@article{SchedinaPfautschHartmannetal.2014, author = {Schedina, Ina-Maria and Pfautsch, Simone and Hartmann, Stefanie and Dolgener, N. and Polgar, Anika and Bianco, Pier Giorgio and Tiedemann, Ralph and Ketmaier, Valerio}, title = {Isolation and characterization of eight microsatellite loci in the brook lamprey Lampetra planeri (Petromyzontiformes) using 454 sequence data}, series = {Journal of fish biology}, volume = {85}, journal = {Journal of fish biology}, number = {3}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0022-1112}, doi = {10.1111/jfb.12470}, pages = {960 -- 964}, year = {2014}, abstract = {Eight polymorphic microsatellite loci were developed for the brook lamprey Lampetra planeri through 454 sequencing and their usefulness was tested in 45 individuals of both L. planeri and the river lamprey Lampetra fluviatilis. The number of alleles per loci ranged between two and five; the Italian and Irish populations had a mean expected heterozygosity of 0.388 and 0.424 and a mean observed heterozygosity of 0.418 and 0.411, respectively. (C) 2014 The Fisheries Society of the British Isles}, language = {en} } @article{TebbeOttensmannHavensteinetal.2022, author = {Tebbe, Jonas and Ottensmann, Meinolf and Havenstein, Katja and Efstratiou, Artemis and Lenz, Tobias L. and Caspers, Barbara A. and Forcada, Jaume and Tiedemann, Ralph and Hoffman, Joseph}, title = {Intronic primers reveal unexpectedly high major histocompatibility complex diversity in Antarctic fur seals}, series = {Scientific reports}, volume = {12}, journal = {Scientific reports}, number = {1}, publisher = {Nature Publishing Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-022-21658-7}, pages = {14}, year = {2022}, abstract = {The major histocompatibility complex (MHC) is a group of genes comprising one of the most important components of the vertebrate immune system. Consequently, there has been much interest in characterising MHC variation and its relationship with fitness in a variety of species. Due to the exceptional polymorphism of MHC genes, careful PCR primer design is crucial for capturing all of the allelic variation present in a given species. We therefore developed intronic primers to amplify the full-length 267 bp protein-coding sequence of the MHC class II DQB exon 2 in the Antarctic fur seal. We then characterised patterns of MHC variation among mother-offspring pairs from two breeding colonies and detected 19 alleles among 771 clone sequences from 56 individuals. The distribution of alleles within and among individuals was consistent with a single-copy, classical DQB locus showing Mendelian inheritance. Amino acid similarity at the MHC was significantly associated with genome-wide relatedness, but no relationship was found between MHC heterozygosity and genome-wide heterozygosity. Finally, allelic diversity was several times higher than reported by a previous study based on partial exon sequences. This difference appears to be related to allele-specific amplification bias, implying that primer design can strongly impact the inference of MHC diversity.}, language = {en} } @article{NahavandiKetmaierTiedemann2012, author = {Nahavandi, Nahid and Ketmaier, Valerio and Tiedemann, Ralph}, title = {Intron structure of the elongation factor 1-alpha gene in the ponto-caspian amphipod pontogammarus maeoticus (Sowinsky, 1894) and its phylogeographic utility}, series = {Journal of crustacean biology}, volume = {32}, journal = {Journal of crustacean biology}, number = {3}, publisher = {Brill}, address = {San Antonio}, issn = {0278-0372}, doi = {10.1163/193724012X626584}, pages = {425 -- 433}, year = {2012}, abstract = {We tested the utility of a 230 base pair intron fragment of the highly conserved nuclear gene Elongation Factor 1-alpha (EF1-alpha) as a proper marker to reconstruct the phylogeography of the marine amphipod Pontogammarus maeoticus (Sowinsky, 1894) from the Caspian and Black Seas. As a prerequisite for further analysis, we confirmed by Southern blot analysis that EF1-alpha is encoded at a single locus in P. maeoticus. We included 15 populations and 60 individuals in the study. Both the phylogeny of the 27 unique alleles found and population genetic analyses revealed a significant differentiation between populations from the aforementioned sea basins. Our results are in remarkable agreement with recent studies on a variety of species from the same area, which invariably support a major phylogeographic break between the Caspian and Black Seas. We thus conclude that our EF1-alpha intron is an informative marker for phylogeographic studies in amphipods at the shallow population level.}, language = {en} } @article{SchwarteBrustSteupetal.2013, author = {Schwarte, Sandra and Brust, Henrike and Steup, Martin and Tiedemann, Ralph}, title = {Intraspecific sequence variation and differential expression in starch synthase genes of Arabidopsis thaliana}, doi = {10.1186/1756-0500-6-84}, year = {2013}, language = {en} } @article{KorniienkoNguyenBaumgartneretal.2020, author = {Korniienko, Yevheniia and Nguyen, Linh and Baumgartner, Stephanie and Vater, Marianne and Tiedemann, Ralph and Kirschbaum, Frank}, title = {Intragenus F1-hybrids of African weakly electric fish (Mormyridae: Campylomormyrus tamandua male x C. compressirostris female) are fertile}, series = {Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology}, volume = {206}, journal = {Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology}, number = {4}, publisher = {Springer}, address = {Heidelberg}, issn = {0340-7594}, doi = {10.1007/s00359-020-01425-7}, pages = {571 -- 585}, year = {2020}, abstract = {Hybridization is widespread in fish and constitutes an important mechanism in fish speciation. There is, however, little knowledge about hybridization in mormyrids. F1-interspecies hybrids betweenCampylomormyrus tamandua male x C. compressirostris female were investigated concerning: (1) fertility; (2) survival of F2-fish and (3) new gene combinations in the F2-generation concerning the structure of the electric organ and features of the electric organ discharge. These F1-hybrids achieved sexual maturity at about 12-13.5 cm total length. A breeding group comprising six males and 13 females spawned 28 times naturally proving these F1-fish to be fertile. On average 228 eggs were spawned, the average fertilization rate was 47.8\%. Eggs started to hatch 70-72 h after fertilization, average hatching rate was 95.6\%. Average mortality rate during embryonic development amounted to 2.3\%. Average malformation rate during the free embryonic stage was 27.7\%. Exogenous feeding started on day 11. In total, we raised 353 normally developed larvae all of which died consecutively, the oldest specimen reaching an age of 5 months. During survival, the activities of the larval and adult electric organs were recorded and the structure of the adult electric organ was investigated histologically.}, language = {en} } @article{GrossClausWohlseinetal.2020, author = {Gross, Stephanie and Claus, Philip and Wohlsein, Peter and Kesselring, Tina and Lakemeyer, Jan and Reckendorf, Anja and Roller, Marco and Tiedemann, Ralph and Siebert, Ursula}, title = {Indication of lethal interactions between a solitary bottlenose dolphin (Tursiops truncatus) and harbor porpoises (Phocoena phocoena) in the German Baltic Sea}, series = {BMC zoology}, volume = {5}, journal = {BMC zoology}, number = {1}, publisher = {BMC}, address = {London}, issn = {2056-3132}, doi = {10.1186/s40850-020-00061-7}, pages = {9}, year = {2020}, abstract = {Background Aggressive interactions between bottlenose dolphins (Tursiops truncatus) and harbor porpoises (Phocoena phocoena) have been reported in different parts of the world since the late 1990s. In the Baltic Sea, harbor porpoises are the only native cetacean species, while bottlenose dolphins may appear there temporarily. In the fall of 2016, a solitary male photo-identified bottlenose dolphin stayed in the German Baltic Sea of Schleswig-Holstein for 3 months. During that time, the necropsies of the stranded harbor porpoises revealed types of trauma of varying degrees in six animals, which is unusual in this area. The purpose of this study was to determine if the appearance of the bottlenose dolphin could be linked to the trauma of the harbor porpoise carcasses. Results Pathological findings in these animals included subcutaneous, thoracic and abdominal hemorrhages, multiple, mainly bilateral, rib fractures, and one instance of lung laceration. These findings correspond with the previously reported dolphin-caused injuries in other regions. Moreover, public sighting reports showed a spatial and temporal correlation between the appearance of the dolphin and the stranding of fatally injured harbor porpoises. Conclusion Despite the fact that no attack has been witnessed in German waters to date, our findings indicate the first record of lethal interactions between a bottlenose dolphin and harbor porpoises in the German Baltic Sea. Furthermore, to our knowledge, this is the first report of porpoise aggression by a socially isolated bottlenose dolphin.}, language = {en} } @article{MarroneHavensteinTiedemannetal.2016, author = {Marrone, F. and Havenstein, Katja and Tiedemann, Ralph and Ketmaier, V.}, title = {Identification and characterization of five polymorphic microsatellite loci in the freshwater copepod Hemidiaptomus gurneyi (Copepoda: Calanoida: Diaptomidae)}, series = {The Italian journal of zoology}, volume = {83}, journal = {The Italian journal of zoology}, publisher = {Springer}, address = {Abingdon}, issn = {1125-0003}, doi = {10.1080/11250003.2015.1126363}, pages = {146 -- 150}, year = {2016}, abstract = {Hemidiaptomus diaptomid copepods are known to be excellent biological indicators for the highly biodiverse crustacean communities inhabiting Mediterranean temporary ponds (MTPs), an endangered inland water habitat whose conservation is considered a priority according to the "Habitat Directive" of the European Union. This study reports on the characterization of five polymorphic microsatellite loci in Hemidiaptomus gurneyi, to be used as markers for fine-scale studies on the population genetic structure and metapopulation dynamics of a typical and obligate MTP dweller. The five selected loci proved to be polymorphic in the species, with three to five polymorphic loci per studied population. Overall, mean heterozygosity scored for all loci and populations was lower than that reported for the few other diaptomid species for which microsatellite loci have been to date described; this is possibly due to the intrinsically fragmented and isolated peculiar habitat inhabited by the species. Furthermore, the presence of indels within the flanking regions of selected loci was scored. This study, albeit confirming the technical difficulties in finding proper microsatellite markers in copepods, provides for the first time a set of useful polymorphic microsatellite loci for a Hemidiaptomus species, thus allowing the realization of fine-scale phylogeographic and population genetics studies of this flagship crustacean taxon for MTPs.}, language = {en} } @article{TrauthMaslinDeinoetal.2010, author = {Trauth, Martin H. and Maslin, Mark A. and Deino, Alan L. and Junginger, Annett and Lesoloyia, Moses and Odada, Eric O. and Olago, Daniel O. and Olaka, Lydia A. and Strecker, Manfred and Tiedemann, Ralph}, title = {Human evolution in a variable environment : the amplifier lakes of Eastern Africa}, issn = {0277-3791}, doi = {10.1016/j.quascirev.2010.07.007}, year = {2010}, abstract = {The development of rise Cenozoic East African Rift System (EARS) profoundly re-shaped the landscape and significantly increased the amplitude of short-term environmental response to climate variation. In particular, the development of amplifier lakes in rift basins after three million years ago significantly contributed to this exceptional sensitivity of East Africa to climate change compared to elsewhere on the African continent. Amplifier lakes are characterized by tectonically-formed graben morphologies in combination with an extreme contrast between high precipitation in the elevated parts of the catchment and high evaporation in the lake area. Such amplifier lakes respond rapidly to moderate, precessional-forced climate shifts, and as they do so apply dramatic environmental pressure to the biosphere. Rift basins, when either extremely dry or lake-filled, form important barriers for migration, mixing and competition of different populations of animals and hominins. Amplifier lakes link long-term, high-amplitude tectonic processes and short-term environmental fluctuations. East Africa may have become the place where early humans evolved as a consequence of this strong link between different time scales. (C) 2010 Elsevier Ltd. All rights reserved.}, language = {en} } @article{EppStoofTrauthetal.2010, author = {Epp, Laura Saskia and Stoof, Kathleen R. and Trauth, Martin H. and Tiedemann, Ralph}, title = {Historical genetics on a sediment core from a Kenyan lake : intraspecific genotype turnover in a tropical rotifer is related to past environmental changes}, issn = {0921-2728}, doi = {10.1007/s10933-009-9379-7}, year = {2010}, abstract = {Using molecular genetic methods and an ancient DNA approach, we studied population and species succession of rotifers of the genus Brachionus in the Kenyan alkaline-saline crater lake Sonachi since the beginning of the 19th century as well as distribution of Brachionus haplotypes in recent and historic sediments of other lakes of the East African Rift System. The sediment core record of Lake Sonachi displays haplotypes of a distinct evolutionary lineage in all increments. Populations were dominated by a single mitochondrial haplotype for a period of 150 years, and two putatively intraspecific turnovers in dominance occurred. Both changes are concordant with major environmental perturbations documented by a profound visible change in sediment composition of the core. The first change was very abrupt and occurred after the deposition of volcanic ash at the beginning of the 19th century. The second change coincides with a major lake level lowstand during the 1940s. It was preceded by a period of successively declining lake level, in which two other haplotypes appeared in the lake. One of these putatively belongs to another species documented in historical and recent Kenyan lake sediments. The analysis of plankton population dynamics through historical time can reveal patterns of population persistence and turnover in relation to environmental changes.}, language = {en} } @article{AutenriethHartmannLahetal.2018, author = {Autenrieth, Marijke and Hartmann, Stefanie and Lah, Ljerka and Roos, Anna and Dennis, Alice B. and Tiedemann, Ralph}, title = {High-quality whole-genome sequence of an abundant Holarctic odontocete, the harbour porpoise (Phocoena phocoena)}, series = {Molecular ecology resources}, volume = {18}, journal = {Molecular ecology resources}, number = {6}, publisher = {Wiley}, address = {Hoboken}, issn = {1755-098X}, doi = {10.1111/1755-0998.12932}, pages = {1469 -- 1481}, year = {2018}, abstract = {The harbour porpoise (Phocoena phocoena) is a highly mobile cetacean found across the Northern hemisphere. It occurs in coastal waters and inhabits basins that vary broadly in salinity, temperature and food availability. These diverse habitats could drive subtle differentiation among populations, but examination of this would be best conducted with a robust reference genome. Here, we report the first harbour porpoise genome, assembled de novo from an individual originating in the Kattegat Sea (Sweden). The genome is one of the most complete cetacean genomes currently available, with a total size of 2.39 Gb and 50\% of the total length found in just 34 scaffolds. Using 122 of the longest scaffolds, we were able to show high levels of synteny with the genome of the domestic cattle (Bos taurus). Our draft annotation comprises 22,154 predicted genes, which we further annotated through matches to the NCBI nucleotide database, GO categorization and motif prediction. Within the predicted genes, we have confirmed the presence of >20 genes or gene families that have been associated with adaptive evolution in other cetaceans. Overall, this genome assembly and draft annotation represent a crucial addition to the genomic resources currently available for the study of porpoises and Phocoenidae evolution, phylogeny and conservation.}, language = {en} } @article{StoofLeichsenringEppTrauthetal.2012, author = {Stoof-Leichsenring, Kathleen Rosemarie and Epp, Laura Saskia and Trauth, Martin H. and Tiedemann, Ralph}, title = {Hidden diversity in diatoms of Kenyan Lake Naivasha a genetic approach detects temporal variation}, series = {Molecular ecology}, volume = {21}, journal = {Molecular ecology}, number = {8}, publisher = {Wiley-Blackwell}, address = {Malden}, issn = {0962-1083}, doi = {10.1111/j.1365-294X.2011.05412.x}, pages = {1918 -- 1930}, year = {2012}, abstract = {This study provides insights into the morphological and genetic diversity in diatoms occurring in core sediments from tropical lakes in Kenya. We developed a genetic survey technique specific for diatoms utilizing a short region (7667 bp) of the ribulose-1,5-bisphosphate carboxylase/oxygenase large subunit (rbcL) gene as genetic barcode. Our analyses (i) validated the use of rbcL as a barcoding marker for diatoms, applied to sediment samples, (ii) showed a significant correlation between the results obtained by morphological and molecular data and (iii) indicated temporal variation in diatom assemblages on the inter- and intra-specific level. Diatom assemblages from a short core from Lake Naivasha show a drastic shift over the last 200 years, as littoral species (e.g. Navicula) are replaced by more planktonic ones (e.g. Aulacoseira). Within that same period, we detected periodic changes in the respective frequencies of distinct haplotype groups of Navicula, which coincide with wet and dry periods of Lake Naivasha between 1820 and 1938 AD. Our genetic analyses on historical lake sediments revealed inter- and intra-specific variation in diatoms, which is partially hidden behind single morphotypes. The occurrence of particular genetic lineages is probably correlated with environmental factors.}, language = {en} } @article{CahsanWestburyParaskevopoulouetal.2021, author = {Cahsan, Binia De and Westbury, Michael V. and Paraskevopoulou, Sofia and Drews, Hauke and Ott, Moritz and Gollmann, G{\"u}nter and Tiedemann, Ralph}, title = {Genomic consequences of human-mediated translocations in margin populations of an endangered amphibian}, series = {Evolutionary Applications}, volume = {14}, journal = {Evolutionary Applications}, number = {6}, publisher = {John Wiley \& Sons, Inc.}, address = {New Jersey}, issn = {1752-4563}, doi = {10.1111/eva.13229}, pages = {12}, year = {2021}, abstract = {Due to their isolated and often fragmented nature, range margin populations are especially vulnerable to rapid environmental change. To maintain genetic diversity and adaptive potential, gene flow from disjunct populations might therefore be crucial to their survival. Translocations are often proposed as a mitigation strategy to increase genetic diversity in threatened populations. However, this also includes the risk of losing locally adapted alleles through genetic swamping. Human-mediated translocations of southern lineage specimens into northern German populations of the endangered European fire-bellied toad (Bombina bombina) provide an unexpected experimental set-up to test the genetic consequences of an intraspecific introgression from central population individuals into populations at the species range margin. Here, we utilize complete mitochondrial genomes and transcriptome nuclear data to reveal the full genetic extent of this translocation and the consequences it may have for these populations. We uncover signs of introgression in four out of the five northern populations investigated, including a number of introgressed alleles ubiquitous in all recipient populations, suggesting a possible adaptive advantage. Introgressed alleles dominate at the MTCH2 locus, associated with obesity/fat tissue in humans, and the DSP locus, essential for the proper development of epidermal skin in amphibians. Furthermore, we found loci where local alleles were retained in the introgressed populations, suggesting their relevance for local adaptation. Finally, comparisons of genetic diversity between introgressed and nonintrogressed northern German populations revealed an increase in genetic diversity in all German individuals belonging to introgressed populations, supporting the idea of a beneficial transfer of genetic variation from Austria into North Germany.}, language = {en} } @article{SharmaStuckasBhaskaretal.2011, author = {Sharma, Reeta and Stuckas, Heiko and Bhaskar, Ranjana and Khan, Imran and Goyal, Surendra Prakash and Tiedemann, Ralph}, title = {Genetically distinct population of Bengal tiger (Panthera tigris tigris) in Terai Arc Landscape (TAL) of India}, series = {Mammalian biology = Zeitschrift f{\"u}r S{\"a}ugetierkunde}, volume = {76}, journal = {Mammalian biology = Zeitschrift f{\"u}r S{\"a}ugetierkunde}, number = {4}, publisher = {Elsevier}, address = {Jena}, issn = {1616-5047}, doi = {10.1016/j.mambio.2010.10.005}, pages = {484 -- 490}, year = {2011}, abstract = {We analyzed mtDNA polymorphisms (a total of 741 bp from a part of conserved control region, ND5, ND2, Cyt b and 12S) in 91 scats and 12 tissue samples of Bengal tiger (Panthera tigris tigris) populations across Terai Arc Landscape (TAL) located at the foothills of Himalayas in North Western India, Buxa Tiger Reserve (BTR), and North East India. In TAL and BTR, we found a specific haplotype at high frequency, which was absent elsewhere, indicating a genetically distinct population in these regions. Within the TAL region, there is some evidence for genetic isolation of the tiger populations west of river Ganges, i.e., in the western part of Rajaji National Park (RNP). Although the river itself might not constitute a significant barrier for tigers, recent human-induced changes in habitat and degradation of the Motichur-Chilla Corridor connecting the two sides of the tiger habitat of RNP might effectively prevent genetic exchange. A cohesive population is observed for the rest of the TAL. Even the more eastern BTR belongs genetically to this unit, despite the present lack of a migration corridor between BTR and TAL. In spite of a close geographic proximity, Chitwan (Nepal) constitutes a tiger population genetically different from TAL. Moreover, it is observed that the North East India tiger populations are genetically different from TAL and BTR, as well as from the other Bengal tiger populations in India.}, language = {en} } @article{DominguezTiedemannReboredaetal.2017, author = {Dominguez, Marisol and Tiedemann, Ralph and Reboreda, Juan C. and Segura, Luciano and Tittarelli, Fabian and Mahler, Bettina}, title = {Genetic structure reveals management units for the yellow cardinal (Gubernatrix cristata), endangered by habitat loss and illegal trapping}, series = {Conservation genetics}, volume = {18}, journal = {Conservation genetics}, publisher = {Springer}, address = {Dordrecht}, issn = {1566-0621}, doi = {10.1007/s10592-017-0964-4}, pages = {1131 -- 1140}, year = {2017}, language = {en} } @article{DolgenerSchroederSchneeweissetal.2012, author = {Dolgener, Nicola and Schr{\"o}der, Christiane and Schneeweiss, N. and Tiedemann, Ralph}, title = {Genetic population structure of the Fire-bellied toad Bombina bombina in an area of high population density implications for conservation}, series = {Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica}, volume = {689}, journal = {Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica}, number = {1}, publisher = {Springer}, address = {Dordrecht}, issn = {0018-8158}, doi = {10.1007/s10750-012-1016-1}, pages = {111 -- 120}, year = {2012}, abstract = {In this study, we report the genetic population structure of the Fire-bellied toad Bombina bombina in Brandenburg (East Germany) in the context of conservation. We analysed 298 samples originating from 11 populations in Brandenburg using mitochondrial control region sequences and six polymorphic microsatellite loci. For comparison, we included one population each from Poland and Ukraine into our analysis. Within Brandenburg, we detected a moderate variability in the mitochondrial control region (19 different haplotypes) and at microsatellite loci (9-12 alleles per locus). These polymorphisms revealed a clear population structure among toads in Brandenburg, despite a relatively high overall population density and the moderate size of single populations (100-2000 individuals). The overall genetic population structure is consistent with a postglacial colonization from South East-Europe and a subsequent population expansion. Based on genetic connectivity, we infer Management Units (MUs) as targets for conservation. Our genetic survey identified MUs, within which human infrastructure is currently preventing any genetic exchange. We also detect an unintentional translocation from South East to North West Brandenburg, presumably in the course of fish stocking activities. Provided suitable conservation measures are taken, Brandenburg should continue to harbor large populations of this critically endangered species.}, language = {en} } @article{StoofLeichsenringHerzschuhPestryakovaetal.2015, author = {Stoof-Leichsenring, Kathleen Rosemarie and Herzschuh, Ulrike and Pestryakova, Luidmila Agafyevna and Klemm, Juliane and Epp, Laura Saskia and Tiedemann, Ralph}, title = {Genetic data from algae sedimentary DNA reflect the influence of environment over geography}, series = {Scientific reports}, volume = {5}, journal = {Scientific reports}, publisher = {Nature Publ. Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/srep12924}, pages = {11}, year = {2015}, abstract = {Genetic investigations on eukaryotic plankton confirmed the existence of modern biogeographic patterns, but analyses of palaeoecological data exploring the temporal variability of these patterns have rarely been presented. Ancient sedimentary DNA proved suitable for investigations of past assemblage turnover in the course of environmental change, but genetic relatedness of the identified lineages has not yet been undertaken. Here, we investigate the relatedness of diatom lineages in Siberian lakes along environmental gradients (i.e. across treeline transects), over geographic distance and through time (i.e. the last 7000 years) using modern and ancient sedimentary DNA. Our results indicate that closely-related Staurosira lineages occur in similar environments and less-related lineages in dissimilar environments, in our case different vegetation and co-varying climatic and limnic variables across treeline transects. Thus our study reveals that environmental conditions rather than geographic distance is reflected by diatom-relatedness patterns in space and time. We tentatively speculate that the detected relatedness pattern in Staurosira across the treeline could be a result of adaptation to diverse environmental conditions across the arctic boreal treeline, however, a geographically-driven divergence and subsequent repopulation of ecologically different habitats might also be a potential explanation for the observed pattern.}, language = {en} } @article{PavesiTiedemannDeMatthaeisetal.2013, author = {Pavesi, Laura and Tiedemann, Ralph and DeMatthaeis, Elvira and Ketmaier, Valerio}, title = {Genetic connectivity between land and sea: the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea}, issn = {1742-9994}, year = {2013}, language = {en} } @article{PavesiTiedemannDeMatthaeisetal.2013, author = {Pavesi, Laura and Tiedemann, Ralph and De Matthaeis, Elvira and Ketmaier, Valerio}, title = {Genetic connectivity between land and sea - the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea}, series = {Frontiers in zoology}, volume = {10}, journal = {Frontiers in zoology}, number = {4-5}, publisher = {BioMed Central}, address = {London}, issn = {1742-9994}, doi = {10.1186/1742-9994-10-21}, pages = {19}, year = {2013}, abstract = {Introduction: We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces. Results: Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set. Conclusions: We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism.}, language = {en} } @article{MilinkovitchMonteyneGibbsetal.2004, author = {Milinkovitch, M. C. and Monteyne, D. and Gibbs, J. P. and Fritts, T. H. and Tapia, W. and Snell, H. L. and Tiedemann, Ralph and Caccone, Adalgisa and Powell, J. R.}, title = {Genetic analysis of a successful repatriation programme : giant Galapagos tortoises}, issn = {0962-8452}, year = {2004}, abstract = {As natural populations of endangered species dwindle to precarious levels, remaining members are sometimes brought into captivity, allowed to breed and their offspring returned to the natural habitat. One goal of such repatriation programmes is to retain as much of the genetic variation of the species as possible. A taxon of giant GalApagos tortoises on the island of Espahola has been the subject of a captive breeding-repatriation programme for 33 years. Core breeders, consisting of 12 females and three males, have produced more than 1200 offspring that have been released on Espanola where in situ reproduction has recently been observed. Using microsatellite DNA markers, we have determined the maternity and paternity of 132 repatriated offspring. Contributions of the breeders are highly skewed. This has led to a further loss of genetic variation that is detrimental to the long-term survival of the population. Modifications to the breeding programme could alleviate this problem}, language = {en} } @article{SammlerBleidornTiedemann2011, author = {Sammler, Svenja and Bleidorn, Christoph and Tiedemann, Ralph}, title = {Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae) provide evidence for pervasive mitochondrial DNA recombination}, series = {BMC genomics}, volume = {12}, journal = {BMC genomics}, number = {2}, publisher = {BioMed Central}, address = {London}, issn = {1471-2164}, doi = {10.1186/1471-2164-12-35}, pages = {10}, year = {2011}, abstract = {Background: Although nowaday it is broadly accepted that mitochondrial DNA (mtDNA) may undergo recombination, the frequency of such recombination remains controversial. Its estimation is not straightforward, as recombination under homoplasmy (i.e., among identical mt genomes) is likely to be overlooked. In species with tandem duplications of large mtDNA fragments the detection of recombination can be facilitated, as it can lead to gene conversion among duplicates. Although the mechanisms for concerted evolution in mtDNA are not fully understood yet, recombination rates have been estimated from "one per speciation event" down to 850 years or even "during every replication cycle". Results: Here we present the first complete mt genome of the avian family Bucerotidae, i.e., that of two Philippine hornbills, Aceros waldeni and Penelopides panini. The mt genomes are characterized by a tandemly duplicated region encompassing part of cytochrome b, 3 tRNAs, NADH6, and the control region. The duplicated fragments are identical to each other except for a short section in domain I and for the length of repeat motifs in domain III of the control region. Due to the heteroplasmy with regard to the number of these repeat motifs, there is some size variation in both genomes; with around 21,657 bp (A. waldeni) and 22,737 bp (P. panini), they significantly exceed the hitherto longest known avian mt genomes, that of the albatrosses. We discovered concerted evolution between the duplicated fragments within individuals. The existence of differences between individuals in coding genes as well as in the control region, which are maintained between duplicates, indicates that recombination apparently occurs frequently, i. e., in every generation. Conclusions: The homogenised duplicates are interspersed by a short fragment which shows no sign of recombination. We hypothesize that this region corresponds to the so-called Replication Fork Barrier (RFB), which has been described from the chicken mitochondrial genome. As this RFB is supposed to halt replication, it offers a potential mechanistic explanation for frequent recombination in mitochondrial genomes.}, language = {en} } @article{SammlerHavensteinTiedemann2012, author = {Sammler, Svenja and Havenstein, Katja and Tiedemann, Ralph}, title = {Fourteen new microsatellite markers for the Visayan tarictic hornbill (Penelopides panini) and their cross-species applicability among other endangered Philippine hornbills}, series = {Conservation genetics resources}, volume = {4}, journal = {Conservation genetics resources}, number = {2}, publisher = {Springer}, address = {Dordrecht}, issn = {1877-7252}, doi = {10.1007/s12686-011-9567-4}, pages = {435 -- 438}, year = {2012}, abstract = {Fourteen microsatellite markers were isolated and characterized for the endangered Visayan tarictic hornbill (Penelopides panini, Aves: Bucerotidae). In an analysis of 76 individuals, the number of alleles per locus varied from one to 12. Expected and observed heterozygosity ranged from 0.00 to 0.87 and from 0.00 to 0.89, respectively. All primers also amplify microsatellite loci in Luzon tarictic hornbill (Penelopides manillae), Mindanao tarictic hornbill (Penelopides affinis), the critically endangered Walden's hornbill (Aceros waldeni) and the near-threatened writhed hornbill (Aceros leucocephalus). Two loci which are monomorphic in P. panini were found polymorphic in at least one of the other species. These 14 new microsatellite markers specifically developed for two genera of Philippine hornbills, in combination with those already available for the hornbill genera Buceros and Bucorvus, comprise a reasonable number of loci to genetically analyse wild and captive populations of these and probably other related, often endangered hornbills.}, language = {en} } @article{ReckendorfLudesWehrmeisterWohlseinetal.2018, author = {Reckendorf, Anja and Ludes-Wehrmeister, Eva and Wohlsein, Peter and Tiedemann, Ralph and Siebert, U. and Lehnert, Kristina}, title = {First record of Halocercus sp (Pseudaliidae) lungworm infections in two stranded neonatal orcas (Orcinus orca)}, series = {Parasitology}, volume = {145}, journal = {Parasitology}, number = {12}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {0031-1820}, doi = {10.1017/S0031182018000586}, pages = {1553 -- 1557}, year = {2018}, abstract = {Orca (Orcinus orca) strandings are rare and post-mortem examinations on fresh individuals are scarce. Thus, little is known about their parasitological fauna, prevalence of infections, associated pathology and the impact on their health. During post-mortem examinations of two male neonatal orcas stranded in Germany and Norway, lungworm infections were found within the bronchi of both individuals. The nematodes were identified as Halocercus sp. (Pseudaliidae), which have been described in the respiratory tract of multiple odontocete species, but not yet in orcas. The life cycle and transmission pathways of some pseudaliid nematodes are incompletely understood. Lungworm infections in neonatal cetaceans are an unusual finding and thus seem to be an indicator for direct mother-to-calf transmission (transplacental or transmammary) of Halocercus sp. nematodes in orcas.}, language = {en} } @article{ApioKabasaKetmaieretal.2010, author = {Apio, Ann and Kabasa, John David and Ketmaier, Valerio and Schroeder, Christoph and Plath, Martin and Tiedemann, Ralph}, title = {Female philopatry and male dispersal in a cryptic, bush-dwelling antelope : a combined molecular and behavioural approach}, issn = {0952-8369}, doi = {10.1111/j.1469-7998.2009.00654.x}, year = {2010}, abstract = {In most mammals, females are philopatric while males disperse in order to avoid inbreeding. We investigated social structure in a solitary ungulate, the bushbuck Tragelaphus sylvaticus in Queen Elizabeth National Park, Uganda by combining behavioural and molecular data. We correlated spatial and social vicinity of individual females with a relatedness score obtained from mitochondrial DNA analysis. Presumed clan members shared the same haplotype, showed more socio-positive interactions and had a common home range. Males had a higher haplotype diversity than females. All this suggests the presence of a matrilineal structure in the study population. Moreover, we tested natal dispersal distances between male and female yearlings and used control region sequences to confirm that females remain in their natal breeding areas whereas males disperse. In microsatellite analysis, males showed a higher genetic variability than females. The impoverished genetic variability of females at both molecular marker sets is consistent with a philopatric and matrilineal structure, while the higher degree of genetic variability of males is congruent with a higher dispersal rate expected in this sex. Evidence even for male long-distance dispersal is brought about by one male carrying a haplotype of a different subspecies, previously not described to occur in this area.}, language = {en} } @article{KruegerFoersterTrauthetal.2021, author = {Kr{\"u}ger, Johanna and Foerster, Verena Elisabeth and Trauth, Martin H. and Hofreiter, Michael and Tiedemann, Ralph}, title = {Exploring the Past Biosphere of Chew Bahir/Southern Ethiopia: Cross-Species Hybridization Capture of Ancient Sedimentary DNA from a Deep Drill Core}, series = {Frontiers in Earth Science}, journal = {Frontiers in Earth Science}, publisher = {Frontiers in Earth Science}, address = {Lausanne, Schweiz}, issn = {2296-6463}, doi = {10.3389/feart.2021.683010}, pages = {1 -- 20}, year = {2021}, abstract = {Eastern Africa has been a prime target for scientific drilling because it is rich in key paleoanthropological sites as well as in paleolakes, containing valuable paleoclimatic information on evolutionary time scales. The Hominin Sites and Paleolakes Drilling Project (HSPDP) explores these paleolakes with the aim of reconstructing environmental conditions around critical episodes of hominin evolution. Identification of biological taxa based on their sedimentary ancient DNA (sedaDNA) traces can contribute to understand past ecological and climatological conditions of the living environment of our ancestors. However, sedaDNA recovery from tropical environments is challenging because high temperatures, UV irradiation, and desiccation result in highly degraded DNA. Consequently, most of the DNA fragments in tropical sediments are too short for PCR amplification. We analyzed sedaDNA in the upper 70 m of the composite sediment core of the HSPDP drill site at Chew Bahir for eukaryotic remnants. We first tested shotgun high throughput sequencing which leads to metagenomes dominated by bacterial DNA of the deep biosphere, while only a small fraction was derived from eukaryotic, and thus probably ancient, DNA. Subsequently, we performed cross-species hybridization capture of sedaDNA to enrich ancient DNA (aDNA) from eukaryotic remnants for paleoenvironmental analysis, using established barcoding genes (cox1 and rbcL for animals and plants, respectively) from 199 species that may have had relatives in the past biosphere at Chew Bahir. Metagenomes yielded after hybridization capture are richer in reads with similarity to cox1 and rbcL in comparison to metagenomes without prior hybridization capture. Taxonomic assignments of the reads from these hybridization capture metagenomes also yielded larger fractions of the eukaryotic domain. For reads assigned to cox1, inferred wet periods were associated with high inferred relative abundances of putative limnic organisms (gastropods, green algae), while inferred dry periods showed increased relative abundances for insects. These findings indicate that cross-species hybridization capture can be an effective approach to enhance the information content of sedaDNA in order to explore biosphere changes associated with past environmental conditions, enabling such analyses even under tropical conditions.}, language = {en} } @article{HartmannHelmNickeletal.2012, author = {Hartmann, Stefanie and Helm, Conrad and Nickel, Birgit and Meyer, Matthias and Struck, Torsten H. and Tiedemann, Ralph and Selbig, Joachim and Bleidorn, Christoph}, title = {Exploiting gene families for phylogenomic analysis of myzostomid transcriptome data}, series = {PLoS one}, volume = {7}, journal = {PLoS one}, number = {1}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0029843}, pages = {8}, year = {2012}, abstract = {Background: In trying to understand the evolutionary relationships of organisms, the current flood of sequence data offers great opportunities, but also reveals new challenges with regard to data quality, the selection of data for subsequent analysis, and the automation of steps that were once done manually for single-gene analyses. Even though genome or transcriptome data is available for representatives of most bilaterian phyla, some enigmatic taxa still have an uncertain position in the animal tree of life. This is especially true for myzostomids, a group of symbiotic ( or parasitic) protostomes that are either placed with annelids or flatworms. Methodology: Based on similarity criteria, Illumina-based transcriptome sequences of one myzostomid were compared to protein sequences of one additional myzostomid and 29 reference metazoa and clustered into gene families. These families were then used to investigate the phylogenetic position of Myzostomida using different approaches: Alignments of 989 sequence families were concatenated, and the resulting superalignment was analyzed under a Maximum Likelihood criterion. We also used all 1,878 gene trees with at least one myzostomid sequence for a supertree approach: the individual gene trees were computed and then reconciled into a species tree using gene tree parsimony. Conclusions: Superalignments require strictly orthologous genes, and both the gene selection and the widely varying amount of data available for different taxa in our dataset may cause anomalous placements and low bootstrap support. In contrast, gene tree parsimony is designed to accommodate multilocus gene families and therefore allows a much more comprehensive data set to be analyzed. Results of this supertree approach showed a well-resolved phylogeny, in which myzostomids were part of the annelid radiation, and major bilaterian taxa were found to be monophyletic.}, language = {en} } @article{StuckasStoofQuesadaetal.2009, author = {Stuckas, Heiko and Stoof, Kathleen and Quesada, Humberto and Tiedemann, Ralph}, title = {Evolutionary implications of discordant clines across the Baltic Mytilus hybrid zone (Mytilus edulis and Mytilus trossulus)}, issn = {0018-067X}, doi = {10.1038/Hdy.2009.37}, year = {2009}, abstract = {It is well established that reproductive isolation often arises from genome incompatibilities and that genes encoding reproductive traits are less prone to introgression. Hybrid zones of Mytilus trossulus and Mytilus edulis provide an intriguing model to assess reproductive isolation. Although gene flow is restricted in North America, introgression is pervasive in the Baltic. This study aimed at analyzing the shape of multilocus clines across the Baltic contact zone between M. edulis and M. trossulus to infer mechanisms of restriction to gene flow. We use maximum likelihood methods to construct the best fitting individual clines for five markers located on biparentally inherited autosomes and paternally and maternally inherited mitochondrial DNA (mtDNA). Strong cline shape differences among markers suggest that reproductive isolation arising from genome-wide incompatibilities is weak, and that these discrepancies possibly result from genetic drift, hybrid zone movement or marker-specific selection. However, the finding of a common cline center for M7 lysin (involved in fertilization) and paternally transmitted mtDNA (causing nuclear-mitochondrial incompatibilities in hybrids) suggest that these loci may play a role in incomplete reproductive isolation.}, language = {en} } @article{PaulKirschbaumMamonekeneetal.2016, author = {Paul, Christiane and Kirschbaum, Frank and Mamonekene, Victor and Tiedemann, Ralph}, title = {Evidence for Non-neutral Evolution in a Sodium Channel Gene in African Weakly Electric Fish (Campylomormyrus, Mormyridae)}, series = {Journal of molecular evolution}, volume = {83}, journal = {Journal of molecular evolution}, publisher = {Springer}, address = {New York}, issn = {0022-2844}, doi = {10.1007/s00239-016-9754-8}, pages = {61 -- 77}, year = {2016}, abstract = {Voltage-gated sodium channels, Nav1, play a crucial role in the generation and propagation of action potentials and substantially contribute to the shape of their rising phase. The electric organ discharge (EOD) of African weakly electric fish (Mormyroidea) is the sum of action potentials fired from all electrocytes of the electric organ at the same time and hence voltage-gated sodium channels are one factor—together with the electrocyte's morphology and innervation pattern—that determines the properties of these EODs. Due to the fish-specific genome duplication, teleost fish possess eight copies of sodium channel genes (SCN), which encode for Nav1 channels. In mormyroids, SCN4aa is solely expressed in the electrocytes of the adult electric organ. In this study, we compared entire SCN4aa sequences of six species of the genus Campylomormyrus and identified nonsynonymous substitutions among them. SCN4aa in Campylomormyrus exhibits a much higher evolutionary rate compared to its paralog SCN4ab, whose expression is not restricted to the electric organ. We also found evidence for strong positive selection on the SCN4aa gene within Mormyridae and along the lineage ancestral to the Mormyridae. We have identified sites at which all nonelectric teleosts are monomorphic in their amino acid, but mormyrids have different amino acids. Our findings confirm the crucial role of SCN4aa in EOD evolution among mormyrid weakly electric fish. The inferred positive selection within Mormyridae makes this gene a prime candidate for further investigation of the divergent evolution of pulse-type EODs among closely related species.}, language = {en} } @article{ValenteIlleraHavensteinetal.2017, author = {Valente, Luis and Illera, Juan Carlos and Havenstein, Katja and Pallien, Tamara and Etienne, Rampal S. and Tiedemann, Ralph}, title = {Equilibrium Bird Species Diversity in Atlantic Islands}, series = {Current biology}, volume = {27}, journal = {Current biology}, publisher = {Cell Press}, address = {Cambridge}, issn = {0960-9822}, doi = {10.1016/j.cub.2017.04.053}, pages = {1660 -- +}, year = {2017}, language = {en} } @article{StoofLeichsenringJungingerOlakaetal.2011, author = {Stoof-Leichsenring, Kathleen Rosemarie and Junginger, Annett and Olaka, Lydia A. and Tiedemann, Ralph and Trauth, Martin H.}, title = {Environmental variability in Lake Naivasha, Kenya, over the last two centuries}, series = {Journal of paleolimnolog}, volume = {45}, journal = {Journal of paleolimnolog}, number = {3}, publisher = {Springer}, address = {Dordrecht}, issn = {0921-2728}, doi = {10.1007/s10933-011-9502-4}, pages = {353 -- 367}, year = {2011}, abstract = {Lake Naivasha, Kenya, is one of a number of freshwater lakes in the East African Rift System. Since the beginning of the twentieth century, it has experienced greater anthropogenic influence as a result of increasingly intensive farming of coffee, tea, flowers, and other horticultural crops within its catchment. The water-level history of Lake Naivasha over the past 200 years was derived from a combination of instrumental records and sediment data. In this study, we analysed diatoms in a lake sediment core to infer past lacustrine conductivity and total phosphorus concentrations. We also measured total nitrogen and carbon concentrations in the sediments. Core chronology was established by (210)Pb dating and covered a similar to 186-year history of natural (climatic) and human-induced environmental changes. Three stratigraphic zones in the core were identified using diatom assemblages. There was a change from littoral/epiphytic diatoms such as Gomphonema gracile and Cymbella muelleri, which occurred during a prolonged dry period from ca. 1820 to 1896 AD, through a transition period, to the present planktonic Aulacoseira sp. that favors nutrient-rich waters. This marked change in the diatom assemblage was caused by climate change, and later a strong anthropogenic overprint on the lake system. Increases in sediment accumulation rates since 1928, from 0.01 to 0.08 g cm(-2) year(-1) correlate with an increase in diatom-inferred total phosphorus concentrations since the beginning of the twentieth century. The increase in phosphorus accumulation suggests increasing eutrophication of freshwater Lake Naivasha. This study identified two major periods in the lake's history: (1) the period from 1820 to 1950 AD, during which the lake was affected mainly by natural climate variations, and (2) the period since 1950, during which the effects of anthropogenic activity overprinted those of natural climate variation.}, language = {en} } @article{DolgenerFreudenbergerSchlucketal.2014, author = {Dolgener, N. and Freudenberger, L. and Schluck, M. and Schneeweiss, N. and Ibisch, P. L. and Tiedemann, Ralph}, title = {Environmental niche factor analysis (ENFA) relates environmental parameters to abundance and genetic diversity in an endangered amphibian, the fire-bellied-toad (Bombina bombina)}, series = {Conservation genetics}, volume = {15}, journal = {Conservation genetics}, number = {1}, publisher = {Springer}, address = {Dordrecht}, issn = {1566-0621}, doi = {10.1007/s10592-013-0517-4}, pages = {11 -- 21}, year = {2014}, abstract = {Increasing attempts are made to understand the factors responsible for both the demographic and genetic depletion in amphibian populations. Landscape genetics aims at a spatially explicit correlation of genetic population parameters to landscape features. Using data from the endangered fire-bellied toad Bombina bombina in Brandenburg (Northeastern Germany), we performed an environmental niche factor analysis (ENFA), relating demographic (abundance) and genetic (diversity at 17 microsatellite loci and partial sequences of the mitochondrial control region in 434 individuals from 16 populations) parameters to ecological and anthropogenic variables such as temperature, precipitation, soil wetness, water runoff, vegetation density, and road/traffic impact. We found significant correlations between road disturbance and observed heterozygosity and between soil wetness and mitochondrial diversity. As the influences of the environmental variables can differ between different indicators for genetic diversity, population size and abundance data, our ENFA-based landscape genetics approach allows us to put various aspects of long- versus short term effective population size and genetic connectivity into an ecological and spatially explicit context, enabling potentially even forecast assessment under future environmental scenarios.}, language = {en} } @article{RomeroMujalliJeltschTiedemann2019, author = {Romero-Mujalli, Daniel and Jeltsch, Florian and Tiedemann, Ralph}, title = {Elevated mutation rates are unlikely to evolve in sexual species, not even under rapid environmental change}, series = {BMC Evolutionary Biology}, volume = {19}, journal = {BMC Evolutionary Biology}, publisher = {BioMed Central}, address = {London}, issn = {1471-2148}, doi = {10.1186/s12862-019-1494-0}, pages = {9}, year = {2019}, abstract = {Background Organisms are expected to respond to changing environmental conditions through local adaptation, range shift or local extinction. The process of local adaptation can occur by genetic changes or phenotypic plasticity, and becomes especially relevant when dispersal abilities or possibilities are somehow constrained. For genetic changes to occur, mutations are the ultimate source of variation and the mutation rate in terms of a mutator locus can be subject to evolutionary change. Recent findings suggest that the evolution of the mutation rate in a sexual species can advance invasion speed and promote adaptation to novel environmental conditions. Following this idea, this work uses an individual-based model approach to investigate if the mutation rate can also evolve in a sexual species experiencing different conditions of directional climate change, under different scenarios of colored stochastic environmental noise, probability of recombination and of beneficial mutations. The color of the noise mimicked investigating the evolutionary dynamics of the mutation rate in different habitats. Results The results suggest that the mutation rate in a sexual species experiencing directional climate change scenarios can evolve and reach relatively high values mainly under conditions of complete linkage of the mutator locus and the adaptation locus. In contrast, when they are unlinked, the mutation rate can slightly increase only under scenarios where at least 50\% of arising mutations are beneficial and the rate of environmental change is relatively fast. This result is robust under different scenarios of stochastic environmental noise, which supports the observation of no systematic variation in the mutation rate among organisms experiencing different habitats. Conclusions Given that 50\% beneficial mutations may be an unrealistic assumption, and that recombination is ubiquitous in sexual species, the evolution of an elevated mutation rate in a sexual species experiencing directional climate change might be rather unlikely. Furthermore, when the percentage of beneficial mutations and the population size are small, sexual species (especially multicellular ones) producing few offspring may be expected to react to changing environments not by adaptive genetic change, but mainly through plasticity. Without the ability for a plastic response, such species may become - at least locally - extinct.}, language = {en} } @article{FeulnerKirschbaumSchugardtetal.2006, author = {Feulner, Philine G. D. and Kirschbaum, Frank and Schugardt, Christian and Ketmaier, Valerio and Tiedemann, Ralph}, title = {Electrophysiological and molecular genetic evidence for sympatrically occuring cryptic species in African weakly electric fishes (Teleostei : Mormyridae : Campylomormyrus)}, issn = {1055-7903}, doi = {10.1016/j.ympev.2005.09.008}, year = {2006}, abstract = {For two sympatric species of African weakly electric fish, Campylomormyrus tamandua and Campylomormyrus numenius, we monitored ontogenetic differentiation in electric organ discharge (EOD) and established a molecular phylogeny, based on 2222 bp from cytochrome b, the S7 ribosomal protein gene, and four flanking regions of unlinked microsatellite loci. In C tamandua, there is one common EOD type, regardless of age and sex, whereas in C numenius we were able to identify three different male adult EOD waveform types, which emerged from a single common EOD observed in juveniles. Two of these EOD types formed well supported clades in our phylogenetic analysis. In an independent line of evidence, we were able to affirm the classification into three groups by microsatellite data. The correct assignment and the high pairwise FST values support our hypothesis that these groups are reproductively isolated. We propose that in C numenius there are cryptic species, hidden behind similar and, at least as juveniles, identical morphs.}, language = {en} } @article{FeulnerPlathEngelmannetal.2009, author = {Feulner, Philine G. D. and Plath, Martin and Engelmann, Jacob and Kirschbaum, Frank and Tiedemann, Ralph}, title = {Electrifying love : electric fish use species-specific discharge for mate recognition}, issn = {1744-9561}, doi = {10.1098/rsbl.2008.0566}, year = {2009}, abstract = {Mate choice is mediated by a range of sensory cues, and assortative mating based on these cues can drive reproductive isolation among diverging populations. A specific feature of mormyrid fish, the electric organ discharge (EOD), is used for electrolocation and intraspecific communication. We hypothesized that the EOD also facilitates assortative mating and ultimately promotes prezygotic reproductive isolation in African weakly electric fishes. Our behavioural experiments using live males as well as EOD playback demonstrated that female mate recognition is influenced by EOD signals and that females are attracted to EOD characteristics of conspecific males. The dual function of the EOD for both foraging and social communication (including mate recognition leading to assortative mating) underlines the importance of electric signal differentiation for the divergence of African weakly electric fishes. Thus, the EOD provides an intriguing mechanism promoting trophic divergence and reproductive isolation between two closely related Campylomormyrus species occurring in sympatry in the lower Congo rapids.}, language = {en} } @article{NagelKirschbaumHofmannetal.2018, author = {Nagel, Rebecca and Kirschbaum, Frank and Hofmann, Volker and Engelmann, Jacob and Tiedemann, Ralph}, title = {Electric pulse characteristics can enable species recognition in African weakly electric fish species}, series = {Scientific Reports}, volume = {8}, journal = {Scientific Reports}, publisher = {Nature Publishing Group}, address = {London}, issn = {2045-2322}, doi = {10.1038/s41598-018-29132-z}, pages = {1 -- 12}, year = {2018}, abstract = {Communication is key to a wide variety of animal behaviours and multiple modalities are often involved in this exchange of information from sender to receiver. The communication of African weakly electric fish, however, is thought to be predominantly unimodal and is mediated by their electric sense, in which species-specific electric organ discharges (EODs) are generated in a context-dependent and thus variable sequence of pulse intervals (SPI). While the primary function of the electric sense is considered to be electrolocation, both of its components likely carry information regarding identity of the sender. However, a clear understanding of their contribution to species recognition is incomplete. We therefore analysed these two electrocommunication components (EOD waveform and SPI statistics) in two sympatric mormyrid Campylomormyrus species. In a set of five playback conditions, we further investigated which components may drive interspecific recognition and discrimination. While we found that both electrocommunication components are species-specific, the cues necessary for species recognition differ between the two species studied. While the EOD waveform and SPI were both necessary and sufficient for species recognition in C. compressirostris males, C. tamandua males apparently utilize other, non-electric modalities. Mapped onto a recent phylogeny, our results suggest that discrimination by electric cues alone may be an apomorphic trait evolved during a recent radiation in this taxon.}, language = {en} } @article{NagelKirschbaumTiedemann2017, author = {Nagel, Rebecca and Kirschbaum, Frank and Tiedemann, Ralph}, title = {Electric organ discharge diversification in mormyrid weakly electric fish is associated with differential expression of voltage-gated ion channel genes}, series = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, volume = {203}, journal = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, publisher = {Springer}, address = {New York}, issn = {0340-7594}, doi = {10.1007/s00359-017-1151-2}, pages = {183 -- 195}, year = {2017}, abstract = {In mormyrid weakly electric fish, the electric organ discharge (EOD) is used for species recognition, orientation and prey localization. Produced in the muscle-derived adult electric organ, the EOD exhibits a wide diversity across species in both waveform and duration. While certain defining EOD characteristics can be linked to anatomical features of the electric organ, many factors underlying EOD differentiation are yet unknown. Here, we report the differential expression of 13 Kv1 voltage-gated potassium channel genes, two inwardly rectifying potassium channel genes, two previously studied sodium channel genes and an ATPase pump in two sympatric species of the genus Campylomormyrus in both the adult electric organ and skeletal muscle. Campylomormyrus compressirostris displays a basal EOD, largely unchanged during development, while C. tshokwe has an elongated, putatively derived discharge. We report an upregulation in all Kv1 genes in the electric organ of Campylomormyrus tshokwe when compared to both skeletal muscle and C. compressirostris electric organ. This pattern of upregulation in a species with a derived EOD form suggests that voltage-gated potassium channels are potentially involved in the diversification of the EOD signal among mormyrid weakly electric fish.}, language = {en} } @article{FeulnerKirschbaumTiedemann2005, author = {Feulner, Philine g. d. and Kirschbaum, Frank and Tiedemann, Ralph}, title = {Eighteen microsatellite loci for endemic African weakly electric fish (Campylomormyrus, Mormyridae) and their cross species applicability among related taxa}, year = {2005}, abstract = {We describe isolation and characterization of the first microsatellite loci specifically developed for African weakly electric fish (Mormyridae), for the genus Campylomormyrus. Seventeen of our 18 loci are polymorphic within the Campylomormyrus numenius species complex. The polymorphic loci showed four to 15 alleles per locus, an expected heterozygosity between 0.46 and 0.94, and an observed heterozygosity between 0.31 and 1.00. Most primers also yield reproducible results in several other mormyrid species. These loci comprise a set of molecular markers for various applications, from moderately polymorphic loci suitable for population studies to highly polymorphic loci for pedigree analysis in mormyrids}, language = {en} } @article{StuckasTiedemann2006, author = {Stuckas, H and Tiedemann, Ralph}, title = {Eight new microsatellite loci for the critically endangered fire-bellied toad Bombina bombina and their cross- species applicability among anurans}, doi = {10.1111/j.1471-8286.2005.01171.x}, year = {2006}, abstract = {We describe eight new microsatellite loci for the critically endangered fire-bellied toad, Bombina bombina. Seven of them are polymorphic with two to seven alleles per locus, an expected heterozygosity between 0.41 and 0.8, and an observed heterozygosity between 0.27 and 0.7. The yield of new loci was relatively low, presumably due to mildly repetitive sequence motifs in microsatellite flanking regions. As typical for anurans, cross-species amplification was limited (here, to congeners Bombina orientalis and Bombina variegata). Combining these new loci with those already available provides a reasonable number of loci for population studies and pedigree analysis in Bombina}, language = {en} } @article{PadurWedekindOeztuerketal.2009, author = {Padur, Lisa and Wedekind, Juliane and {\"O}zt{\"u}rk, {\"O}znur and Streit, Bruno and Tiedemann, Ralph and Plath, Martin}, title = {Do audience effects lead to relaxed male sexual harassment?}, issn = {0005-7959}, doi = {10.1163/000579509x12483520922124}, year = {2009}, abstract = {Several recent studies reported on so-called audience effects in male Atlantic mollies (Poecilia mexicana), in which the visual presence of a potential rival affects male sexual activity. We asked whether and how audience effects interact with male sexual harassment. Poecilia mexicana almost constantly attempt to mate, while females are mostly non- responsive to male approaches. Females flee from this sexual harassment and, thus, are more vigilant in the presence of males, so females may have hampered feeding opportunities. Do audience effects lead to altered male sexual harassment? Focal females were given an opportunity to feed in the presence of a male or a female partner and the difference in feeding times was interpreted as an effect caused by male harassment. Tests were conducted without an audience (1), or an audience male was visually presented either directly inside the test tank (2), or further away (in an adjoining compartment (3)). We found that levels of pre-mating behaviour did not vary significantly among treatments, but males exhibited more copulation attempts (thrusting) in treatment (3), suggesting that males respond to increased risk of sperm competition with higher sperm expenditure. Females fed less (and started feeding later) when a harassing partner male was around, and this effect was not dependent on the audience treatment, but, overall, females spent more time feeding (and started feeding earlier) when an audience was presented. Hence, feeding time reductions appear to be independent of audience effects, but perceived 'safety in numbers' may lead to increased foraging in larger groups.}, language = {en} } @article{KiemelWeithoffTiedemann2022, author = {Kiemel, Katrin and Weithoff, Guntram and Tiedemann, Ralph}, title = {DNA metabarcoding reveals impact of local recruitment, dispersal, and hydroperiod on assembly of a zooplankton metacommunity}, series = {Molecular ecology}, volume = {32}, journal = {Molecular ecology}, number = {23}, publisher = {Wiley}, address = {Hoboken}, issn = {0962-1083}, doi = {10.1111/mec.16627}, pages = {20}, year = {2022}, abstract = {Understanding the environmental impact on the assembly of local communities in relation to their spatial and temporal connectivity is still a challenge in metacommunity ecology. This study aims to unravel underlying metacommunity processes and environmental factors that result in observed zooplankton communities. Unlike most metacommunity studies, we jointly examine active and dormant zooplankton communities using a DNA metabarcoding approach to overcome limitations of morphological species identification. We applied two-fragment (COI and 18S) metabarcoding to monitor communities of 24 kettle holes over a two-year period to unravel (i) spatial and temporal connectivity of the communities, (ii) environmental factors influencing local communities, and (iii) dominant underlying metacommunity processes in this system. We found a strong separation of zooplankton communities from kettle holes of different hydroperiods (degree of permanency) throughout the season, while the community composition within single kettle holes did not differ between years. Species richness was primarily dependent on pH and permanency, while species diversity (Shannon Index) was influenced by kettle hole location. Community composition was impacted by kettle hole size and surrounding field crops. Environmental processes dominated temporal and spatial processes. Sediment communities showed a different composition compared to water samples but did not differ between ephemeral and permanent kettle holes. Our results suggest that communities are mainly structured by environmental filtering based on pH, kettle hole size, surrounding field crops, and permanency. Environmental filtering based on specific conditions in individual kettle holes seems to be the dominant process in community assembly in the studied zooplankton metacommunity.}, language = {en} } @article{NahavandiKetmaierPlathetal.2013, author = {Nahavandi, Nahid and Ketmaier, Valerio and Plath, Martin and Tiedemann, Ralph}, title = {Diversification of Ponto-Caspian aquatic fauna - morphology and molecules retrieve congruent evolutionary relationships in Pontogammarus maeoticus (Amphipoda: Pontogammaridae)}, series = {Molecular phylogenetics and evolution}, volume = {69}, journal = {Molecular phylogenetics and evolution}, number = {3}, publisher = {Elsevier}, address = {San Diego}, issn = {1055-7903}, doi = {10.1016/j.ympev.2013.05.021}, pages = {1063 -- 1076}, year = {2013}, abstract = {The geological history of the Ponto-Caspian region, with alternating cycles of isolation and reconnection among the three main basins (Black and Azov Seas, and the more distant Caspian Sea) as well as between them and the Mediterranean Sea, profoundly affected the diversification of its aquatic fauna, leading to a high degree of endemism. Two alternative hypotheses on the origin of this amazing biodiversity have been proposed, corresponding to phases of allopatric separation of aquatic fauna among sea basins: a Late Miocene origin (10-6 MYA) vs. a more recent Pleistocene ancestry (<2 MYA). Both hypotheses support a vicariant origin of (1) Black + Azov Sea lineages on the one hand, and (2) Caspian Sea lineages on the other. Here, we present a study on the Ponto-Caspian endemic amphipod Pontogammarus maeoticus. We assessed patterns of divergence based on (a) two mitochondrial and one nuclear gene, and (b) a morphometric analysis of 23 morphological traits in 16 populations from South and West Caspian Sea, South Azov Sea and North-West Black Sea. Genetic data indicate a long and independent evolutionary history, dating back from the late Miocene to early Pleistocene (6.6-1.6 MYA), for an unexpected, major split between (i) a Black Sea clade and (ii) a well-supported clade grouping individuals from the Caspian and Azov Seas. Absence of shared haplotypes argues against either recent or human-mediated exchanges between Caspian and Azov Seas. A mismatch distribution analysis supports more stable population demography in the Caspian than in the Black Sea populations. Morphological divergence largely followed patterns of genetic divergence: our analyses grouped samples according to the basin of origin and corroborated the close phylogenetic affinity between Caspian and Azov Sea lineages. Altogether, our results highlight the necessity of careful (group-specific) evaluation of evolutionary trajectories in marine taxa that should certainly not be inferred from the current geographical proximity of sea basins alone. (C) 2013 Elsevier Inc. All rights reserved.}, language = {en} } @article{ParaskevopoulouTiedemannWeithoff2018, author = {Paraskevopoulou, Sofia and Tiedemann, Ralph and Weithoff, Guntram}, title = {Differential response to heat stress among evolutionary lineages of an aquatic invertebrate species complex}, series = {Biology letters}, volume = {14}, journal = {Biology letters}, number = {11}, publisher = {Royal Society}, address = {London}, issn = {1744-9561}, doi = {10.1098/rsbl.2018.0498}, pages = {5}, year = {2018}, abstract = {Under global warming scenarios, rising temperatures can constitute heat stress to which species may respond differentially. Within a described species, knowledge on cryptic diversity is of further relevance, as different lineages/cryptic species may respond differentially to environmental change. The Brachionus calyciflorus species complex (Rotifera), which was recently described using integrative taxonomy, is an essential component of aquatic ecosystems. Here, we tested the hypothesis that these (formerly cryptic) species differ in their heat tolerance. We assigned 47 clones with nuclear ITS1 (nuITS1) and mitochondrial COI (mtCOI) markers to evolutionary lineages, now named B. calyciflorus sensu stricto (s.s.) and B. fernandoi. We selected 15 representative clones and assessed their heat tolerance as a bi-dimensional phenotypic trait affected by both the intensity and duration of heat stress. We found two distinct groups, with B. calyciflorus s.s. clones having higher heat tolerance than the novel species B. fernandoi. This apparent temperature specialization among former cryptic species underscores the necessity of a sound species delimitation and assignment, when organismal responses to environmental changes are investigated.}, language = {en} } @article{StuckasMesserschmidtPutzleretal.2009, author = {Stuckas, Heiko and Messerschmidt, Katrin and Putzler, Sascha and Baumann, Otto and Schenk, J{\"o}rg A. and Tiedemann, Ralph and Micheel, Burkhard}, title = {Detection and characterization of gamete-specific molecules in Mytilus edulis using selective antibody production}, issn = {1040-452X}, doi = {10.1002/Mrd.20916}, year = {2009}, abstract = {The mussel Mytilus edulis can be used as model to study the molecular basis of reproductive isolation because this species maintains its species integrity, despite of hybridizing in zones of contact with the closely related species M. trossulus or M. galloprovincialis. This study uses selective antibody production by means of hybridoma technology to identify molecules which are involved in sperm function of M. edulis. Fragmented sperm were injected into mice and 25 hybridoma cell clones were established to obtain monoclonal antibodies (mAb). Five clones were identified producing mAb targeting molecules putatively involved in sperm function based on enzyme immunoassays, dot and Western blotting as well as immunostaining of tissue sections. Specific localization of these mAb targets on sperm and partly also in somatic tissue suggests that all five antibodies bind to different molecules. The targets of the mAb obtained from clone G26-AG8 were identified using mass spectrometry (nano-LC-ESI-MS/MS) as M6 and M7 lysin. These acrosomal proteins have egg vitelline lyses function and are highly similar (76\%) which explains the cross reactivity of mAb G26- AG8. Furthermore, M7 lysin was recently shown to be under strong positive selection suggesting a role in interspecific reproductive isolation. This study shows that M6 and M7 lysin are not only found in the sperm acrosome but also in male somatic tissue of the mantle and the posterior adductor muscle, while being completely absent in females. The monoclonal antibody G26-AG8 described here will allow elucidating M7/M6 lysin function in somatic and gonad tissue of adult and developing animals.}, language = {en} } @article{LamannaKirschbaumTiedemann2014, author = {Lamanna, Francesco and Kirschbaum, Frank and Tiedemann, Ralph}, title = {De novo assembly and characterization of the skeletal muscle and electric organ transcriptomes of the African weakly electric fish Campylomormyrus compressirostris (Mormyridae, Teleostei)}, series = {Molecular ecology resources}, volume = {14}, journal = {Molecular ecology resources}, number = {6}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1755-098X}, doi = {10.1111/1755-0998.12260}, pages = {1222 -- 1230}, year = {2014}, abstract = {African weakly electric fishes (Mormyridae) underwent an outstanding adaptive radiation (about 200 species), putatively owing to their ability to communicate through species-specific weak electric signals. The electric organ discharge (EOD) is produced by muscle-derived electrocytes organized in piles to form an electric organ. Despite the importance of this trait as a prezygotic isolation mechanism, genomic resources remained limited. We present here a first draft of the skeletal muscle and electric organ transcriptomes from the weakly electric fish species Campylomormyrus compressirostris, obtained using the Illumina HiSeq2000 sequencing technology. Approximately 6.8 Gbp of cDNA sequence data were produced from both tissues, resulting in 57268109 raw reads for the skeletal muscle and 46934923 for the electric organ, and assembled de novo into 46143 and 89270 contigs, respectively. About 50\% of both transcriptomes were annotated after protein databases search. The two transcriptomes show similar profiles in terms of Gene Ontology categories composition. We identified several candidate genes which are likely to play a central role in the production and evolution of the electric signal. For most of these genes, and for many other housekeeping genes, we were able to obtain the complete or partial coding DNA sequences (CDS), which can be used for the development of primers to be utilized in qRT-PCR experiments. We present also the complete mitochondrial genome and compare it to those available from other weakly electric fish species. Additionally, we located 1671 SSR-containing regions with their flanking sites and designed the relative primers. This study establishes a first step in the development of genomic tools aimed at understanding the role of electric communication during speciation.}, language = {en} } @article{LamannaKirschbaumWauricketal.2015, author = {Lamanna, Francesco and Kirschbaum, Frank and Waurick, Isabelle and Dieterich, Christoph and Tiedemann, Ralph}, title = {Cross-tissue and cross-species analysis of gene expression in skeletal muscle and electric organ of African weakly-electric fish (Teleostei; Mormyridae)}, series = {BMC genomics}, volume = {16}, journal = {BMC genomics}, publisher = {BioMed Central}, address = {London}, issn = {1471-2164}, doi = {10.1186/s12864-015-1858-9}, pages = {17}, year = {2015}, abstract = {Background: African weakly-electric fishes of the family Mormyridae are able to produce and perceive weak electric signals (typically less than one volt in amplitude) owing to the presence of a specialized, muscle-derived electric organ (EO) in their tail region. Such electric signals, also known as Electric Organ Discharges (EODs), are used for objects/prey localization, for the identification of conspecifics, and in social and reproductive behaviour. This feature might have promoted the adaptive radiation of this family by acting as an effective pre-zygotic isolation mechanism. Despite the physiological and evolutionary importance of this trait, the investigation of the genetic basis of its function and modification has so far remained limited. In this study, we aim at: i) identifying constitutive differences in terms of gene expression between electric organ and skeletal muscle (SM) in two mormyrid species of the genus Campylomormyrus: C. compressirostris and C. tshokwe, and ii) exploring cross-specific patterns of gene expression within the two tissues among C. compressirostris, C. tshokwe, and the outgroup species Gnathonemus petersii. Results: Twelve paired-end (100 bp) strand-specific RNA-seq Illumina libraries were sequenced, producing circa 330 M quality-filtered short read pairs. The obtained reads were assembled de novo into four reference transcriptomes. In silico cross-tissue DE-analysis allowed us to identify 271 shared differentially expressed genes between EO and SM in C. compressirostris and C. tshokwe. Many of these genes correspond to myogenic factors, ion channels and pumps, and genes involved in several metabolic pathways. Cross-species analysis has revealed that the electric organ transcriptome is more variable in terms of gene expression levels across species than the skeletal muscle transcriptome. Conclusions: The data obtained indicate that: i) the loss of contractile activity and the decoupling of the excitation-contraction processes are reflected by the down-regulation of the corresponding genes in the electric organ's transcriptome; ii) the metabolic activity of the EO might be specialized towards the production and turn-over of membrane structures; iii) several ion channels are highly expressed in the EO in order to increase excitability; iv) several myogenic factors might be down-regulated by transcription repressors in the EO.}, language = {en} } @article{LamannaKirschbaumWauricketal.2015, author = {Lamanna, Francesco and Kirschbaum, Frank and Waurick, Isabelle and Dieterich, Christoph and Tiedemann, Ralph}, title = {Cross-tissue and cross-species analysis of gene expression in skeletal muscle and electric organ of African weakly-electric fish (Teleostei; Mormyridae)}, series = {BMC Genomics}, volume = {16}, journal = {BMC Genomics}, number = {668}, publisher = {Biomed Central}, address = {London}, issn = {1471-2164}, doi = {10.1186/s12864-015-1858-9}, year = {2015}, abstract = {Background African weakly-electric fishes of the family Mormyridae are able to produce and perceive weak electric signals (typically less than one volt in amplitude) owing to the presence of a specialized, muscle-derived electric organ (EO) in their tail region. Such electric signals, also known as Electric Organ Discharges (EODs), are used for objects/prey localization, for the identification of conspecifics, and in social and reproductive behaviour. This feature might have promoted the adaptive radiation of this family by acting as an effective pre-zygotic isolation mechanism. Despite the physiological and evolutionary importance of this trait, the investigation of the genetic basis of its function and modification has so far remained limited. In this study, we aim at: i) identifying constitutive differences in terms of gene expression between electric organ and skeletal muscle (SM) in two mormyrid species of the genus Campylomormyrus: C. compressirostris and C. tshokwe, and ii) exploring cross-specific patterns of gene expression within the two tissues among C. compressirostris, C. tshokwe, and the outgroup species Gnathonemus petersii. Results Twelve paired-end (100 bp) strand-specific RNA-seq Illumina libraries were sequenced, producing circa 330 M quality-filtered short read pairs. The obtained reads were assembled de novo into four reference transcriptomes. In silico cross-tissue DE-analysis allowed us to identify 271 shared differentially expressed genes between EO and SM in C. compressirostris and C.tshokwe. Many of these genes correspond to myogenic factors, ion channels and pumps, and genes involved in several metabolic pathways. Cross-species analysis has revealed that the electric organ transcriptome is more variable in terms of gene expression levels across species than the skeletal muscle transcriptome. Conclusions The data obtained indicate that: i) the loss of contractile activity and the decoupling of the excitation-contraction processes are reflected by the down-regulation of the corresponding genes in the electric organ's transcriptome; ii) the metabolic activity of the EO might be specialized towards the production and turn-over of membrane structures; iii) several ion channels are highly expressed in the EO in order to increase excitability; iv) several myogenic factors might be down-regulated by transcription repressors in the EO.}, language = {en} } @article{WronskiTiedemannApioetal.2006, author = {Wronski, Torsten and Tiedemann, Ralph and Apio, Ann and Plath, Martin}, title = {Cover, food, competitors and individual densities within bushbuck Tragelaphus scriptus female clan home ranges}, year = {2006}, abstract = {We examined factors predicting female densities within the common home ranges of related females ("clans") in bushbuck Tragelaphus scriptus Pallas, 1776. In this species, each female forms an individual home range, but the home ranges of matrilineal clan members strongly overlap. We found female densities to increase in areas with high canopy cover. Moreover, individual home range sizes tended to decrease with increasing cover. Food plant availability and intruder pressure by two heterospecific competitors did not significantly affect female densities. Apparently, canopy cover is the major limited resource in this species. A possible explanation is that both adult bushbuck and - even more markedly - fawns hide from predators in dense vegetation, in particular in thicket clumps and coalescences. The study shows an effect of habitat properties (eg sufficient canopy cover) on a within-population level in bushbuck, where female densities differ even among proximate clan areas}, language = {en} } @article{KorniienkoNguyenBaumgartneretal.2021, author = {Korniienko, Yevheniia and Nguyen, Linh and Baumgartner, Stephanie and Vater, Marianne and Tiedemann, Ralph and Kirschbaum, Frank}, title = {Correction to: Intragenus F1-hybrids of African weakly electric fish (Mormyridae: Campylomormyrus tamandua male x C. compressirostris female) are fertile (vol 206, pg 571, 2020)}, series = {Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology}, volume = {207}, journal = {Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology}, number = {6}, publisher = {Springer}, address = {Heidelberg}, issn = {0340-7594}, doi = {10.1007/s00359-021-01513-2}, pages = {773 -- 773}, year = {2021}, language = {en} } @article{PaulMamonekeneVateretal.2015, author = {Paul, Christiane and Mamonekene, Victor and Vater, Marianne and Feulner, Philine G. D. and Engelmann, Jacob and Tiedemann, Ralph and Kirschbaum, Frank}, title = {Comparative histology of the adult electric organ among four species of the genus Campylomormyrus (Teleostei: Mormyridae)}, series = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, volume = {201}, journal = {Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology}, number = {4}, publisher = {Springer}, address = {New York}, issn = {0340-7594}, doi = {10.1007/s00359-015-0995-6}, pages = {357 -- 374}, year = {2015}, abstract = {The electric organ (EO) of weakly electric mormyrids consists of flat, disk-shaped electrocytes with distinct anterior and posterior faces. There are multiple species-characteristic patterns in the geometry of the electrocytes and their innervation. To further correlate electric organ discharge (EOD) with EO anatomy, we examined four species of the mormyrid genus Campylomormyrus possessing clearly distinct EODs. In C. compressirostris, C. numenius, and C. tshokwe, all of which display biphasic EODs, the posterior face of the electrocytes forms evaginations merging to a stalk system receiving the innervation. In C. tamandua that emits a triphasic EOD, the small stalks of the electrocyte penetrate the electrocyte anteriorly before merging on the anterior side to receive the innervation. Additional differences in electrocyte anatomy among the former three species with the same EO geometry could be associated with further characteristics of their EODs. Furthermore, in C. numenius, ontogenetic changes in EO anatomy correlate with profound changes in the EOD. In the juvenile the anterior face of the electrocyte is smooth, whereas in the adult it exhibits pronounced surface foldings. This anatomical difference, together with disparities in the degree of stalk furcation, probably contributes to the about 12 times longer EOD in the adult.}, language = {en} } @article{ParrySchlaegelTiedemannetal.2022, author = {Parry, Victor and Schl{\"a}gel, Ulrike E. and Tiedemann, Ralph and Weithoff, Guntram}, title = {Behavioural Responses of Defended and Undefended Prey to Their Predator}, series = {Biology}, volume = {11}, journal = {Biology}, number = {8}, publisher = {MDPI}, address = {Basel, Schweiz}, issn = {2079-7737}, doi = {10.3390/biology11081217}, pages = {14}, year = {2022}, abstract = {Predation is a strong species interaction causing severe harm or death to prey. Thus, prey species have evolved various defence strategies to minimize predation risk, which may be immediate (e.g., a change in behaviour) or transgenerational (morphological defence structures). We studied the behaviour of two strains of a rotiferan prey (Brachionus calyciflorus) that differ in their ability to develop morphological defences in response to their predator Asplanchna brightwellii. Using video analysis, we tested: (a) if two strains differ in their response to predator presence and predator cues when both are undefended; (b) whether defended individuals respond to live predators or their cues; and (c) if the morphological defence (large spines) per se has an effect on the swimming behaviour. We found a clear increase in swimming speed for both undefended strains in predator presence. However, the defended specimens responded neither to the predator presence nor to their cues, showing that they behave indifferently to their predator when they are defended. We did not detect an effect of the spines on the swimming behaviour. Our study demonstrates a complex plastic behaviour of the prey, not only in the presence of their predator, but also with respect to their defence status.}, language = {en} } @article{ParrySchlaegelTiedemannetal.2022, author = {Parry, Victor and Schl{\"a}gel, Ulrike E. and Tiedemann, Ralph and Weithoff, Guntram}, title = {Behavioural responses of defended and undefended prey to their predator}, series = {Biology : open access journal}, volume = {11}, journal = {Biology : open access journal}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2079-7737}, doi = {10.3390/biology11081217}, pages = {14}, year = {2022}, abstract = {Many animals that have to cope with predation have evolved mechanisms to reduce their predation risk. One of these mechanisms is change in morphology, for example, the development of spines. These spines are induced, when mothers receive chemical signals of a predator (kairomones) and their daughters are then equipped with defensive spines. We studied the behaviour of a prey and its predator when the prey is either defended or undefended. We used common aquatic micro-invertebrates, the rotifers Brachionus calyciflorus (prey) and Asplanchna brightwellii (predator) as experimental animals. We found that undefended prey increased its swimming speed in the presence of the predator. The striking result was that the defended prey did not respond to the predator's presence. This suggests that defended prey has a different response behaviour to a predator than undefended conspecifics. Our study provides further insights into complex zooplankton predator-prey interactions. Predation is a strong species interaction causing severe harm or death to prey. Thus, prey species have evolved various defence strategies to minimize predation risk, which may be immediate (e.g., a change in behaviour) or transgenerational (morphological defence structures). We studied the behaviour of two strains of a rotiferan prey (Brachionus calyciflorus) that differ in their ability to develop morphological defences in response to their predator Asplanchna brightwellii. Using video analysis, we tested: (a) if two strains differ in their response to predator presence and predator cues when both are undefended; (b) whether defended individuals respond to live predators or their cues; and (c) if the morphological defence (large spines) per se has an effect on the swimming behaviour. We found a clear increase in swimming speed for both undefended strains in predator presence. However, the defended specimens responded neither to the predator presence nor to their cues, showing that they behave indifferently to their predator when they are defended. We did not detect an effect of the spines on the swimming behaviour. Our study demonstrates a complex plastic behaviour of the prey, not only in the presence of their predator, but also with respect to their defence status.}, language = {en} }