a nektonic mode of life and promoted increasing diversity of belemnoids. This study supports the hypothesis that belemnite hatchlings were 'a miniature of the adults'. [ABSTRACT FROM AUTHOR]

A diversified fauna of fossil mammals is described from the Thanetian Marnes de Montchenot near Reims (France, Paris Basin). The new fauna is composed mainly of micromammals, which are represented by isolated teeth and a few more complete dental remains. Multituberculates, insectivore-like mammals and louisinine 'condylarths' are particularly common at Montchenot, and tiny toliapinid plesiadapiforms are relatively well represented. In contrast, the larger-sized plesiadapiform Plesiadapis and pleuraspidotheriid 'condylarths' are less abundant than at Cernay or Berru. Special attention is paid to Neoplagiaulax nicolai, the most common species of multituberculate at Montchenot. The new sample of this species allows to reconsider the composition of its upper premolar series and the orientation of isolated deciduous anterior upper premolars in neoplagiaulacids. Insectivore-like mammals from Montchenot include a previously unrecognised adapisoriculid, known by the complete upper and lower molar series, which combines an Afrodon-like morphology with strong posterior cingula on its upper molars. Mammal fossils indicate an age of the Montchenot fauna close to Cernay (European mammalian reference level MP6), confirming previous age determinations based on mollusks and charophytes. Preservational biases including selective predation and hydrodynamic sorting, possibly in combination with specific palaeoenvironmental conditions related to deposition in a quiet freshwater milieu, seem to be responsible for the peculiar composition of the mammalian fauna from Montchenot compared to other late Paleocene localities in the Paris Basin. [ABSTRACT FROM AUTHOR]

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