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Coiffard C.,Leibniz Institute for Research on Evolution and Biodiversity | Mohr B.A.R.,Leibniz Institute for Research on Evolution and Biodiversity | Bernardes-de-Oliveira M.E.C.,Guarulhos University | Bernardes-de-Oliveira M.E.C.,University of Sao Paulo
Taxon | Year: 2013

Morphology and anatomy of a fossil nymphaealean plant, Jaguariba wiersemana gen. nov. et sp. nov. from the late Early Cretaceous of northeastern Brazil, and extant aquatic flowering plants are comparatively studied. Characteristic features indicate that Jaguariba gen. nov. is a member of Nymphaeaceae, and may belong to Nymphaeoideae. The occurrence of both Nymphaeaceae and Cabombaceae (e.g., Pluricarpellatia peltata) in the Lower Cretaceous contradicts recent molecular dating implying a Late Cretaceous-Early Tertiary divergence for those families. Furthermore, the morphology of the fossil and sedimentologic and taphonomic data indicate that Jaguariba gen. nov. had an aquatic ecology similar to living Nymphaeaceae. Thus the taxon was part of the aquatic vegetation of the Crato lake in association with Pluricarpellatia peltata, an earlier described cabombaceaen aquatic angiosperm.


Kammerer C.F.,Leibniz Institute for Research on Evolution and Biodiversity | Frobisch J.,Leibniz Institute for Research on Evolution and Biodiversity | Angielczyk K.D.,Field Museum of Natural History
PLoS ONE | Year: 2013

The large dicynodont Eubrachiosaurus browni from the Upper Triassic Popo Agie Formation of Wyoming is redescribed. Eubrachiosaurus is a valid taxon that differs from Placerias hesternus, with which it was previously synonymized, by greater anteroposterior expansion of the scapula dorsally and a very large, nearly rectangular humeral ectepicondyle with a broad supinator process. Inclusion of Eubrachiosaurus in a revised phylogenetic analysis of anomodont therapsids indicates that it is a stahleckeriid closely related to the South American genera Ischigualastia and Jachaleria. The recognition of Eubrachiosaurus as a distinct lineage of North American dicynodonts, combined with other recent discoveries in the eastern USA and Europe, alters our perception of Late Triassic dicynodont diversity in the northern hemisphere. Rather than being isolated relicts in previously therapsid-dominated regions, Late Triassic stahleckeriid dicynodonts were continuing to disperse and diversify, even in areas like western North America that were otherwise uninhabited by coeval therapsids (i.e., cynodonts). © 2013 Kammerer et al.


Ruta M.,University of Lincoln | Angielczyk K.D.,Field Museum of Natural History | Frobisch J.,Leibniz Institute for Research on Evolution and Biodiversity | Benton M.J.,University of Bristol
Proceedings of the Royal Society B: Biological Sciences | Year: 2013

Adaptive radiations are central to macroevolutionary theory. Whether triggered by acquisition of new traits or ecological opportunities arising from mass extinctions, it is debated whether adaptive radiations are marked by initial expansion of taxic diversity or of morphological disparity (the range of anatomical form). If a group rediversifies following a mass extinction, it is said to have passed through a macroevolutionary bottleneck, and the loss of taxic or phylogenetic diversity may limit the amount of morphological novelty that it can subsequently generate. Anomodont therapsids, a diverse clade of Permian and Triassic herbivorous tetrapods, passed through a bottleneck during the end-Permian mass extinction. Their taxic diversity increased during the Permian, declined significantly at the Permo-Triassic boundary and rebounded during the Middle Triassic before the clade's final extinction at the end of the Triassic. By sharp contrast, disparity declined steadily during most of anomodont history. Our results highlight three main aspects of adaptive radiations: (i) diversity and disparity are generally decoupled; (ii) models of radiations following mass extinctions may differ from those triggered by other causes (e.g. trait acquisition); and (iii) the bottleneck caused by a mass extinction means that a clade can emerge lacking its original potential for generating morphological variety. © 2013 The Author(s) Published by the Royal Society. All rights reserved.


Zancolli G.,University of Würzburg | Steffan-Dewenter I.,University of Würzburg | Rodel M.-O.,Leibniz Institute for Research on Evolution and Biodiversity
Diversity and Distributions | Year: 2014

Aim: Elevational gradients and land use changes can act together as drivers of species richness and composition. Responses to these drivers can be multidirectional, and resulting patterns of diversity might be unexpected or difficult to interpret. Present ecological relationships often reflect a legacy resulting from the influence of past geological, climatic and environmental changes on species dispersal, extinction and speciation. Here, we investigate amphibian diversity along altitudinal and disturbance gradients and evaluate how historical events may underlie contemporary distributional patterns. Location: Mount Kilimanjaro, Tanzania. Methods: During two rainy seasons in 2011, we recorded anurans at 36 sites from the foothills to 3500 m altitude. A combination of multiple regression, ordination technique and cluster analysis were used to determine the effects of altitudinal changes and habitat modification on species richness and composition. Furthermore, we compared the anuran fauna of Mt. Kilimanjaro with other East African mountains by means of cluster analysis and analysed patterns of distributions with a special focus on montane forest species. Results: Species richness declined with elevation and species assemblages were distinctly separated between lowland and highland altitudes. Presence of water bodies locally increased species richness, but we did not find significant correlations of species richness with other environmental variables. Mountains clustered into two major groups which reflected latitudinal position and differences in species distributions. Main conclusions: This study highlights the importance of considering the geological history of a place especially when assessing the effects of anthropogenic disturbance. The young age of the volcano and the complex biogeographical processes which occurred in East Africa during the last 20 million years prevented most montane forest frogs from colonizing Mt. Kilimanjaro. Increasing aridification and land use changes may cause contraction of breeding sites with consequent local extinctions in the near future. © 2013 John Wiley & Sons Ltd.


Adum G.B.,Range Resources | Eichhorn M.P.,University of Nottingham | Oduro W.,Range Resources | Ofori-Boateng C.,Range Resources | And 2 more authors.
Conservation Biology | Year: 2013

There is a lack of quantitative information on the effectiveness of selective-logging practices in ameliorating effects of logging on faunal communities. We conducted a large-scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest-dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance-tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance-tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low-intensity logging (≤3 trees/ha) a minimum 20-year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. © 2012 Society for Conservation Biology.


Korn D.,Leibniz Institute for Research on Evolution and Biodiversity
Evolution and Development | Year: 2012

Ammonoids are well-known objects used for studies on ontogeny and phylogeny, but a quantification of ontogenetic change has not yet been carried out. Their planispirally coiled conchs allow for a study of "longitudinal" ontogenetic data, that is data of ontogenetic trajectories that can be obtained from a single specimen. Therefore, they provide a good model for ontogenetic studies of geometry in other shelled organisms. Using modifications of three cardinal conch dimensions, computer simulations can model artificial conchs. The trajectories of ontogenetic allometry of these simulations can be analyzed in great detail in a theoretical morphospace. A method for the classification of conch ontogeny and quantification of the degree of allometry is proposed. Using high-precision cross-sections, the allometric conch growth of real ammonoids can be documented and compared. The members of the Ammonoidea show a wide variety of allometric growth, ranging from near isometry to monophasic, biphasic, or polyphasic allometry. Selected examples of Palaeozoic and Mesozoic ammonoids are shown with respect to their degree of change during ontogeny of the conch. © 2012 Wiley Periodicals, Inc.


Walther M.,Leibniz Institute for Research on Evolution and Biodiversity | Frobisch J.,Leibniz Institute for Research on Evolution and Biodiversity
Comptes Rendus - Palevol | Year: 2013

The quality of the fossil record of anomodont synapsids, one of the major clades of Permian-Triassic terrestrial tetrapods, is assessed. A Character Completeness Metric (CCM2) is calculated for each taxon and consecutive time intervals at a global scale and in the South African Karoo Basin. The mean completeness score is 66.80% (globally) and 77.37% (regionally) with completeness ranging between 60.12% and 91.33% per time interval. Up-to-date taxic, phylogenetic and residual diversity estimates confirm the general biodiversity trends recovered by recent analyses. The consistently high CCM2 scores throughout their evolutionary history together with a lack of correlation with biodiversity patterns and sampling proxies document a high quality of the known anomodont fossil record. In fact, when compared to other vertebrate groups, the completeness values for anomodonts are exceptionally high. Yet, whether this pattern results from the unrivalled record of the Karoo Basin or whether it is clade-specific and unique to anomodonts remains to be tested. © 2013 Académie des sciences.


Hoch H.,Leibniz Institute for Research on Evolution and Biodiversity | Ferreira R.L.,Federal University of Lavras
Mitteilungen aus dem Museum fur Naturkunde in Berlin - Deutsche Entomologische Zeitschrift | Year: 2012

A new troglobitic (obligate cavernicolous) species of the cixiid tribe Cixiini is described from Brazil. It could not be placed in any of the described genera, thus a new genus is established. Information on its distribution and ecology are given. This is the first record of a troglobitic planthopper from Brazil, and only the fifth troglobitic cixiid species from the Neotropics. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.


Shi C.,Capital Normal University | Ohl M.,Leibniz Institute for Research on Evolution and Biodiversity | Wunderlich J.,Oberer Hauselbergweg 24 | Ren D.,Capital Normal University
Cretaceous Research | Year: 2015

Micromantispa cristata gen. et sp. nov. is described from the Cretaceous amber of Myanmar. This is the smallest mantispid. Its raptorial forelegs are relatively slender, bearing dense spines and setae on femora and tibia. The first tarsal segment has two long spines on the dorsal apical, which is newly observed in the family. The morphological diversity of the prothorax and raptorial forelegs in Mantispidae through the geological history are discussed. © 2014 Elsevier Ltd.


Nagy M.,Leibniz Institute for Research on Evolution and Biodiversity | Gunther L.,Leibniz Institute for Research on Evolution and Biodiversity | Knornschild M.,University of Ulm | Mayer F.,Leibniz Institute for Research on Evolution and Biodiversity
Molecular Ecology | Year: 2013

The ultimate causes for predominant male-biased dispersal (MBD) in mammals and female-biased dispersal (FBD) in birds are still subject to much debate. Studying exceptions to general patterns of dispersal, for example, FBD in mammals, provides a valuable opportunity to test the validity of proposed evolutionary pressures. We used long-term behavioural and genetic data on individually banded Proboscis bats (Rhynchonycteris naso) to show that this species is one of the rare mammalian exceptions with FBD. Our results suggest that all females disperse from their natal colonies prior to first reproduction and that a substantial proportion of males are philopatric and reproduce in their natal colonies, although male immigration has also been detected. The age of females at first conception falls below the tenure of males, suggesting that females disperse to avoid father-daughter inbreeding. Male philopatry in this species is intriguing because Proboscis bats do not share the usual mammalian correlates (i.e. resource-defence polygyny and/or kin cooperation) of male philopatry. They have a mating strategy based on female defence, where local mate competition between male kin is supposedly severe and should prevent the evolution of male philopatry. However, in contrast to immigrant males, philopatric males may profit from acquaintance with the natal foraging grounds and may be able to attain dominance easier and/or earlier in life. Our results on Proboscis bats lent additional support to the importance of inbreeding avoidance in shaping sex-biased dispersal patterns and suggest that resource defence by males or kin cooperation cannot fully explain the evolution of male philopatry in mammals. © 2013 Blackwell Publishing Ltd.

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