Zoologisches Forschungsmuseum Alexander Koenig
Zoologisches Forschungsmuseum Alexander Koenig
Petschenka G.,Justus Liebig University |
Wagscha V.,University of Hamburg |
Von Tschirnhaus M.,Bielefeld University |
Donath A.,Zoologisches Forschungsmuseum Alexander Koenig |
Dobler S.,University of Hamburg
American Naturalist | Year: 2017
Natural selection imposed by natural toxins has led to striking levels of convergent evolution at the molecular level. Cardiac glycosides represent a group of plant toxins that block the Na,KATPase, a vital membrane protein in animals. Several herbivorous insects have convergently evolved resistant Na,K-ATPases, and in some species, convergent gene duplications have also arisen, likely to cope with pleiotropic costs of resistance. To understand the genetic basis and predictability of these adaptations, we studied five independent lineages of leaf-mining flies (Diptera: Agromyzidae). These flies have colonized host plants in four botanical families that convergently evolved cardiac glycosides of two structural types: cardenolides and bufadienolides. We compared each of six fly species feeding on such plants to a phylogenetically related but nonadapted species. Irrespective of the type of cardiac glycoside in the host plant, five out of six exposed species displayed substitutions in the cardiac glycoside– binding site of the Na,K-ATPase that were previously described in other insect orders; in only one species was the gene duplicated. In vitro assays of nervous tissue extractions confirmed that the substitutions lead to increased resistance of the Na,K-ATPase. Our results demonstrate that target site insensitivity of Na,K-ATPase is a common response to dietary cardiac glycosides leading to highly predictable amino acid changes; nonetheless, convergent evolution of gene duplication for this multifunctional enzyme appears more constrained. © 2017 by The University of Chicago.
Agency: European Commission | Branch: H2020 | Program: MSCA-ITN-ETN | Phase: MSCA-ITN-2014-ETN | Award Amount: 3.89M | Year: 2015
BIG4 is a global network to amalgamate the cutting edge methods of genomics, phylogenetics, informatics, taxonomy, semantic biodiversity publishing and citizen science, into highly competitive cross-disciplinary training programme for 15 ESRs with a stronghold in biosystematics. These 15 future leaders will extend the exploration of the four biggest groups of living organisms in a more forward looking way than has been attempted before. The urgent focus on the big four insect groups, i.e. Coleoptera (beetles), Hymenoptera (wasps, ants and bees), Diptera (flies and mosquitoes), and Lepidoptera (butterflies and moths) is justified by the super abundance of this form of Life, and by the growing need by science and society to make better use of the enormous potential hidden in their biological diversity. BIG4 aims  to gain a robust systematic knowledge that explains the evolutionary origin, diversification, past and present distributions of living organisms,  to model their future dispersal and  to predict the traits of species that are yet unknown. Additionally, BIG4 strives for  implementing organismal features into engineering, medicine, agricultural or environmental solutions, the insect flight mechanics and more effective pollination to mention just a few. Such knowledge is in a particularly high demand in respect of the four biggest insects groups comprising the most important model organisms, the most dangerous pests or disease vectors, the most abundant invasive species and the most fragile entire species communities undergoing extinction due to habitat destruction. By integrating academia with the business and public sectors, BIG4 will greatly increase services and beneficial products provided by the biosystematics as a science. BIG4 will place insect mega-diversity as a powerful service for economic and societal needs such as environmental monitoring, biological control, biomedicine, or ecological farming.
Letsch H.O.,Zoologisches Forschungsmuseum Alexander Koenig |
Kjer K.M.,Rutgers University
BMC Evolutionary Biology | Year: 2011
Background: Failure to account for covariation patterns in helical regions of ribosomal RNA (rRNA) genes has the potential to misdirect the estimation of the phylogenetic signal of the data. Furthermore, the extremes of length variation among taxa, combined with regional substitution rate variation can mislead the alignment of rRNA sequences and thus distort subsequent tree reconstructions. However, recent developments in phylogenetic methodology now allow a comprehensive integration of secondary structures in alignment and tree reconstruction analyses based on rRNA sequences, which has been shown to correct some of these problems. Here, we explore the potentials of RNA substitution models and the interactions of specific model setups with the inherent pattern of covariation in rRNA stems and substitution rate variation among loop regions. Results: We found an explicit impact of RNA substitution models on tree reconstruction analyses. The application of specific RNA models in tree reconstructions is hampered by interaction between the appropriate modelling of covarying sites in stem regions, and excessive homoplasy in some loop regions. RNA models often failed to recover reasonable trees when single-stranded regions are excessively homoplastic, because these regions contribute a greater proportion of the data when covarying sites are essentially downweighted. In this context, the RNA6A model outperformed all other models, including the more parametrized RNA7 and RNA16 models. Conclusions: Our results depict a trade-off between increased accuracy in estimation of interdependencies in helical regions with the risk of magnifying positions lacking phylogenetic signal. We can therefore conclude that caution is warranted when applying rRNA covariation models, and suggest that loop regions be independently screened for phylogenetic signal, and eliminated when they are indistinguishable from random noise. In addition to covariation and homoplasy, other factors, like non-stationarity of substitution rates and base compositional heterogeneity, can disrupt the signal of ribosomal RNA data. All these factors dictate sophisticated estimation of evolutionary pattern in rRNA data, just as other molecular data require similarly complicated (but different) corrections. © 2011 Letsch and Kjer; licensee BioMed Central Ltd.
Schmidt A.K.D.,University of Graz |
Riede K.,Zoologisches Forschungsmuseum Alexander Koenig |
Romer H.,University of Graz
Journal of Experimental Biology | Year: 2011
Because of call frequency overlap and masking interference, the airborne sound channel represents a limited resource for communication in a species-rich cricket community like the tropical rainforest. Here we studied the frequency tuning of an auditory neuron mediating phonotaxis in the rainforest cricket Paroecanthus podagrosus, suffering from strong competition, in comparison with the same homologous neuron in two species of European field crickets, where such competition does not exist. As predicted, the rainforest species exhibited a more selective tuning compared with the European counterparts. The filter reduced background nocturnal noise levels by 26?dB, compared with only 16 and 10?dB in the two European species. We also quantified the performance of the sensory filter under the different filter regimes by examining the representation of the speciesspecific amplitude modulation of the male calling song, when embedded in background noise. Again, the filter of the rainforest cricket performed significantly better in terms of representing this important signal parameter. The neuronal representation of the calling song pattern within receivers was maintained for a wide range of signal-to-noise ratios because of the more sharply tuned sensory system and selective attention mechanisms. Finally, the rainforest cricket also showed an almost perfect match between the filter for sensitivity and the peripheral filter for directional hearing, in contrast to its European counterparts. We discuss the consequences of these adaptations for intraspecific acoustic communication and reproductive isolation between species. © 2011.
Peters G.,Zoologisches Forschungsmuseum Alexander Koenig
Mammal Review | Year: 2011
1 A negative correlation between body weight and frequency characteristics of a species' vocalizations exists in mammals, due to the acoustics of vocal sound production ('source-filter theory'; source = larynx; filter = supralaryngeal vocal tract) and the strong positive correlation between body weight and vocal tract length. 2 A negative correlation is hypothesized to exist between increasing body weight and frequency characteristics of calls during ontogeny as well. 3 This hypothesis is tested for mean dominant frequency (maximum spectral energy peak) of intense mew calls in juveniles of five species of the Felidae: lion Panthera leo, jaguar Panthera onca, leopard Panthera pardus, tiger Panthera tigris and puma Puma concolor. 4 In the five felid species in which the hyoid is incompletely ossified (genera Panthera and Uncia), the larynx undergoes a considerable ontogenetic descent, resulting in a proportionally longer vocal tract in adult individuals than in all other species of the family, which have a fully ossified hyoid without a descent. 5 In all five species studied here, mean dominant frequency decreases as body weight increases during growth. In the four Panthera species (with laryngeal descent) dominant frequency is determined by the vocal tract (the filter), and dominant frequency is largely similar at similar weights, indicating a similar correlation between the ontogenetic increase in body weight (and vocal tract length) and the decrease in mean dominant frequency. In the puma (without laryngeal descent) dominant frequency is determined by the larynx (the source), it is considerably higher than in the Panthera species, and the course of its ontogenetic decrease differs considerably from that in Panthera. 6 The data do not support a uniform scaling relationship between body weight and mean dominant frequency of intense mew calls in the Felidae during ontogenetic growth. © 2010 The Author. Journal compilation © 2010 Mammal Society.
Kuck P.,Zoologisches Forschungsmuseum Alexander Koenig |
Meusemann K.,Zoologisches Forschungsmuseum Alexander Koenig
Molecular Phylogenetics and Evolution | Year: 2010
FASconCAT is a user-friendly software that concatenates rapidly different kinds of sequence data into one supermatrix file. Output files are either in FASTA, PHYLIP or NEXUS format and are directly loadable in phylogenetic programs like PAUP*, RAxML or MrBayes. FASconCAT can handle FASTA, PHYLIP and CLUSTAL formatted input files in one single run. It provides useful information about each input file and the concatenated supermatrix. For example, the program provides the range information of each concatenated gene (partition) and delivers a check list of all concatenated sequences (taxa). Information about the base composition of single input files and the resulting supermatrix is supplied for nucleotide data. For given structure strings (e.g. secondary structures) it displays single unpaired (loop) and paired (stem) positions after the concatenation process. Optionally, FASconCAT generates NEXUS files of concatenated sequences, either with MrBayes commands directly executable in PAUP* and MrBayes, or without any specific commands. If favoured, FASconCAT dispenses output files in PHYLIP format with relaxed (unlimited signs) or restricted taxon names (up to ten signs) while sequences are printed in non-interleaved format. FASconCAT is implemented in Perl and freely available from http://software.zfmk.de. It runs on UNIX and MS Windows operating systems. © 2010 Elsevier Inc.
Rduch V.,Zoologisches Forschungsmuseum Alexander Koenig
Mammalian Biology | Year: 2016
Sympatric occurrence of puku (Kobus vardonii) and impala (Aepyceros melampus) characterises large parts of the protected areas in Zambia. The present study assessed traits of the populations as well as spatial and dietary overlap of both antelopes in Kafue National Park and adjacent Game Management Areas in western Zambia. Data were collected via distance sampling along line transects (population and distribution) and via microhistological analyses of dung (diet). Hunting activities might result in fewer males in both antelopes in the Game-Management areas. During the cool dry season there was considerable spatial overlap between puku and impala. However, puku are more abundant in grassland areas, while impala reach highest population densities in intermediate habitats. The diet of puku was characterised by high amounts of grasses during both the cool dry season and the late rainy season. Impala shifted from browsing during the cool dry season to a more grazing diet during the rainy season. This study found niche partitioning via habitat and diet as a key to understand the coexistence of these antelopes and improves our knowledge of Zambian Wildlife. © 2016 Deutsche Gesellschaft für Säugetierkunde.
Wagele H.,Zoologisches Forschungsmuseum Alexander Koenig |
Klussmann-Kolb A.,Goethe University Frankfurt |
Verbeek E.,Zoologisches Forschungsmuseum Alexander Koenig |
Schrodl M.,SNSB Zoologische Staatssammlung Munich
Organisms Diversity and Evolution | Year: 2014
Opisthobranchia have experienced an unsettled taxonomic history. At the moment their taxonomy is in state of dramatic flux as recent phylogenetic studies have revealed traditional Opisthobranchia to be paraphyletic or even polyphyletic, allocating some traditional opisthobranch taxa to other groups of Heterobranchia, e.g. Pulmonata. Here we review the history of Opisthobranchia and their subgroups, explain their traditionally proposed relationships, and outline the most recent phylogenetic analyses based on various methods (morphology, single gene and multiple gene analyses, as well as genomic data). We also present a phylogenetic hypothesis on Heterobranchia that, according to the latest results, represents a consensus and is the most probable one available to date. The proposed phylogeny supports the Acteonoidea outside of monophyletic Euthyneura, the basal euthyneuran split into Nudipleura (Nudibranchia plus Pleurobranchoidea) and the recently established taxon Tectipleura. The latter divides into the Euopisthobranchia, containing most of the major traditional opisthobranch clades, and the Panpulmonata, with a mix of the former opisthobranch, putative allogastropod and pulmonate taxa. This "new euthyneuran tree" rejects the traditional taxa Opisthobranchia and Pulmonata, and, in particular, has profound implications for preconceived textbook scenarios of opisthobranch and pulmonate evolution, which must now be reconsidered. In the absence of systematic barriers, research communities - which have traditionally investigated marine and non-marine heterobranchs separately - need to interact and finally merge for the sake of science. © 2013 The Author(s).
Schwarzer J.,Zoologisches Forschungsmuseum Alexander Koenig |
Misof B.,Zoologisches Forschungsmuseum Alexander Koenig |
Schliewen U.K.,Bavarian State Collection of Zoology
Journal of Evolutionary Biology | Year: 2012
Hybridization in animals is a much more common phenomenon as previously thought and may have profound implications for speciation research. The cichlid genus Steatocranus (Teleostei: Cichlidae), a close relative to members of the East African cichlid radiations, radiated under riverine conditions in the lower Congo rapids and produced a small species flock. Previous phylogenetic analyses suggested that hybridization occurred and contributed to speciation in this genus. A re-analysis of an already published 2000 loci-AFLP data set explicitly testing for patterns of ancient gene flow provided strong evidence for a highly reticulate phylogenetic history of the genus. We provide, to our knowledge, the first example of a complex reticulate network in vertebrates, including multiple closely related species connected through ancient as well as recent gene flow. In this context, the limited validity of strictly bifurcating tree hypotheses as a phylogenetic basis for hypothesis testing in evolutionary biology is discussed. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.
Wagner P.,Zoologisches Forschungsmuseum Alexander Koenig
Zootaxa | Year: 2010
In the course of a recent taxonomic study on East African Agama species it became clear that a population of A. caudospinosa Meek, 1910 from Mt. Kenya is clearly distinct to specimens from the type locality at Lake Elmenteita (both in Kenya). Therefore, a new subspecies is described on the basis of morphological characters. This new subspecies shows a similar colouration in both sexes which is unique in the genus Agama. Copyright © 2010 · Magnolia Press.