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Schweizer M.,Naturhistorisches Museum der Burgergemeinde Bern | Seehausen O.,University of Bern | Seehausen O.,Eawag - Swiss Federal Institute of Aquatic Science and Technology | Hertwig S.T.,Naturhistorisches Museum der Burgergemeinde Bern
Journal of Biogeography | Year: 2011

Aim Parrots are thought to have originated on Gondwana during the Cretaceous. The initial split within crown group parrots separated the New Zealand taxa from the remaining extant species and was considered to coincide with the separation of New Zealand from Gondwana 82-85Ma, assuming that the diversification of parrots was mainly shaped by vicariance. However, the distribution patterns of several extant parrot groups cannot be explained without invoking transoceanic dispersal, challenging this assumption. Here, we present a temporal and spatial framework for the diversification of parrots using external avian fossils as calibration points in order to evaluate the relative importance of the influences of past climate change, plate tectonics and ecological opportunity. Location Australasian, African, Indo-Malayan and Neotropical regions. Methods Phylogenetic relationships were investigated using partial sequences of the nuclear genes c-mos, RAG-1 and Zenk of 75 parrot and 21 other avian taxa. Divergence dates and confidence intervals were estimated using a Bayesian relaxed molecular clock approach. Biogeographic patterns were evaluated taking temporal connectivity between areas into account. We tested whether diversification remained constant over time and if some parrot groups were more species-rich than expected given their age. Results Crown group diversification of parrots started only about 58Ma, in the Palaeogene, significantly later than previously thought. The Australasian lories and possibly also the Neotropical Arini were found to be unexpectedly species-rich. Diversification rates probably increased around the Eocene/Oligocene boundary and in the middle Miocene, during two periods of major global climatic aberrations characterized by global cooling. Main conclusions The diversification of parrots was shaped by climatic and geological events as well as by key innovations. Initial vicariance events caused by continental break-up were followed by transoceanic dispersal and local radiations. Habitat shifts caused by climate change and mountain orogenesis may have acted as a catalyst to the diversification by providing new ecological opportunities and challenges as well as by causing isolation as a result of habitat fragmentation. The lories constitute the only highly nectarivorous parrot clade, and their diet shift, associated with morphological innovation, may have acted as an evolutionary key innovation, allowing them to explore underutilized niches and promoting their diversification. © 2011 Blackwell Publishing Ltd.

News Article | December 7, 2015
Site: phys.org

A number of remarkable observations such as an enormous kidney, grooved three-pointed teeth and a huge seasonally present penis are reported in the recent study, conducted by Adrienne Jochum, Naturhistorisches Museum der Burgergemeinde Bern, Switzerland, and her international team of researchers from University of Bern, Switzerland; Shinshu University, Japan; Universitaetsklinikum Giessen und Marburg GmbH, Germany; Justus-Liebig University Giessen, Germany; University of Ljubljana, Slovenia; University of Bern Goethe-University Frankfurt, Germany; Ruhr University Bochum, Germany; Croatian Biospeleological Society, Croatia and University Duisburg-Essen, Germany. The scientists describe these characteristics as adaptations the miniature creatures have acquired in order to survive austerity in the subterranean realm. Usually, adaptations to cave life can include blindness or lack of eyes, loss of pigmentation, sensitivity to changes in temperature and humidity, a high starvation tolerance, or anatomical compromises such as small size and transparent shells. The present study shows that miniscule carychiid subterranean snails have developed huge organs to tolerate the unique conditions of cave life. "Studying adaptations in extreme environments such as those found in snails of subterranean habitats can help us to understand mechanisms driving evolution in these unique habitats," explains the first author. Glassy cave-dwelling snails known only from Northern Spain, the southern Eastern Alpine Arc and the Dinarides might have tiny hearts, but their enormous kidney extends from one to two thirds of the total length of their minute shells. This phenomenon could be explained as an effective mechanism used to flush out large amounts of excess water during flooding seasons in caves. The same impressive creatures have also developed elaborate muscular plates, forming the girdle that surrounds the gastric mill (gizzard) in their digestive tract. The muscular gizzard grinds the grainy stew of microorganisms and fungi the snails find in moist cave mud. These mysterious creatures graze stealthily using an elastic ribbon (radula), aligned with seemingly endless rows of three-pointed, centrally-grooved teeth, as they glide through the depths of karst caves while searching for food and partners. Deprived from the hospitable aspects of life we have grown used to, some of the snails discussed in the present paper have evolved their reproductive system in order to be able to reproduce in the harshest of environments, even when they fail to find a partner for an extended period of time. As a result, not only are these snails protandric hermaphrodites, meaning that they possess male sexual features initially, which later disappear so that the female phase is present, but they have a large retractable, pinecone-shaped penis for instantaneous mating in the summer when mating is most probable. To guarantee offspring, a round sac, known as the receptaculum seminis, stocks sperm received from a partner during a previous mating and allows them to self-inseminate if necessary. Teeth in these cave snails are also described using histology for the first time. They bear a median groove on the characteristic cusps known for the Carychiidae. Sketchy, past dissections provide the current knowledge upon which the findings from this investigation are based. Otherwise, historical descriptions of these tiny snails are only known from empty shells found in samples of cave sediment. The genus Zospeum can only be found alive by inspecting cave walls using a magnifying glass. "Knowledge of their subterranean ecology as well as a "gut feeling" of where they might be gliding about in their glassy shells is necessary to find them," comments Adrienne Jochum. The authors also emphasize that this groundbreaking work is important for biodiversity studies, for biogeographical investigations and for conservation management strategies. Adrienne Jochum and her team investigated the insides of the shells using nanoCT to differentiate species in synchronization with molecular approaches for genetic delimitation. Four well-defined genetic lineages were determined from a total of sixteen Zospeum specimens found in the type locality region of the most common representative, Zospeum isselianum. This investigation is the first integrative study of live-collected Zospeum cave snails using multiple lines of data (molecular analyses, scanning electron microscopy (SEM), nano-computer tomography (nanoCT), and histology. This work is dedicated to the industrious Slovenian malacologist Joze Bole, whose work greatly inspired the present research. Explore further: Life deep down: A new beautiful translucent snail from the deepest cave in Croatia More information: Jochum A, Slapnik R, Klussmann-Kolb A, Páll-Gergely B, Kampschulte M, Martels G, Vrabec M, Nesselhauf C, Weigand AM (2015) Groping through the black box of variability: An integrative taxonomic and nomenclatural re-evaluation of Zospeum isselianum Pollonera, 1887 and allied species using new imaging technology (Nano-CT, SEM), conchological, histological and molecular data (Ellobioidea, Carychiidae). Subterranean Biology 16: 123-165. DOI: 10.3897/subtbiol.16.5758

Korrida A.,University Ibn Zohr | Schweizer M.,Naturhistorisches Museum der Burgergemeinde Bern
Journal of Zoological Systematics and Evolutionary Research | Year: 2014

Studies on the influence of Pleistocene climatic fluctuations and associated habitat changes on arid-adapted bird species living in the Holarctic region are comparatively rare. In contrast to temperate species, the populations of arid-adapted avian species might be characterized by low genetic differentiation because periods of population isolation were associated with the short interglacial periods, while population expansion events might have occurred during the longer glacial periods when steppe-like vegetation might have been prevalent. In this study, we tested this hypothesis in a widespread arid-adapted taxon of the Palaearctic desert belt, the Houbara-Macqueen's bustard complex. The later includes the Houbara bustard Chlamydotis undulata, comprising the North African subspecies Chlamydotis u. undulata and Chlamydotis u. fuertaventurae from the Canary Islands, and the Asian Macqueen's bustard Chlamydotis macqueenii. A long fragment (1042 bp) of the Cyt-b gene was investigated in 39 representatives of the two species to assess phylogenetic and phylogeographic patterns, and demographic history and to compute divergence time estimates using a Bayesian relaxed molecular clock approach based on different coalescent priors. While the two species are genetically distinct, we found little intraspecific genetic differentiation. The divergence time of the two species falls within a period of extreme aridity at around 0.9 million years ago, which most likely resulted in an east-west vicariance along the Arabo-Saharan deserts. Differentiation within Houbara and Macqueen's bustard occurred later during the Middle to Upper Pleistocene, and as we have predicted, periods of range expansion were associated to the last glacial period at least in the Macqueen's bustard. © 2013 Blackwell Verlag GmbH.

Hertwig S.T.,Naturhistorisches Museum der Burgergemeinde Bern | Schweizer M.,Naturhistorisches Museum der Burgergemeinde Bern | Das I.,University Malaysia Sarawak | Haas A.,Biozentrum Grindel und Zoologisches Museum Hamburg
Molecular Phylogenetics and Evolution | Year: 2013

The tree-frog family Rhacophoridae is a major group contributing to the high pecies richness and reproductive diversity among vertebrates of Sundaland. Nonetheless, rhacophorid evolution, specially on Borneo, has not been studied within a phylogenetic context. In this study, we examine the phylogenetic relationships of 38 (out of 41) Bornean species of Rhacophoridae, in combination with data from previous phylogenetic studies. In the final super matrix of 91 species, we analyse sequence data from two mitochondrial and three nuclear genes. The resulting trees show the genus Rhacophorus as a paraphyletic assemblage. As a consequence, we transfer Rhacophorus appendiculatus and R. kajau to two other genera and propose the new phylogeny-based combinations- Kurixalus appendiculatus and Feihyla kajau, respectively. Furthermore, we use our phylogenetic hypotheses to reconstruct the evolution of reproductive modes in rhacophorid tree frogs. Direct development to the exclusion of a free larval stage evolved twice independently, once in an ancestor of the Pseudophilautus+. Raorchestes clade in India and Sri Lanka, and once within Philautus in Southeast Asia. The deposition of egg clutches covered by a layer of jelly in Feihyla is also present in F. kajau and thus confirms our generic reassignment. The remarkably high diversity of rhacophorid tree frogs on Borneo is the outcome of a complex pattern of repeated vicariance and dispersal events caused by past changes in the climatic and geological history of the Sunda shelf. We identified geographic clades of closely related endemic species within Rhacophorus and Philautus, which result from local island radiations on Borneo. © 2013 Elsevier Inc.

Britz R.,Natural History Museum in London | Conway K.W.,Texas A&M University | Ruber L.,Naturhistorisches Museum der Burgergemeinde Bern
Zoological Journal of the Linnean Society | Year: 2014

We review the morphological and molecular evidence that Mayden & Chen recently used to infer that the developmentally truncated fish genus Paedocypris is not a member of the teleost order Cypriniformes or carp-like fishes, but is 'the basal sister group to all Cypriniformes'. This hypothesis contradicts several previous studies that used molecular sequence data or morphological characters. A review of the morphological characters that Mayden & Chen discussed and mapped onto their 'simplified tree' shows that these, analysed alone, rather support a close relationship of the cyprinids Sundadanio, Danionella, and Paedocypris. We also present four additional analyses of morphological data, which all contradict Mayden & Chen's result. Despite its highly reductive skeleton, posing a serious problem when analysing its phylogenetic position with skeletal characters, the presence in Paedocypris of the basioccipital masticatory plate is compelling evidence that it is a member of the Cyprinoidei (Cyprinidae plus Psilorhynchidae). Our reanalysis and exploration of their molecular sequence data shows that only a single gene, EGR3, of the six nuclear genes analysed by Mayden & Chen, is responsible for the position of Paedocypris as 'the basal sister group to all Cypriniformes'. Three independent methods to visualize and analyse phylogenetic signal and conflict of data sets (phylogenetic networks, splits analysis methods or SAMS, and site-wise likelihood analyses) reveal a high level of character conflict and noise in Mayden & Chen's data set. The 'basal' position of Paedocypris seems to be the outcome of the interplay of two long-branch effects. We apply the same analytical methods to the data set from Rüber etal.'s molecular analysis of the phylogenetic position of Paedocypris and discuss our findings. We conclude that none of the molecular data sets compiled to date can establish the phylogenetic position of Paedocypris with confidence. Morphological data suggest that Paedocypris and Danionella are sister genera, and that their closest relative is Sundadanio, although the position of these three miniatures among cyprinoids is still unclear. © 2014 The Linnean Society of London.

Germann C.,Naturhistorisches Museum der Burgergemeinde Bern
Revue Suisse de Zoologie | Year: 2015

Styphlidius brevisetis Osella, 1981 and S. globosus Osella, 1981 are raised to species level. Both were hitherto ranked as subspecies of S. corcyreus (Reitter, 1884). Styphlidius pelops sp. nov. is described from the Peloponnese. All specimens of the new species were sifted from leaf litter, moss and plant debris. Styphlidius corcyreus is recorded for the first time from Albania. A revised key to all five species is presented and an overview of the species' distribution is given.

Schweizer M.,Naturhistorisches Museum der Burgergemeinde Bern | Shirihai H.,c o Ausserdorfstrasse 6
Molecular Phylogenetics and Evolution | Year: 2013

The morphologically inferred Oenanthe lugens complex comprises nine taxa of open-habitat chats which occur in rocky and/or mountainous areas adjacent to the Saharo-Sindian desert belt. It has traditionally been divided into the lugubris group of north-east Africa, the lugentoides group of the southern part of the Arabian Peninsula and the lugens group of North Africa and the Middle East. Previous molecular phylogenetic studies have shown that the O lugens complex might not be monophyletic. However, it remained unclear how this result might have been affected by incomplete taxon sampling, as the lugentoides group and two out of three taxa of the lugubris group have not been analyzed so far. In this study, we present a phylogenetic hypothesis of the O lugens complex based on two mitochondrial genes and one nuclear intron using, for the first time, a complete taxon sampling. The application of a multispecies coalescent approach allowed us to simultaneously estimate the sequence and timing of speciation events. The O lugens complex was consistently revealed as a polyphyletic assemblage and the traditionally recognized groups should be treated as at least three different species: O. lugens, Oenanthe lugubris, and Oenanthe lugentoides. While O. lugubris and O. lugentoides were revealed to be sister groups, O. lugens was found to be closely related to the species pair Oenanthe chrysopygia/. Oenanthe xanthoprymna. The latter differ quite strongly in morphology and have traditionally not been associated with members of the lugens complex. We thus corroborate the results of previous studies, which demonstrated that morphology seems to be a poor predictor of phylogenetic relationships in Oenanthe. In contrast to the mtDNA markers analyzed, it was revealed that differences among taxa were not fixed in the nuclear intron. In the case of the taxa persica of the lugens group, an influence of introgression in autosomal markers cannot be excluded and deserves further study. The three species O. lugens, O. lugubris, and O. lugentoides and their associated taxa comprise a comparatively young radiation, which started to diversify in the Pliocene with major diversification events during the Pleistocene. The different taxa seem to have evolved during periods of increased aridity in isolation in rocky mountainous areas adjacent to hyper arid regions. © 2013 Elsevier Inc.

Schweizer M.,Naturhistorisches Museum der Burgergemeinde Bern | Guntert M.,Naturhistorisches Museum der Burgergemeinde Bern | Hertwig S.T.,Naturhistorisches Museum der Burgergemeinde Bern
Zoologica Scripta | Year: 2013

Aridification from mid-Miocene onwards led to a fragmentation of mesic biomes in Australia and an expansion of arid habitats. This influenced the diversification of terrestrial organisms, and the general direction of their radiations is supposed to have been from mesic into drier habitats. We tested this hypothesis in the platycercine parrots that occur in different habitats in Australia and also colonized Pacific islands. We inferred their temporal and spatial diversification patterns using a Bayesian relaxed molecular clock approach based on three nuclear and two mitochondrial genes and model-based biogeographic reconstructions. The Bassian biota was found to be the centre of origin of platycercine parrots and diversification within two of their three clades coincided with the beginning of aridification of Australia. The associated habitat changes may have catalysed their radiation through adaptation to arid environments and vicariance because of the fragmentation of non-arid habitats. The small oceanic islands of Melanesia contributed as stepping stones for the colonization of New Zealand from Australia. © 2012 The Authors Zoologica Scripta © 2012 The Norwegian Academy of Science and Letters.

De Pietri V.L.,Naturhistorisches Museum der Burgergemeinde Bern | Mayr G.,Senckenberg Institute
Palaeontology | Year: 2012

'Totanus'lartetianus, Elorius paludicola and 'Tringa'gracilis are the three scolopacid birds from the early Miocene of Saint-Gérand-le-Puy described by the French palaeontologist Milne-Edwards in the 19th century. Since then, no revision of these taxa has been performed. Our re-examination revealed that not much of the material originally assigned to 'Totanus'lartetianus can be retained within the species. Presumably plesiomorphic features of the humerus - and potentially the coracoid we attributed to this taxon - indicate that it is misplaced in the extant scolopacid genus and may not even belong to the Scolopacidae (sandpipers and allies), and we therefore place it in the new genus Scolopacimilis. Comparisons of the material assigned to Elorius paludicola and 'Tringa'gracilis show that they are morphologically similar, both exhibiting distinct scolopacid anatomical features. The latter, however, cannot be referred to the extant taxon Tringa and is classified into the new genus Parvelorius. We further introduce three new species, ?Elorius limosoides sp. nov., and ?Parvelorius calidris sp. nov., which we have tentatively assigned to the extinct scolopacid genera Elorius and Parvelorius, respectively, and Becassius charadriioides gen. et. sp. nov., which, together with Scolopacimilis, display a morphology uncharacteristic for extant Scolopaci. For the first time we have assigned skulls to some of the postcranial elements described in this study. The presence of at least six species of Scolopaci from the early Miocene considerably increases the number of members of the group known from this time. © The Palaeontological Association.

13 subspecies are usually accepted in the Yellow Wagtail which chiefly differ in their head pattern. Most subspecies have parapatric breeding areas and hybridise in contact zones. Two subspecies breed locally in Switzerland: the nominate subspecies dominates north of the Alps, while cinereocapilla breeds mainly in the Rhone valley (cantons of Valais and Vaud) as well as in the canton of Ticino. These two subspecies, however, admix at least in the region of the Seeland (cantons of Berne and Fribourg) and in the canton of Geneva. Additionally, thunbergi is a regular passage migrant in the whole country. In contrast, the subspecies feldegg and flavissima/lutea occur only irregularly and their records have to be submitted to the Swiss Rarities Committee (SRC). Intermediate birds between feldegg and other subspecies have been recorded several times. They have been treated under feldegg as long as they could be distinguished from locally breeding intermediate forms. According to current knowledge, flavissima and lutea cannot be separated with certitude. Hence, the SRC treats them together although the northwest European subspecies flavissima is more likely to occur than the chiefly central Asian subspecies lutea. Several observations of the southwest European and northwest African subspecies iberiae have been reported during the last years. Iberiae can probably not be safely distinguished from certain locally breeding intermediate birds between flava and cinereocapilla. As a consequence, the SRC does no longer treat records of the subspecies iberiae. Nevertheless, well documented observations of birds with phenotypic features of this subspecies are still archived.

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