Steinmann Institute For Geologie
Steinmann Institute For Geologie
Krogmann L.,Entomologie |
Mayer C.,Center for Molecular Biodiversity Research |
Donath A.,Center for Molecular Biodiversity Research |
Gunkel S.,Steinmann Institute For Geologie |
And 24 more authors.
Current Biology | Year: 2017
Hymenoptera (sawflies, wasps, ants, and bees) are one of four mega-diverse insect orders, comprising more than 153,000 described and possibly up to one million undescribed extant species [1, 2]. As parasitoids, predators, and pollinators, Hymenoptera play a fundamental role in virtually all terrestrial ecosystems and are of substantial economic importance [1, 3]. To understand the diversification and key evolutionary transitions of Hymenoptera, most notably from phytophagy to parasitoidism and predation (and vice versa) and from solitary to eusocial life, we inferred the phylogeny and divergence times of all major lineages of Hymenoptera by analyzing 3,256 protein-coding genes in 173 insect species. Our analyses suggest that extant Hymenoptera started to diversify around 281 million years ago (mya). The primarily ectophytophagous sawflies are found to be monophyletic. The species-rich lineages of parasitoid wasps constitute a monophyletic group as well. The little-known, species-poor Trigonaloidea are identified as the sister group of the stinging wasps (Aculeata). Finally, we located the evolutionary root of bees within the apoid wasp family “Crabronidae.” Our results reveal that the extant sawfly diversity is largely the result of a previously unrecognized major radiation of phytophagous Hymenoptera that did not lead to wood-dwelling and parasitoidism. They also confirm that all primarily parasitoid wasps are descendants of a single endophytic parasitoid ancestor that lived around 247 mya. Our findings provide the basis for a natural classification of Hymenoptera and allow for future comparative analyses of Hymenoptera, including their genomes, morphology, venoms, and parasitoid and eusocial life styles. © 2017 Elsevier Ltd
Rocek Z.,Academy of Sciences of the Czech Republic |
Boistel R.,CNRS Institute of Paleoprimatology, Human Paleontoly: Evolution and Paleoenvironments |
Lenoir N.,French National Center for Scientific Research |
Mazurier A.,CNRS Poitiers Institute of Chemistry: Materials and Natural Resources |
And 6 more authors.
Anatomical Record | Year: 2015
Palaeobatrachidae are extinct frogs from Europe closely related to the Gondwanan Pipidae, which includes Xenopus. Their frontoparietal is a distinctive skeletal element which has served as a basis for establishing the genus Albionbatrachus. Because little was known about developmental and individual variation of the frontoparietal, and its usefulness in delimiting genera and species has sometimes been doubted, we investigate its structure in Palaeobatrachus and Albionbatrachus by means of X-ray high resolution computer tomography (micro-CT). To infer the scope of variation present in the fossil specimens, we also examined developmental and interspecific variation in extant Xenopus. In adults of extinct taxa, the internal structure of the frontoparietal bone consists of a superficial and a basal layer of compact bone, with a middle layer of cancellous bone between them, much as in early amphibians. In Albionbatrachus, the layer of cancellous bone, consisting of small and large cavities, was connected with the dorsal, sculptured surface of the bone by a system of narrow canals; in Palaeobatrachus, the layer of cancellous bone and the canals connecting this layer with the dorsal surface of the frontoparietal were reduced. The situation in Palaeobatrachus robustus from the lower Miocene of France is intermediate-while external features support assignment to Palaeobatrachus, the inner structure is similar to that in Albionbatrachus. It may be hypothesized that sculptured frontoparietals with a well-developed layer of cancellous (i.e., vascularized) bone may indicate adaptation to a more terrestrial way of life, whereas a reduced cancellous layer might indicate a permanent water dweller. © 2015 Wiley Periodicals, Inc.
Soriano C.,European Synchrotron Radiation Facility |
Soriano C.,CNRS Geosciences Laboratory of Rennes |
Archer M.,University of New South Wales |
Azar D.,Lebanese University |
And 15 more authors.
Comptes Rendus - Palevol | Year: 2010
Over the past six years, organic inclusions preserved in amber samples from outcrops worldwide have been discovered and imaged in 3D using propagation phase contrast based X-ray synchrotron imaging techniques at the European Synchrotron Radiation Facility (ESRF). A brief description of the techniques and protocols used for detecting and 3D non-destructive imaging of amber inclusions is provided. The latest results from the major amber projects in the ESRF are given, illustrating the increasing utility of the imaging capabilities of X-ray synchrotron phase contrast microtomography. © 2010 Académie des sciences.
Neumann F.H.,University of Witwatersrand |
Neumann F.H.,University of the Free State |
Neumann F.H.,Steinmann Institute For Geologie |
Scott L.,University of the Free State |
And 3 more authors.
Review of Palaeobotany and Palynology | Year: 2010
Palynological and sedimentological data from a core extracted from Lake Eteza shed new light on the Holocene vegetation and climate history in KwaZulu-Natal and can be linked to regional and global climate change. A 2072. cm core with nineteen radiocarbon dates and chronological extrapolation to the bottom of the sequence suggests that sedimentation started ca. 10. 200. cal. yrs. BP. Between ca. 10. 200 and 6800. cal. yrs. BP pollen indicators point to a change from intermediately humid conditions to comparatively drier grassy environments. This is in good agreement with Sea Surface Temperature (SST) fluctuations from a core in the Mozambique Channel which influence precipitation in coastal KwaZulu-Natal, and the beginning of the Holocene Thermal Maximum ca. 10. 500. cal. yrs. BP. The lower section of the core corresponds to gradually increasing Holocene sea levels along the coast and development of freshwater or estuarine conditions at Lake Eteza. The middle Holocene (ca. 6800-3600. cal. yrs. BP), when the sea level reached its highest stand and SST peak, indicate humid climatic conditions that favoured an increase of forest trees, e.g. Podocarpus, and undergrowth plants like Issoglossa. As a consequence of higher precipitation and increase of the water table, conditions were favourable for the spread of mangrove, swamp and possibly riverine forest. During the late Holocene after ca. 3600. cal. yrs. BP a decrease of Podocarpus and other trees as well as an increase of Chenopodiaceae/Amaranthaceae, grasses and Phoenix coincide with a return to lower sea levels and drier conditions. The decrease of all trees including Phoenix at ca. 700. cal. yrs. BP, accompanied by rapid sedimentation rates, possibly reflect forest clearing and upland erosion induced by activities of Iron Age settlers. A dry period at the globally recognized onset of the Little Ice Age might have contributed to these changes. Late Iron Age settlers have probably already introduced Zea mays, which was detected in the profile since ca. 210. BP. The appearance of neophytes like Pinus, Casuarina and pollen of Ambrosia-type in the youngest sediments indicates increased disturbance of European settlements and land use since ca. 100. cal. yrs. BP. © 2010 Elsevier B.V.
McCann T.,Steinmann Institute For Geologie
Zeitschrift der Deutschen Gesellschaft fur Geowissenschaften | Year: 2010
The age and location of the Palaeogene lignite deposits found in three large opencast lignite mines (Vastan, Tadkeshwar and Rajpardi) in the region of Surat, Gujarat, western India, are of particular interest because of the coincidence of deposition and the collision of the Indian subcontinent with Eurasia. Detailed analysis of the outcrops has allowed the recognition of a variety of sedimentary facies, including lignites (and associated amber layers), mudstones, sandstones, carbonates and shell-rich horizons. The succession can be grouped into three predominant facies, namely, a) the shell beds, which are intimately associated with marked thicknesses of b) low-energy muds and c) lignites. The depositional system is interpreted as a nearshore/coastal chenier plain, similar to the extensive coastal systems developed along the northeast coast of present-day South America. Conditions along this mud-dominated coast were controlled by moist atmospheric conditions, which support the idea that India had entered the equatorial humid belt at the same time as the collision of India-Eurasia occurred. © 2010 E. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, Germany.
Schwermann A.H.,Steinmann Institute For Geologie |
Martin T.,Steinmann Institute For Geologie
Palaontologische Zeitschrift | Year: 2012
The partial skeleton of a young adult Geotrypus antiquus (de Blainville 1840) from the Upper Oligocene (MP 28) found in Enspel comprises the skull with both mandibles, distal ends of both scapulae, left clavicula, humeri, ulnae and radii of both sides, various elements of the hand, some vertebrae, ribs, and the left femur. For the first time, the previously postulated association between dentition and postcranial elements can be confirmed. The skeleton exhibits strong adaptations for a subterranean life, similar to modern fossorial moles. The humerus is wide with a large pectoral process. The wing-like greater and lesser tuberosities, teres tubercle, and distal epicondylus are clearly developed. The metacarpals and phalanges are broad and stout. There are several sesamoid bones in the broad digging hand, including a prepollex (os falciforme). The preserved bones allowed the forelimb of G. antiquus to be reconstructed. Previous finds of G. antiquus have mainly been from France, with a few specimens from Switzerland and southern Germany. The specimen from Enspel is the northernmost record. A cladistic analysis, based on the matrix of Sánchez-Villagra et al. (Cladistics 22:59-88, 2006), confirms the basal position of Geotrypus within the Old World moles (Talpini). © 2012 Springer-Verlag.
Osteology and phylogeny of Westphaliasaurus simonsensii: A new plesiosaurid (Sauropterygia) from the Lower Jurassic (Pliensbachian) of Sommersell (Höxter District), North Rhine-Westphalia, Germany [Osteologie und Phylogenie von Westphaliasaurus simonsensii: Ein neuer Plesiosauride (Sauropterygia) aus dem Unteren Jura (Pliensbachium) von Sommersell (Kreis Höxter), Nordrhein-Westfalen, Deutschland]
Schwermann L.,Steinmann Institute For Geologie |
Sander P.M.,Steinmann Institute For Geologie
Geologie und Palaeontologie in Westfalen | Year: 2011
In June 2007 the partly articulated skeleton of a plesiosaur from the Lower Jurassic (Pliensbachian) was found in a clay pit named .,in Sommersell, district Höxter, North Rhine-Westphalia, Germany. It was recovered and afterwards prepared by the Museum of Natural History in Münster (Westfalia). The stratigraphical position of the specimen is between common taxa from the Hettangian and Sinemurian of Enland and the Toarcian of Southern Germany and England. The skull as well as the distal parts of the limbs is not preserved, but the bigger part of the axial skeleton is retained. A total of 76 vertebrae, pectoral and pelvic girdles and the proximal parts of the fore- and hindlimbs (humerus, radius, ulna/femur, tibia, fibula) are existant. Carpals, tarsals and phalanges are scattered around the specimen.addition to the osteological description of the specimen a comparison with common Lower Jurassic taxa in the literature and with material from the collections of the Natural History Museum in London and the "Staatliches Museum für Naturkunde" in Stuttgart was made. Some characters distinguish the Sommersell taxon distinctly from existant taxa. After the osteological comparison the discreteness of the specimen was verified by a phylogenetical analysis. For this purpose the specimen was subjoined to the dataset of KETCHUM & BENSON (2010). The result approved the assumption that was generated during the osteological description and comparison and shows distinctly that the specimen from Sommersell is a new taxon. It is based on the combination of a total of six unambiguous synapomorphies. Three of these synapomorphies are unique in between the Plesiosauridae. Together with Plesiosaurus dolichodeirus, Seeleyosaurus guelmiimperatoris, Microcleidus homalospondylus, Occitanosaurus tournemirensis and Hydrorion brachypterygius the Sommersell taxon is situated in the monophyletic taxon Plesiosauridae. The stratigraphical as well as the paleogeographical position also support these results. On the base of the results of the phylogenetic analysis a new genus and a new species, Westphaliasaurus simonsensii, are erected for the taxon from Sommersell. © 2011 Landschaftsverband Westfalen-Lippe.