Rosegadors prehistòrics del desert, creuant a peu el Mediterrani

Fa aproximadament sis milions d'anys, el mar Mediterrani es va assecar gairebé completament en el que es coneix com a "Crisi de Salinitat del Messinià", a causa del tancament de la connexió entre l'Atlàntic i el Mediterrani. Això va permetre l'aparició de zones transitables per a animals terrestres que van poder arribar a la Península Ibèrica des del Nord d'Àfrica a finals del Miocè. Investigadors del ICP han descobert, per primera vegada a Europa, fòssils del rosegador Myocricetodon jaegeri en el jaciment de Negratín-1 (Guadix). Aquest descobriment confirma la hipòtesi que suposa que certs gèneres de mamífers van arribar a la Península Ibèrica creuant un desertitzat estret de Gibraltar.Hace aproximadamente seis millones de años, el mar Mediterráneo se secó casi completamente en lo que se conoce como "Crisis de Salinidad del Messiniense", debido al cierre de la conexión entre el Atlántico y el Mediterráneo. Esto permitió la aparición de zonas transitables para animales terrestres que pudieron llegar a la Península Ibérica desde el Norte de África a finales del Mioceno. Investigadores del ICP han descubierto, por primera vez en Europa, fósiles del roedor Myocricetodon jaegeri en el yacimiento de Negratín-1 (Guadix). Este descubrimiento confirma la hipótesis que supone que ciertos géneros de mamíferos llegaron a la Península Ibérica cruzando un desertizado estrecho de Gibraltar

A new primate assemblage from La Verrerie de Roches (Middle Eocene, Switzerland)

Primates reached a great abundance and diversity during the Eocene, favored by warm temperatures and by the development of dense forests throughout the Northern Hemisphere. Here we describe new primate material from La Verrerie de Roches, a Middle Eocene karstic infill situated in the Jura Region (Switzerland), consisting of more than 80 dental remains. The primate assemblage from La Verrerie de Roches includes five different taxa. The best represented primate is Necrolemur aff. anadoni, similar in size and overall morphology to Necrolemur anadoni but resembling in some features the younger species Necrolemur antiquus. Microchoerines are also represented by two species of Pseudoloris, P. pyrenaicus and Pseudoloris parvulus, constituting the unique joint record of these two species known up to now. Remains of Adapiformes are limited to one isolated tooth of a large anchomomyin and another tooth belonging to the small adapine Microadapis cf. sciureus. The studied primate association allows assigning La Verrerie de Roches to the Robiacian Land Mammal Age. More specifically, this site can be confidently situated between the MP15 and MP16 reference levels, although the primate assemblage probably indicates some degree of temporal mixing. This is the first record of P. pyrenaicus and a form closely related to N. anadoni out of the Iberian Peninsula. The identification of these microchoerines in Switzerland gives further support to the connection of NE Spain and Central Europe during the Middle Eocene

Agerinia marandati sp. nov., a new early Eocene primate from the Iberian Peninsula, sheds new light on the evolution of the genus Agerinia

Background. The Eocene was the warmest epoch of the Cenozoic and recorded the appearance of several orders of modern mammals, including the first occurrence of Euprimates. During the Eocene, Euprimates were mainly represented by two groups, adapiforms and omomyiforms, which reached great abundance and diversity in the Northern Hemisphere. Despite this relative abundance, the record of early Eocene primates from the European continent is still scarce and poorly known, preventing the observation of clear morphological trends in the evolution of the group and the establishment of phylogenetic relationships among different lineages. However, knowledge about the early Eocene primates from the Iberian Peninsula has been recently increased through the description of new material of the genus Agerinia from several fossil sites from Northeastern Spain. - Methods. Here we present the first detailed study of the euprimate material from the locality of Masia de l'Hereuet (early Eocene, NE Spain). The described remains consist of one fragment of mandible and 15 isolated teeth. This work provides detailed descriptions, accurate measurements, high-resolution figures and thorough comparisons with other species of Agerinia as well with other Eurasian notharctids. Furthermore, the position of the different species of Agerinia has been tested with two phylogenetic analyses. - Results. The new material from Masia de l'Hereuet shows several traits that were previously unknown for the genus Agerinia, such as the morphology of the upper and lower fourth deciduous premolars and the P2, and the unfused mandible. Moreover, this material clearly differs from the other described species of Agerinia, A. roselli and A. smithorum, thus allowing the erection of the new species Agerinia marandati. The phylogenetic analyses place the three species of Agerinia in a single clade, in which A. smithorum is the most primitive species of this genus. - Discussion. The morphology of the upper molars reinforces the distinction of Agerinia from other notharctids like Periconodon. The analysis of the three described species of the genus, A. smithorum, A. marandati and A. roselli, reveals a progressive change in several morphological traits such as the number of roots and the position of the P1 and P2, the molarization of the P4, the reduction of the paraconid on the lower molars and the displacement of the mental foramina. These gradual modifications allow for the interpretation that these three species, described from the early Eocene of the Iberian Peninsula, are part of a single evolutionary lineage. The stratigraphical position of Masia de l'Hereuet and Casa Retjo-1 (type locality of A. smithorum) and the phylogenetic analyses developed in this work support this hypothesis

New dental material and redescription of Agerinia roselli (Primates, Adapiformes) from Les Saleres (early Eocene, NE Iberian Peninsula)

In this work, new dental material of Agerinia roselli from its type locality, Les Saleres (NE Spain), is described. An emended diagnosis of the species is provided, together with a redescription of the entire hypodigm from that locality, which was necessary due to some inaccuracies in previous descriptions. The studied material includes 12 teeth (from P3 to M3); the roots of the anterior premolars preserved in a mandible fragment are reported for the first time. Some previously undescribed traits have been identified after the new analysis of this material, such as the P4 with distinct hypoconid and entoconid and the tiny paraconid on the M1. A detailed comparison with other cercamoniines has been made. The body mass of A. roselli, ranging from 650 to 900 g, has also been estimated. The presence of a minuscule paraconid in the M1 is the most reliable criterion for distinguishing this molar from the M2. This is supported by the complete absence of paraconid in four M2 preserved in mandible fragments. The trigonid length seems to be less reliable for distinguishing M1 from M2, due to its high variability in this species. Concluding, this study updates the knowledge about the dental anatomy of A. roselli and demonstrates that it is a valid taxon clearly distinguishable from other cercamoniines

Evolución de las asociaciones de insectívoros (Eulipotyphla, Mammalia) en España y su relación con los cambios climáticos del Neógeno y el Cuaternario

El conocimiento del registro fósil ibérico neógeno y cuaternario de los insectívoros, el grupo de pequeños mamíferos incluidos en el orden Eulipotyphla, ha experimentado una notable mejora en las últimas dos décadas. Este avance, unido a un refinamiento en la datación de muchos yacimientos españoles, permite hacer un seguimiento de la evolución de las comunidades de insectívoros a lo largo de los últimos 20 millones de años, hasta llegar a la configuración actual. Dada la sensibilidad de estas especies a ciertas condiciones ambientales, y en el contexto geográfico ibérico, los cambios en la diversidad de insectívoros a nivel genérico en el registro fósil español pueden ser relacionados con algunos eventos biológicos y con las tendencias climáticas a gran escala en el hemisferio norte.The knowledge of the Neogene and Quaternary fossil record of the insectivores, the small mammals included in the order Eulipotyphla, has been greatly improved in the last two decades. This improvement, linked to a refinement on the dating of many Spanish fossil localities, allows tracking the evolution of the insectivore assemblages during the last 20 million years leading to the Recent communities. Given the sensitivity of these species to certain environmental conditions within the Iberian geographic context, the changes on the insectivore diversity at generic level can be confidently associated to some biological events and linked to the large-scale climatic trends in the Northern Hemisphere.Agencia Estatal de Investigación (AEI) de España y el European Regional Development Fund de la Unión Europea (MINECO/FEDER, UE) mediante los proyectos CGL2015-63777-P, CGL2016-76431-P, CGL2016-80000-P y CGL2017-82654-P Además, M.F., J.A. y R.M.- B. han contado con la ayuda de la Generalitat de Catalunya (Programa CERCA)

Repli-Fósil-3D: Aplicación técnicas de replicación 3D para la mejora de las colecciones utilizadas en la docencia práctica del área de Paleontología

En este proyecto se ha pretendido perfeccionar la docencia práctica de las asignaturas del ámbito de la Paleontología y de las actividades divulgativas impartidas por el departamento de Estratigrafía y Paleontología, y por lo tanto mejorar el grado de aprendizaje del alumnado, mediante el uso de modelos y réplicas impresas en 3D de diferentes grupos fósiles que, por diversos motivos (escasez de muestras en nuestros laboratorios, tamaño o fragilidad), no pueden ser correctamente observados y/o manipulados por el alumnado. Esto ha permitido al profesorado del área de Paleontología adaptar las prácticas docentes y actividades divulgativas a los requerimientos de la sociedad y universidad actuales.The aim of this project has been to improve the practical teaching of subjects in the field of Paleontology and in other dissemination activities carried out by the Department of Stratigraphy and Paleontology, in order to enhance the student learning. To do so, this project printed 3D models and replicas of different fossil groups which, for various reasons (scarcity of samples in our laboratories, size or fragility), cannot be correctly observed and/or manipulated by students. This has allowed the teaching staff of the Paleontology area to adapt their teaching practices and dissemination activities to the requirements of today's society and university