S'escanejen les icnites fòssils de dinosaures més espectaculars

Investigadors de l'Institut Català de Paleontologia (Universitat Autònoma de Barcelona i Generalitat de Catalunya) i de la Universitat de Manchester recorren la Península Ibèrica per escanejar i documentar les icnites fòssils de dinosaures més espectaculars.Investigadores del Institut Català de Paleontologia (UAB y Generalitat de Catalunya) y de la Universidad de Manchester recorren la Península Ibérica para escanear y documentar las icnitas fósiles de dinosaurios más espectaculares.Researchers at the Catalan Institute of Palaeontology (Universitat Autònoma de Barcelona and the Catalan Government) and the University of Manchester have travelled around Spain and Portugal to scan and document the best preserved dinosaur trace fossils

Reconstruint l'estil de vida d'una tortuga extingida

Els investigadors Josep Marmi, Bernat Vila i Àngel Galobart, de l'Institut Català de Paleontologia (ICP-UAB), han aportat noves dades sobre el possible estil de vida de les tortugues del gènere Solemys, que es van extingir a finals del Mesozoic, fa 65 milions d'anys. L'estudi ha estat publicat a la revista "Cretaceous Research" i suggereix que aquestes tortugues podien haver viscut en ambients aquàtics propers al mar.Los investigadores Josep Marmi, Bernat Vila y Àngel Galobart, del Institut Català de Paleontologia (ICP-UAB), han aportado nuevos datos sobre el posible estilo de vida de las tortugas del género Solemys, que se extinguieron a finales del Mesozoico, hace 65 millones de años. El estudio ha sido publicado en la revista "Cretaceous Research" y sugiere que estas tortugas podían haber vivido en ambientes acuáticos próximos al mar

Ichnological evidence of Megalosaurid Dinosaurs crossing Middle Jurassic tidal flats

A new dinosaur tracksite in the Vale de Meios quarry (Serra de Aire Formation, Bathonian, Portugal) preserves more than 700 theropod tracks. They are organized in at least 80 unidirectional trackways arranged in a bimodal orientation pattern (W/NW and E/SE). Quantitative and qualitative comparisons reveal that the large tridactyl, elongated and asymmetric tracks resemble the typical Late JurassicEarly Cretaceous Megalosauripus ichnogenus in all morphometric parameters. Few of the numerous tracks are preserved as elite tracks while the rest are preserved as different gradients of modified true tracks according to water content, erosive factors, radial fractures and internal overtrack formations. Taphonomical determinations are consistent with paleoenvironmental observations that indicate an inter-tidal flat located at the margin of a coastal barrier. The Megalosauripus tracks represent the oldest occurrence of this ichnotaxon and are attributed to large megalosaurid dinosaurs. Their occurrence in Vale de Meios tidal flat represents the unique paleoethological evidence of megalosaurids moving towards the lagoon, most likley during the low tide periods with feeding purposes

Discriminating between medium-sized tridactyl trackmakers : tracking ornithopod tracks in the base of the Cretaceous (Berriasian, Spain)

Background: Recent work on the Jurassic-Cretaceous transition of the Iberian Range (Spain) has opened a new window onto the interpretation of the trackmakers of some medium-sized tridactyl tracks. The ichnotaxon Therangospodus oncalensis has been described in the Huérteles Formation (Berriasian) and is one of the classical tracks from the area assigned to medium-sized theropods. - Methodology/Principal Findings: A review of the type locality of Therangospodus oncalensis (Fuentesalvo tracksite) and other tracksites from the Huérteles Formation (Berriasian) has yielded new information on the morphology, gait and trackmaker identity of the aforementioned ichnospecies. The new data suggest that the trackmaker is an ornithopod rather than a theropod on the basis of the length/width ratio, the anterior triangle lengthwidth ratio, the short steps, the round to quadrangular heel pad impression and the probable manus impressions. - Conclusions/Significance: T. oncalensis shows similarities with various tracks from the Berriasian of Europe assigned to Iguanodontipus. The ichnotaxonomical status of this ichnospecies is here considered as Iguanodontipus? oncalensis due to the current state of knowledge of the ichnotaxonomy of medium-sized ornithopod tracks. This reassessment of I? oncalensis also has two significant implications for the palaeoecology of the faunas during the deposition of the Huérteles Formation: 1- the high number and percentage of theropod tracks would be lower than previous papers have suggested. 2- the gregarious behaviour described in the type locality (Fuentesalvo) would be among ornithopods instead of theropods

Los saurópodos del Cretácico superior del sur de Europa : diversidad, icnología y biología reproductiva

Tesis Doctoral inédita leída en la Universidad Autónoma de Madrid, Facultad de Ciencias, Departamento de Biología. Fecha de lectura: 18-06-201

Evidence of reproductive stress in Titanosaurian Sauropods triggered by an increase in ecological competition

The occurrence of dinosaur pathologic eggs in the Late Cretaceous of Europe is well known, but their origin remains unclear. Here we expose the results of a detailed sampling of the conspicuous fossil record of Late Cretaceous titanosaurian eggs (oogenus Megaloolithius) from several southwestern Europe basins. After examining more than 450 samples, we observed a remarkable and statistically supported occurrence of multiple pathologic eggs in a relatively short stratigraphic range at the end of the early Maastrichtian, circa 71-70Ma. All pathologic specimens exhibit multi-layered eggshell condition, a characteristic related to dystocia, or egg retention within the female uterus for an abnormal prolonged period of time. After exploring various scenarios, the occurrence of pathologic eggs is strongly correlated with an intense dinosaur faunal replacement that occurred during the early Maastrichtian in the Ibero-Armorican Island. Given that inter-species competiveness is proved to produce major affects in ecological communities, our results suggest that pathologies in the eggs of European titanosaurians could be a consequence of an increase in reproductive stress triggered by direct ecological competition between different dinosaurs. Thus, the present study provides a new perspective of how dinosaurs might have been affected by ecological/environmental disturbance