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Computational fluid dynamics as a tool for testing functional and ecological hypotheses in fossil taxa

Computational fluid dynamics is a method for simulating fluid flows that has been widely used in engineering for decades, and which also has applications for studying function and ecology in fossil taxa. However, despite the possible benefits of this approach, computational fluid dynamics has been used only rarely in palaeontology to date. The theoretical basis underlying the technique is outlined and the main steps involved in carrying out computer simulations of fluid flows are detailed.

Carnivoran resource and habitat use in the context of a Late Miocene faunal turnover episode

We investigate resource and habitat use by apex predators through stable isotope analysis at two Spanish Late Miocene localities: Los Valles de Fuentidueña (~9.6 Ma, LVF) and Cerro de los Batallones (~9.1 Ma, BAT). The temporal window represented by LVF and BAT was crucial in the shaping of the current Iberian mammalian structure because it corresponds to the initial stages of a faunal turnover episode and regional environmental change at ~9.5–8.5 Ma (Vallesian–Turolian transition), associated with an increase in the seasonality of precipitation.

Non‐traditional isotope perspectives in vertebrate palaeobiology

The recent development of multi‐collector inductively coupled plasma mass spectrometry (MC‐ICP‐MS) notably in the disciplines of earth sciences, now allows the precise measurement of isotope ratios, even at low concentration. Non‐traditional isotope systems, such as alkaline earth (Ca, Mg) and transition (Cu, Fe, Zn) metals are now being measured in a variety of biological tissues, including bone and teeth.

Observations of the structural changes that occur during charcoalification: implications for identifying charcoal in the fossil record

All of our current understanding of fossil charcoal structure comes from observations of modern wood charcoal produced in furnaces. These charcoals consistently show cell wall homogenization after prolonged heating (>325°C) and this is therefore considered to be a key identifying feature of fossil charcoal. Yet furnaces are unable to replicate the full combustion processes that occur during a wildfire.

A new scyphozoan from the Cambrian Fortunian Stage of South China

Animals with radial symmetry are abundant in the Cambrian Fortunian Stage of South China, but with relatively low diversity: representatives include Olivooides, Quadrapyrgites, carinachitiids, hexangulaconulariids and Pseudooides. Here, we report a new radial animal, Qinscyphus necopinus gen. et sp. nov., from the Fortunian small shelly fauna of southern Shaanxi Province, South China. Qinscyphus necopinus has a cup‐shaped profile, with slightly raised annuli and five groups of triangular thickenings in pentaradial symmetry.

Climate and sea‐level changes across a shallow marine Cretaceous–Palaeogene boundary succession in Patagonia, Argentina

Upper Maastrichtian to lower Paleocene, coarse‐grained deposits of the Lefipán Formation in Chubut Province, (Patagonia, Argentina) provide an opportunity to study environmental changes across the Cretaceous–Palaeogene (K–Pg) boundary in a shallow marine depositional environment. Marine palynological and organic geochemical analyses were performed on the K–Pg boundary interval of the Lefipán Formation at the San Ramón section. The palynological and organic geochemical records from the San Ramón K–Pg boundary section are characteristic of a highly dynamic, nearshore setting.

Testing hypotheses of element loss and instability in the apparatus composition of complex conodonts: articulated skeletons of Hindeodus

Knowledge of the conodont skeleton, in terms of the morphology of the elements and the positions they occupy, provides the foundation for understanding of homology, taxonomy and evolutionary relationships in conodonts. This knowledge also underpins analyses of conodont functional morphology and feeding.

Protracted growth impedes the detection of sexual dimorphism in non‐avian dinosaurs

Evidence for sexual dimorphism is extremely limited in the non‐avian dinosaurs despite their high diversity and disparity, and despite the fact that dimorphism is very common in vertebrate lineages of all kinds. Using body‐size data from both Alligator mississippiensis and Rhea americana, which phylogenetically bracket the dinosaurs, we demonstrate that even when there is strong dimorphism in a species, random sampling of populations of individuals characterized by sustained periods of growth (as in the alligator and most dinosaurs) can result in the loss of this signal.

Early Middle Ordovician scolecodonts from north‐western Argentina and the emergence of labidognath polychaete jaw apparatuses

Scolecodonts provide fossil evidence of the evolution and diversification of jaw‐bearing polychaetes from the latest Cambrian onwards. However, their record before the Darriwilian (Middle Ordovician) is scarce worldwide, which limits our understanding of key evolutionary events. One such event is the emergence of taxa possessing the asymmetrical labidognath‐type jaw apparatus architecture, which became common in the Middle Ordovician and is often dominant throughout the Palaeozoic.

Low fossilization potential of keratin protein revealed by experimental taphonomy

Recent studies have suggested the presence of keratin in fossils dating back to the Mesozoic. However, ultrastructural studies revealing exposed melanosomes in many fossil keratinous tissues suggest that keratin should rarely, if ever, be preserved. In this study, keratin's stability through diagenesis was tested using microbial decay and maturation experiments on various keratinous structures. The residues were analysed using pyrolysis‐gas chromatography‐mass spectrometry and compared to unpublished feather and hair fossils and published fresh and fossil melanin from squid ink.

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