TY - JOUR A1 - Gross, Stephanie A1 - Claus, Philip A1 - Wohlsein, Peter A1 - Kesselring, Tina A1 - Lakemeyer, Jan A1 - Reckendorf, Anja A1 - Roller, Marco A1 - Tiedemann, Ralph A1 - Siebert, Ursula T1 - Indication of lethal interactions between a solitary bottlenose dolphin (Tursiops truncatus) and harbor porpoises (Phocoena phocoena) in the German Baltic Sea JF - BMC zoology N2 - 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. KW - Cetaceans KW - Interspecific aggression KW - Porpicide KW - Blunt trauma KW - Mortality KW - Stranding Y1 - 2020 U6 - https://doi.org/10.1186/s40850-020-00061-7 SN - 2056-3132 VL - 5 IS - 1 PB - BMC CY - London ER - TY - JOUR A1 - Marrone, F. A1 - Havenstein, Katja A1 - Tiedemann, Ralph A1 - Ketmaier, V. T1 - Identification and characterization of five polymorphic microsatellite loci in the freshwater copepod Hemidiaptomus gurneyi (Copepoda: Calanoida: Diaptomidae) JF - The Italian journal of zoology N2 - 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. KW - Mediterranean temporary ponds KW - diaptomid copepods KW - SSRs Y1 - 2016 U6 - https://doi.org/10.1080/11250003.2015.1126363 SN - 1125-0003 SN - 1748-5851 VL - 83 SP - 146 EP - 150 PB - Springer CY - Abingdon ER - TY - JOUR A1 - Trauth, Martin H. A1 - Maslin, Mark A. A1 - Deino, Alan L. A1 - Junginger, Annett A1 - Lesoloyia, Moses A1 - Odada, Eric O. A1 - Olago, Daniel O. A1 - Olaka, Lydia A. A1 - Strecker, Manfred A1 - Tiedemann, Ralph T1 - Human evolution in a variable environment : the amplifier lakes of Eastern Africa N2 - 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. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/02773791 U6 - https://doi.org/10.1016/j.quascirev.2010.07.007 SN - 0277-3791 ER - TY - JOUR A1 - Epp, Laura Saskia A1 - Stoof, Kathleen R. A1 - Trauth, Martin H. A1 - Tiedemann, Ralph T1 - Historical genetics on a sediment core from a Kenyan lake : intraspecific genotype turnover in a tropical rotifer is related to past environmental changes N2 - 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. Y1 - 2010 UR - http://www.springerlink.com/content/100294 U6 - https://doi.org/10.1007/s10933-009-9379-7 SN - 0921-2728 ER - TY - JOUR A1 - Autenrieth, Marijke A1 - Hartmann, Stefanie A1 - Lah, Ljerka A1 - Roos, Anna A1 - Dennis, Alice B. A1 - Tiedemann, Ralph T1 - High-quality whole-genome sequence of an abundant Holarctic odontocete, the harbour porpoise (Phocoena phocoena) JF - Molecular ecology resources N2 - 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. KW - cetaceans KW - genomics/proteomics KW - mammals KW - molecular evolution Y1 - 2018 U6 - https://doi.org/10.1111/1755-0998.12932 SN - 1755-098X SN - 1755-0998 VL - 18 IS - 6 SP - 1469 EP - 1481 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Epp, Laura Saskia A1 - Trauth, Martin H. A1 - Tiedemann, Ralph T1 - Hidden diversity in diatoms of Kenyan Lake Naivasha a genetic approach detects temporal variation JF - Molecular ecology N2 - 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. KW - diatoms KW - DNA barcoding KW - historical DNA KW - intra-specific variation KW - rbcL KW - tropical lake sediments Y1 - 2012 U6 - https://doi.org/10.1111/j.1365-294X.2011.05412.x SN - 0962-1083 VL - 21 IS - 8 SP - 1918 EP - 1930 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Cahsan, Binia De A1 - Westbury, Michael V. A1 - Paraskevopoulou, Sofia A1 - Drews, Hauke A1 - Ott, Moritz A1 - Gollmann, Günter A1 - Tiedemann, Ralph T1 - Genomic consequences of human-mediated translocations in margin populations of an endangered amphibian JF - Evolutionary Applications N2 - 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. KW - adaptive introgression KW - admixture KW - Bombina bombina KW - genetic rescue KW - mitogenomes KW - transcriptomics Y1 - 2020 U6 - https://doi.org/10.1111/eva.13229 SN - 1752-4563 VL - 14 IS - 6 PB - John Wiley & Sons, Inc. CY - New Jersey ER - TY - JOUR A1 - Sharma, Reeta A1 - Stuckas, Heiko A1 - Bhaskar, Ranjana A1 - Khan, Imran A1 - Goyal, Surendra Prakash A1 - Tiedemann, Ralph T1 - Genetically distinct population of Bengal tiger (Panthera tigris tigris) in Terai Arc Landscape (TAL) of India JF - Mammalian biology = Zeitschrift für Säugetierkunde N2 - 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. KW - Bengal tiger KW - Population genetics KW - mtDNA haplotype KW - Terai Arc Y1 - 2011 U6 - https://doi.org/10.1016/j.mambio.2010.10.005 SN - 1616-5047 VL - 76 IS - 4 SP - 484 EP - 490 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Dominguez, Marisol A1 - Tiedemann, Ralph A1 - Reboreda, Juan C. A1 - Segura, Luciano A1 - Tittarelli, Fabian A1 - Mahler, Bettina T1 - Genetic structure reveals management units for the yellow cardinal (Gubernatrix cristata), endangered by habitat loss and illegal trapping JF - Conservation genetics KW - Genetic structure KW - Gubernatrix cristata KW - Management units KW - MtDNA KW - Microsatellites KW - Hybrids Y1 - 2017 U6 - https://doi.org/10.1007/s10592-017-0964-4 SN - 1566-0621 SN - 1572-9737 VL - 18 SP - 1131 EP - 1140 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Dolgener, Nicola A1 - Schröder, Christiane A1 - Schneeweiss, N. A1 - Tiedemann, Ralph T1 - Genetic population structure of the Fire-bellied toad Bombina bombina in an area of high population density implications for conservation JF - Hydrobiologia : acta hydrobiologica, hydrographica, limnologica et protistologica N2 - 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. KW - Conservation genetics KW - Fire-bellied toad KW - Fragmentation KW - Mitochondrial DNA KW - Microsatellites KW - Translocation Y1 - 2012 U6 - https://doi.org/10.1007/s10750-012-1016-1 SN - 0018-8158 VL - 689 IS - 1 SP - 111 EP - 120 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Herzschuh, Ulrike A1 - Pestryakova, Luidmila Agafyevna A1 - Klemm, Juliane A1 - Epp, Laura Saskia A1 - Tiedemann, Ralph T1 - Genetic data from algae sedimentary DNA reflect the influence of environment over geography JF - Scientific reports N2 - 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. Y1 - 2015 U6 - https://doi.org/10.1038/srep12924 SN - 2045-2322 VL - 5 PB - Nature Publ. Group CY - London ER - TY - JOUR A1 - Pavesi, Laura A1 - Tiedemann, Ralph A1 - DeMatthaeis, Elvira A1 - Ketmaier, Valerio T1 - Genetic connectivity between land and sea: the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea Y1 - 2013 UR - 1960 = DOI: 10.1186/1742-9994-10-21 SN - 1742-9994 ER - TY - JOUR A1 - Pavesi, Laura A1 - Tiedemann, Ralph A1 - De Matthaeis, Elvira A1 - Ketmaier, Valerio T1 - Genetic connectivity between land and sea - the case of the beachflea Orchestia montagui (Crustacea, Amphipoda, Talitridae) in the Mediterranean Sea JF - Frontiers in zoology N2 - 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. KW - Orchestia montagui KW - Talitrids KW - Mediterranean Sea KW - Phylogeography KW - Mitochondrial DNA KW - Microsatellites KW - Allozymes KW - Approximate Bayesian Computation Y1 - 2013 U6 - https://doi.org/10.1186/1742-9994-10-21 SN - 1742-9994 VL - 10 IS - 4-5 PB - BioMed Central CY - London ER - TY - JOUR A1 - Milinkovitch, M. C. A1 - Monteyne, D. A1 - Gibbs, J. P. A1 - Fritts, T. H. A1 - Tapia, W. A1 - Snell, H. L. A1 - Tiedemann, Ralph A1 - Caccone, Adalgisa A1 - Powell, J. R. T1 - Genetic analysis of a successful repatriation programme : giant Galapagos tortoises N2 - 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 Y1 - 2004 SN - 0962-8452 ER - TY - JOUR A1 - Sammler, Svenja A1 - Bleidorn, Christoph A1 - Tiedemann, Ralph T1 - Full mitochondrial genome sequences of two endemic Philippine hornbill species (Aves: Bucerotidae) provide evidence for pervasive mitochondrial DNA recombination JF - BMC genomics N2 - 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. Y1 - 2011 U6 - https://doi.org/10.1186/1471-2164-12-35 SN - 1471-2164 VL - 12 IS - 2 PB - BioMed Central CY - London ER - TY - JOUR A1 - Sammler, Svenja A1 - Havenstein, Katja A1 - Tiedemann, Ralph T1 - Fourteen new microsatellite markers for the Visayan tarictic hornbill (Penelopides panini) and their cross-species applicability among other endangered Philippine hornbills JF - Conservation genetics resources N2 - 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. KW - Aceros KW - Bucerotidae KW - Cross-species amplification KW - Microsatellites KW - Penelopides Philippine hornbills Y1 - 2012 U6 - https://doi.org/10.1007/s12686-011-9567-4 SN - 1877-7252 VL - 4 IS - 2 SP - 435 EP - 438 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Reckendorf, Anja A1 - Ludes-Wehrmeister, Eva A1 - Wohlsein, Peter A1 - Tiedemann, Ralph A1 - Siebert, U. A1 - Lehnert, Kristina T1 - First record of Halocercus sp (Pseudaliidae) lungworm infections in two stranded neonatal orcas (Orcinus orca) JF - Parasitology N2 - 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. KW - Cetaceans KW - endoparasites KW - killer whale KW - life cycle KW - nematodes KW - vertical transmission Y1 - 2018 U6 - https://doi.org/10.1017/S0031182018000586 SN - 0031-1820 SN - 1469-8161 VL - 145 IS - 12 SP - 1553 EP - 1557 PB - Cambridge Univ. Press CY - New York ER - TY - JOUR A1 - Apio, Ann A1 - Kabasa, John David A1 - Ketmaier, Valerio A1 - Schroeder, Christoph A1 - Plath, Martin A1 - Tiedemann, Ralph T1 - Female philopatry and male dispersal in a cryptic, bush-dwelling antelope : a combined molecular and behavioural approach N2 - 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. Y1 - 2010 UR - http://www3.interscience.wiley.com/cgi-bin/issn?DESCRIPTOR=PRINTISSN&VALUE=0952-8369 U6 - https://doi.org/10.1111/j.1469-7998.2009.00654.x SN - 0952-8369 ER - TY - JOUR A1 - Krüger, Johanna A1 - Foerster, Verena Elisabeth A1 - Trauth, Martin H. A1 - Hofreiter, Michael A1 - Tiedemann, Ralph T1 - Exploring the Past Biosphere of Chew Bahir/Southern Ethiopia: Cross-Species Hybridization Capture of Ancient Sedimentary DNA from a Deep Drill Core JF - Frontiers in Earth Science N2 - 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. KW - Chew Bahir KW - hybridization capture KW - ICDP KW - paleoclimate KW - past biosphere KW - sedaDNA KW - sediment core Y1 - 2021 U6 - https://doi.org/10.3389/feart.2021.683010 SN - 2296-6463 SP - 1 EP - 20 PB - Frontiers in Earth Science CY - Lausanne, Schweiz ER - TY - JOUR A1 - Hartmann, Stefanie A1 - Helm, Conrad A1 - Nickel, Birgit A1 - Meyer, Matthias A1 - Struck, Torsten H. A1 - Tiedemann, Ralph A1 - Selbig, Joachim A1 - Bleidorn, Christoph T1 - Exploiting gene families for phylogenomic analysis of myzostomid transcriptome data JF - PLoS one N2 - 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. Y1 - 2012 U6 - https://doi.org/10.1371/journal.pone.0029843 SN - 1932-6203 VL - 7 IS - 1 PB - PLoS CY - San Fransisco ER - TY - JOUR A1 - Stuckas, Heiko A1 - Stoof, Kathleen A1 - Quesada, Humberto A1 - Tiedemann, Ralph T1 - Evolutionary implications of discordant clines across the Baltic Mytilus hybrid zone (Mytilus edulis and Mytilus trossulus) N2 - 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. Y1 - 2009 UR - http://www.nature.com/hdy/archive/index.html U6 - https://doi.org/10.1038/Hdy.2009.37 SN - 0018-067X ER - TY - JOUR A1 - Paul, Christiane A1 - Kirschbaum, Frank A1 - Mamonekene, Victor A1 - Tiedemann, Ralph T1 - Evidence for Non-neutral Evolution in a Sodium Channel Gene in African Weakly Electric Fish (Campylomormyrus, Mormyridae) JF - Journal of molecular evolution N2 - 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. KW - Mormyridae KW - Mormyroidea KW - Campylomormyrus KW - SCN4aa KW - Voltage-gated sodium channel KW - Positive selection Y1 - 2016 U6 - https://doi.org/10.1007/s00239-016-9754-8 SN - 0022-2844 SN - 1432-1432 VL - 83 SP - 61 EP - 77 PB - Springer CY - New York ER - TY - JOUR A1 - Valente, Luis A1 - Illera, Juan Carlos A1 - Havenstein, Katja A1 - Pallien, Tamara A1 - Etienne, Rampal S. A1 - Tiedemann, Ralph T1 - Equilibrium Bird Species Diversity in Atlantic Islands JF - Current biology Y1 - 2017 U6 - https://doi.org/10.1016/j.cub.2017.04.053 SN - 0960-9822 SN - 1879-0445 VL - 27 SP - 1660 EP - + PB - Cell Press CY - Cambridge ER - TY - JOUR A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Junginger, Annett A1 - Olaka, Lydia A. A1 - Tiedemann, Ralph A1 - Trauth, Martin H. T1 - Environmental variability in Lake Naivasha, Kenya, over the last two centuries JF - Journal of paleolimnolog N2 - 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. KW - Lake sediments KW - Diatoms KW - Conductivity KW - Lake Naivasha KW - Human impact KW - Eutrophication Y1 - 2011 U6 - https://doi.org/10.1007/s10933-011-9502-4 SN - 0921-2728 VL - 45 IS - 3 SP - 353 EP - 367 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Dolgener, N. A1 - Freudenberger, L. A1 - Schluck, M. A1 - Schneeweiss, N. A1 - Ibisch, P. L. A1 - Tiedemann, Ralph T1 - Environmental niche factor analysis (ENFA) relates environmental parameters to abundance and genetic diversity in an endangered amphibian, the fire-bellied-toad (Bombina bombina) JF - Conservation genetics N2 - 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. KW - Distribution modelling KW - ENFA KW - Genetic diversity KW - Fire-bellied toad KW - Landscape genetics KW - Road disturbance Y1 - 2014 U6 - https://doi.org/10.1007/s10592-013-0517-4 SN - 1566-0621 SN - 1572-9737 VL - 15 IS - 1 SP - 11 EP - 21 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Romero-Mujalli, Daniel A1 - Jeltsch, Florian A1 - Tiedemann, Ralph T1 - Elevated mutation rates are unlikely to evolve in sexual species, not even under rapid environmental change JF - BMC Evolutionary Biology N2 - 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. KW - Individual-based models KW - sexual species KW - Beneficial mutations KW - Recombination KW - Directional climate change KW - Mutator locus KW - Mutation rate Y1 - 2019 U6 - https://doi.org/10.1186/s12862-019-1494-0 SN - 1471-2148 VL - 19 PB - BioMed Central CY - London ER - TY - JOUR A1 - Feulner, Philine G. D. A1 - Kirschbaum, Frank A1 - Schugardt, Christian A1 - Ketmaier, Valerio A1 - Tiedemann, Ralph T1 - Electrophysiological and molecular genetic evidence for sympatrically occuring cryptic species in African weakly electric fishes (Teleostei : Mormyridae : Campylomormyrus) N2 - 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. Y1 - 2006 UR - http://www.sciencedirect.com/science/journal/10557903 U6 - https://doi.org/10.1016/j.ympev.2005.09.008 SN - 1055-7903 ER - TY - JOUR A1 - Feulner, Philine G. D. A1 - Plath, Martin A1 - Engelmann, Jacob A1 - Kirschbaum, Frank A1 - Tiedemann, Ralph T1 - Electrifying love : electric fish use species-specific discharge for mate recognition N2 - 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. Y1 - 2009 UR - http://www.journals.royalsoc.ac.uk/link.asp?id=110824 U6 - https://doi.org/10.1098/rsbl.2008.0566 SN - 1744-9561 ER - TY - JOUR A1 - Nagel, Rebecca A1 - Kirschbaum, Frank A1 - Hofmann, Volker A1 - Engelmann, Jacob A1 - Tiedemann, Ralph T1 - Electric pulse characteristics can enable species recognition in African weakly electric fish species JF - Scientific Reports N2 - 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. KW - Dwelling Atlantic Mollies KW - Organ Discharge Patterns KW - Mormyrid Fish KW - Pollimyrus-Isidori KW - Acoustic-Signals KW - Sexual Selection KW - Phylogenetic-Relationships KW - Hypopomus-Occidentalis KW - Convergent Evolution KW - Poecili-Mexicana Y1 - 2018 U6 - https://doi.org/10.1038/s41598-018-29132-z SN - 2045-2322 VL - 8 SP - 1 EP - 12 PB - Nature Publishing Group CY - London ER - TY - JOUR A1 - Nagel, Rebecca A1 - Kirschbaum, Frank A1 - Tiedemann, Ralph T1 - Electric organ discharge diversification in mormyrid weakly electric fish is associated with differential expression of voltage-gated ion channel genes JF - Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology N2 - 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. KW - Weakly electric fish KW - Ion channels KW - Electric organ KW - Gene expression KW - Campylomormyrus Y1 - 2017 U6 - https://doi.org/10.1007/s00359-017-1151-2 SN - 0340-7594 SN - 1432-1351 VL - 203 SP - 183 EP - 195 PB - Springer CY - New York ER - TY - JOUR A1 - Feulner, Philine g. d. A1 - Kirschbaum, Frank A1 - Tiedemann, Ralph T1 - Eighteen microsatellite loci for endemic African weakly electric fish (Campylomormyrus, Mormyridae) and their cross species applicability among related taxa N2 - 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 Y1 - 2005 ER - TY - JOUR A1 - Stuckas, H A1 - Tiedemann, Ralph T1 - Eight new microsatellite loci for the critically endangered fire-bellied toad Bombina bombina and their cross- species applicability among anurans N2 - 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 Y1 - 2006 UR - http://onlinelibrary.wiley.com/doi/10.1111/j.1471-8286.2005.01171.x/pdf U6 - https://doi.org/10.1111/j.1471-8286.2005.01171.x ER - TY - JOUR A1 - Padur, Lisa A1 - Wedekind, Juliane A1 - Öztürk, Öznur A1 - Streit, Bruno A1 - Tiedemann, Ralph A1 - Plath, Martin T1 - Do audience effects lead to relaxed male sexual harassment? N2 - 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. Y1 - 2009 UR - http://brill.publisher.ingentaconnect.com/content/brill/beh U6 - https://doi.org/10.1163/000579509x12483520922124 SN - 0005-7959 ER - TY - JOUR A1 - Kiemel, Katrin A1 - Weithoff, Guntram A1 - Tiedemann, Ralph T1 - DNA metabarcoding reveals impact of local recruitment, dispersal, and hydroperiod on assembly of a zooplankton metacommunity JF - Molecular ecology N2 - 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. KW - bulk DNA KW - dispersal KW - DNA-metabarcoding KW - environmental filtering; KW - metacommunity KW - zooplankton Y1 - 2022 U6 - https://doi.org/10.1111/mec.16627 SN - 0962-1083 SN - 1365-294X VL - 32 IS - 23 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Nahavandi, Nahid A1 - Ketmaier, Valerio A1 - Plath, Martin A1 - Tiedemann, Ralph T1 - Diversification of Ponto-Caspian aquatic fauna - morphology and molecules retrieve congruent evolutionary relationships in Pontogammarus maeoticus (Amphipoda: Pontogammaridae) JF - Molecular phylogenetics and evolution N2 - 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. KW - Biodiversity hotspot KW - Black Sea KW - Caspian Sea KW - Paratethys KW - Sea of Azov KW - Vicariance Y1 - 2013 U6 - https://doi.org/10.1016/j.ympev.2013.05.021 SN - 1055-7903 SN - 1095-9513 VL - 69 IS - 3 SP - 1063 EP - 1076 PB - Elsevier CY - San Diego ER - TY - JOUR A1 - Paraskevopoulou, Sofia A1 - Tiedemann, Ralph A1 - Weithoff, Guntram T1 - Differential response to heat stress among evolutionary lineages of an aquatic invertebrate species complex JF - Biology letters N2 - 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. KW - Brachionus calyciflorus KW - critical thermal maximum KW - cryptic species KW - ecological speciation KW - rotifers KW - heat tolerance Y1 - 2018 U6 - https://doi.org/10.1098/rsbl.2018.0498 SN - 1744-9561 SN - 1744-957X VL - 14 IS - 11 PB - Royal Society CY - London ER - TY - JOUR A1 - Stuckas, Heiko A1 - Messerschmidt, Katrin A1 - Putzler, Sascha A1 - Baumann, Otto A1 - Schenk, Jörg A. A1 - Tiedemann, Ralph A1 - Micheel, Burkhard T1 - Detection and characterization of gamete-specific molecules in Mytilus edulis using selective antibody production N2 - 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. Y1 - 2009 UR - http://www3.interscience.wiley.com/cgi-bin/jhome/37692 U6 - https://doi.org/10.1002/Mrd.20916 SN - 1040-452X ER - TY - JOUR A1 - Lamanna, Francesco A1 - Kirschbaum, Frank A1 - Tiedemann, Ralph T1 - De novo assembly and characterization of the skeletal muscle and electric organ transcriptomes of the African weakly electric fish Campylomormyrus compressirostris (Mormyridae, Teleostei) JF - Molecular ecology resources N2 - 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. KW - cSSR KW - electric fish KW - electric organ KW - skeletal muscle KW - transcriptome Y1 - 2014 U6 - https://doi.org/10.1111/1755-0998.12260 SN - 1755-098X SN - 1755-0998 VL - 14 IS - 6 SP - 1222 EP - 1230 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Lamanna, Francesco A1 - Kirschbaum, Frank A1 - Waurick, Isabelle A1 - Dieterich, Christoph A1 - Tiedemann, Ralph T1 - Cross-tissue and cross-species analysis of gene expression in skeletal muscle and electric organ of African weakly-electric fish (Teleostei; Mormyridae) JF - BMC genomics N2 - 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. Y1 - 2015 U6 - https://doi.org/10.1186/s12864-015-1858-9 SN - 1471-2164 VL - 16 PB - BioMed Central CY - London ER - TY - JOUR A1 - Lamanna, Francesco A1 - Kirschbaum, Frank A1 - Waurick, Isabelle A1 - Dieterich, Christoph A1 - Tiedemann, Ralph T1 - Cross-tissue and cross-species analysis of gene expression in skeletal muscle and electric organ of African weakly-electric fish (Teleostei; Mormyridae) JF - BMC Genomics N2 - 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. Y1 - 2015 U6 - https://doi.org/10.1186/s12864-015-1858-9 SN - 1471-2164 VL - 16 IS - 668 PB - Biomed Central CY - London ER - TY - JOUR A1 - Wronski, Torsten A1 - Tiedemann, Ralph A1 - Apio, Ann A1 - Plath, Martin T1 - Cover, food, competitors and individual densities within bushbuck Tragelaphus scriptus female clan home ranges N2 - 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 Y1 - 2006 ER - TY - JOUR A1 - Korniienko, Yevheniia A1 - Nguyen, Linh A1 - Baumgartner, Stephanie A1 - Vater, Marianne A1 - Tiedemann, Ralph A1 - Kirschbaum, Frank T1 - 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) JF - Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology Y1 - 2021 U6 - https://doi.org/10.1007/s00359-021-01513-2 SN - 0340-7594 SN - 1432-1351 VL - 207 IS - 6 SP - 773 EP - 773 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Paul, Christiane A1 - Mamonekene, Victor A1 - Vater, Marianne A1 - Feulner, Philine G. D. A1 - Engelmann, Jacob A1 - Tiedemann, Ralph A1 - Kirschbaum, Frank T1 - Comparative histology of the adult electric organ among four species of the genus Campylomormyrus (Teleostei: Mormyridae) JF - Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology N2 - 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. KW - Mormyridae KW - Campylomormyrus KW - Electric organ discharge KW - Electrocyte geometry KW - Electric organ ontogeny Y1 - 2015 U6 - https://doi.org/10.1007/s00359-015-0995-6 SN - 0340-7594 SN - 1432-1351 VL - 201 IS - 4 SP - 357 EP - 374 PB - Springer CY - New York ER - TY - JOUR A1 - Parry, Victor A1 - Schlägel, Ulrike E. A1 - Tiedemann, Ralph A1 - Weithoff, Guntram T1 - Behavioural Responses of Defended and Undefended Prey to Their Predator BT - A Case Study of Rotifera JF - Biology N2 - 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. KW - animal behaviour KW - transgenerational response KW - Brachionus calyciflorus KW - Asplanchna brightwellii KW - video analysis Y1 - 2022 U6 - https://doi.org/10.3390/biology11081217 SN - 2079-7737 VL - 11 IS - 8 PB - MDPI CY - Basel, Schweiz ER - TY - JOUR A1 - Parry, Victor A1 - Schlägel, Ulrike E. A1 - Tiedemann, Ralph A1 - Weithoff, Guntram T1 - Behavioural responses of defended and undefended prey to their predator BT - a case study of rotifera JF - Biology : open access journal N2 - 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. KW - animal behaviour KW - transgenerational response KW - Brachionus calyciflorus KW - Asplanchna brightwellii KW - video analysis Y1 - 2022 U6 - https://doi.org/10.3390/biology11081217 SN - 2079-7737 VL - 11 IS - 8 PB - MDPI CY - Basel ER - TY - JOUR A1 - Plath, Martin A1 - Kromuszczynski, Katja A1 - Tiedemann, Ralph T1 - Audience effect alters male but not female mating preferences N2 - Males often face strong mating competition by neighboring males in their social environment. A recent study by Plath et al. (Anim Behav 75:21-29, 2008a) has demonstrated that the visual presence of a male competitor (i.e., an audience male) affects the expression of male mating preferences in a poeciliid fish (Poecilia mexicana) with a weaker expression of mating preferences when an audience male observed the focal male. This may be a tactic to reduce sperm competition, since surrounding males likely share intrinsic preferences for female traits or copy mate choice decisions. Here, we examined the hypothesis that a same-sex audience would affect female mate preferences less than male mating preferences. Our hypothesis was based on the assumptions that (1) competition for mates in a fashion that would be comparable in strength to sperm competition or overt male-male aggression is absent among Poecilia females, and (2) P. mexicana females typically form female-biased shoals, such that almost any female mate choice in nature occurs in front of a female audience. Poecilia females (P. mexicana, surface and cave form, and the closely related gynogenetic Poecilia formosa) were given a choice between a large and a small male, and the tests were repeated while a conspecific, a heterospecific, or no audience female (control) was presented. Females spent more time in the neutral zone and, thus, less time near the males during the second part of a trial when an audience was presented, but-consistent with predictions-females showed only slightly weaker expression of mate preferences during the second part of the tests. This decline was not specific to the treatment involving an audience and was significantly weaker than the effect seen in the male sex. Y1 - 2009 UR - http://www.springerlink.com/content/100464 U6 - https://doi.org/10.1007/s00265-008-0672-7 SN - 0340-5443 ER - TY - JOUR A1 - Hill, Natascha A1 - Leow, Alexander A1 - Bleidorn, Christoph A1 - Groth, Detlef A1 - Tiedemann, Ralph A1 - Selbig, Joachim A1 - Hartmann, Stefanie T1 - Analysis of phylogenetic signal in protostomial intron patterns using Mutual Information JF - Theory in biosciences N2 - Many deep evolutionary divergences still remain unresolved, such as those among major taxa of the Lophotrochozoa. As alternative phylogenetic markers, the intron-exon structure of eukaryotic genomes and the patterns of absence and presence of spliceosomal introns appear to be promising. However, given the potential homoplasy of intron presence, the phylogenetic analysis of this data using standard evolutionary approaches has remained a challenge. Here, we used Mutual Information (MI) to estimate the phylogeny of Protostomia using gene structure data, and we compared these results with those obtained with Dollo Parsimony. Using full genome sequences from nine Metazoa, we identified 447 groups of orthologous sequences with 21,732 introns in 4,870 unique intron positions. We determined the shared absence and presence of introns in the corresponding sequence alignments and have made this data available in "IntronBase", a web-accessible and downloadable SQLite database. Our results obtained using Dollo Parsimony are obviously misled through systematic errors that arise from multiple intron loss events, but extensive filtering of data improved the quality of the estimated phylogenies. Mutual Information, in contrast, performs better with larger datasets, but at the same time it requires a complete data set, which is difficult to obtain for orthologs from a large number of taxa. Nevertheless, Mutual Information-based distances proved to be useful in analyzing this kind of data, also because the estimation of MI-based distances is independent of evolutionary models and therefore no pre-definitions of ancestral and derived character states are necessary. KW - Mutual Information KW - Evolution KW - Gene structure Y1 - 2013 U6 - https://doi.org/10.1007/s12064-012-0173-0 SN - 1431-7613 VL - 132 IS - 2 SP - 93 EP - 104 PB - Springer CY - New York ER - TY - JOUR A1 - Schröder, Christiane A1 - Pokorny, Ina A1 - Dolgener, Nicola A1 - Herden, Christoph A1 - Drews, Hauke A1 - Tiedemann, Ralph T1 - Allochthonous individuals in managed populations of the fire-bellied toad Bombina bombina genetic detection and conservation implications JF - Limnologica : ecology and management of inland waters N2 - The ongoing global amphibian decline calls for an increase of habitat and population management efforts. Pond restoration and construction is more and more accompanied by breeding and translocation programs. However, the appropriateness of translocations as a tool for conservation has been widely debated, as it can cause biodiversity loss through genetic homogenization and can disrupt local adaptation, eventually leading to outbreeding depression. In this study, we investigated the genetic structure of two translocated populations of the critically endangered fire-bellied toad Bombina bombina at its north western distribution edge using supposedly neutral genetic markers (variation in the mitochondrial control region and microsatellites) as well as a marker under selection (major histocompatibility complex (MHC) genes). While one of the newly established populations showed the typical genetic composition of surrounding populations, the other was extremely diverged without clear affinity to its putative source. In this population we detected a profound impact of allochthonous individuals: 100% of the analyzed individuals exhibited a highly divergent mitochondrial haplotype which was otherwise found in Austria. 83% of them were also assigned to Austria by the analysis of microsatellites. Interestingly, for the adaptive marker (MHC) local alleles were predominant in this population, while only very few alleles were shared with the Austrian population. Probably Mendelian inheritance has reshuffled genotypes such that adaptive local alleles are maintained (here, MHC), while presumably neutral allochthonous alleles dominate at other loci. The release of allochthonous individuals generally increased the genetic variability of the affected population without wiping out locally adaptive genotypes. Thus, outbreeding depression might be less apparent than sometimes thought and natural selection appears strong enough to maintain locally adaptive alleles, at least in functionally important immune system genes. KW - Bombina bombina KW - Microsatellites KW - MHC KW - Mitochondrial DNA KW - Population management KW - Translocation Y1 - 2012 U6 - https://doi.org/10.1016/j.limno.2012.08.008 SN - 0075-9511 VL - 42 IS - 4 SP - 291 EP - 298 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Zhu, Fangjun A1 - Schlupp, Ingo A1 - Tiedemann, Ralph T1 - Allele-specific expression at the androgen receptor alpha gene in a hybrid unisexual fish, the Amazon molly (Poecilia formosa) JF - PLoS one N2 - The all-female Amazon molly (Poecilia formosa) is the result of a hybridization of the Atlantic molly (P. mexicana) and the sailfin molly (P. latipinna) approximately 120,000 years ago. As a gynogenetic species, P. formosa needs to copulate with heterospecific males including males from one of its bisexual ancestral species. However, the sperm only triggers embryogenesis of the diploid eggs. The genetic information of the sperm donor typically will not contribute to the next generation of P. formosa. Hence, P. formosa possesses generally one allele from each of its ancestral species at any genetic locus. This raises the question whether both ancestral alleles are equally expressed in P. formosa. Allele-specific expression (ASE) has been previously assessed in various organisms, e.g., human and fish, and ASE was found to be important in the context of phenotypic variability and disease. In this study, we utilized Real-Time PCR techniques to estimate ASE of the androgen receptor alpha (arα) gene in several distinct tissues of Amazon mollies. We found an allelic bias favoring the maternal ancestor (P. mexicana) allele in ovarian tissue. This allelic bias was not observed in the gill or the brain tissue. Sequencing of the promoter regions of both alleles revealed an association between an Indel in a known CpG island and differential expression. Future studies may reveal whether our observed cis-regulatory divergence is caused by an ovary-specific trans-regulatory element, preferentially activating the allele of the maternal ancestor. Y1 - 2017 U6 - https://doi.org/10.1371/journal.pone.0186411 SN - 1932-6203 VL - 12 IS - 10 SP - 1 EP - 14 PB - PLoS CY - Lawrence, Kan. ER - TY - JOUR A1 - Tiedemann, Ralph A1 - Paulus, Kirsten B. A1 - Havenstein, Katja A1 - Thorstensen, Sverrir A1 - Petersen, Aevar A1 - Lyngs, Peter A1 - Milinkovitch, Michel C. T1 - Alien eggs in duck nests brood parasitism or a help from Grandma? JF - Molecular ecology N2 - Intraspecific brood parasitism (IBP) is a remarkable phenomenon by which parasitic females can increase their reproductive output by laying eggs in conspecific females' nests in addition to incubating eggs in their own nest. Kin selection could explain the tolerance, or even the selective advantage, of IBP, but different models of IBP based on game theory yield contradicting predictions. Our analyses of seven polymorphic autosomal microsatellites in two eider duck colonies indicate that relatedness between host and parasitizing females is significantly higher than the background relatedness within the colony. This result is unlikely to be a by-product of relatives nesting in close vicinity, as nest distance and genetic identity are not correlated. For eider females that had been ring-marked during the decades prior to our study, our analyses indicate that (i) the average age of parasitized females is higher than the age of nonparasitized females, (ii) the percentage of nests with alien eggs increases with the age of nesting females, (iii) the level of IBP increases with the host females' age, and (iv) the number of own eggs in the nest of parasitized females significantly decreases with age. IBP may allow those older females unable to produce as many eggs as they can incubate to gain indirect fitness without impairing their direct fitness: genetically related females specialize in their energy allocation, with young females producing more eggs than they can incubate and entrusting these to their older relatives. Intraspecific brood parasitism in ducks may constitute cooperation among generations of closely related females. KW - eider duck KW - indirect fitness KW - intraspecific brood parasitism KW - microsatellites KW - relatedness KW - Somateria mollissima Y1 - 2011 U6 - https://doi.org/10.1111/j.1365-294X.2011.05158.x SN - 0962-1083 VL - 20 IS - 15 SP - 3237 EP - 3250 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Romero Mujalli, Daniel A1 - Rochow, Markus A1 - Kahl, Sandra A1 - Paraskevopoulou, Sofia A1 - Folkertsma, Remco A1 - Jeltsch, Florian A1 - Tiedemann, Ralph T1 - Adaptive and nonadaptive plasticity in changing environments BT - Implications for sexual species with different life history strategies JF - Ecology and evolution N2 - Populations adapt to novel environmental conditions by genetic changes or phenotypic plasticity. Plastic responses are generally faster and can buffer fitness losses under variable conditions. Plasticity is typically modeled as random noise and linear reaction norms that assume simple one-to- one genotype–phenotype maps and no limits to the phenotypic response. Most studies on plasticity have focused on its effect on population viability. However, it is not clear, whether the advantage of plasticity depends solely on environmental fluctuations or also on the genetic and demographic properties (life histories) of populations. Here we present an individual-based model and study the relative importance of adaptive and nonadaptive plasticity for populations of sexual species with different life histories experiencing directional stochastic climate change. Environmental fluctuations were simulated using differentially autocorrelated climatic stochasticity or noise color, and scenarios of directiona climate change. Nonadaptive plasticity was simulated as a random environmental effect on trait development, while adaptive plasticity as a linear, saturating, or sinusoidal reaction norm. The last two imposed limits to the plastic response and emphasized flexible interactions of the genotype with the environment. Interestingly, this assumption led to (a) smaller phenotypic than genotypic variance in the population (many-to- one genotype–phenotype map) and the coexistence of polymorphisms, and (b) the maintenance of higher genetic variation—compared to linear reaction norms and genetic determinism—even when the population was exposed to a constant environment for several generations. Limits to plasticity led to genetic accommodation, when costs were negligible, and to the appearance of cryptic variation when limits were exceeded. We found that adaptive plasticity promoted population persistence under red environmental noise and was particularly important for life histories with low fecundity. Populations produing more offspring could cope with environmental fluctuations solely by genetic changes or random plasticity, unless environmental change was too fast. KW - developmental canalization KW - environmental change KW - genetic accommodation KW - Individual-based models KW - limits KW - many-to-one genotype–phenotype map KW - noise color KW - phenotypic plasticity KW - reaction norms KW - stochastic fluctuations Y1 - 2020 U6 - https://doi.org/10.1002/ece3.7485 SN - 2045-7758 VL - 11 IS - 11 SP - 6341 EP - 6357 PB - John Wiley & Sons, Inc. CY - New Jersey ER - TY - JOUR A1 - Fiorentino, V. A1 - Manganelli, Giuseppe A1 - Giusti, Folco A1 - Tiedemann, Ralph A1 - Ketmaier, Valerino T1 - A question of time the land snail Murella muralis (Gastropoda: Pulmonata) reveals constraints on past ecological speciation JF - Molecular ecology N2 - The lively debate about speciation currently focuses on the relative importance of factors driving population differentiation. While many studies are increasingly producing results on the importance of selection, little is known about the interaction between drift and selection. Moreover, there is still little knowledge on the spatial-temporal scales at which speciation occurs, that is, arrangement of habitat patches, abruptness of habitat transitions, climate and habitat changes interacting with selective forces. To investigate these questions, we quantified variation on a fine geographical scale analysing morphological (shell) and genetic data sets coupled with environmental data in the land snail Murella muralis, endemic to the Mediterranean island of Sicily. Analysis of a fragment of the mitochondrial DNA cytochrome oxidase I gene (COI) and eight nuclear microsatellite loci showed that genetic variation is highly structured at a very fine spatial scale by local palaeogeographical events and historical population dynamics. Molecular clock estimates, calibrated here specifically for Tyrrhenian land snails, provided a framework of palaeogeographical events responsible for the observed geographical variations and migration routes. Finally, we showed for the first time well-documented lines of evidence of selection in the past, which explains divergence of land snail shell shapes. We suggest that time and palaeogeographical history acted as constraints in the progress along the ecological speciation continuum. Our study shows that testing for correlation among palaeogeography, morphology and genetic data on a fine geographical scale provides information fundamental for a detailed understanding of ecological speciation processes. KW - allopatry KW - cytochrome oxidase I gene KW - ecological speciation KW - land snails KW - microsatellites KW - Murella Y1 - 2013 U6 - https://doi.org/10.1111/mec.12107 SN - 0962-1083 SN - 1365-294X VL - 22 IS - 1 SP - 170 EP - 186 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Spikes, Montrai A1 - Rodríguez-Silva, Rodet A1 - Bennett, Kerri-Ann A1 - Bräger, Stefan A1 - Josaphat, James A1 - Torres-Pineda, Patricia A1 - Ernst, Anja A1 - Havenstein, Katja A1 - Schlupp, Ingo A1 - Tiedemann, Ralph T1 - A phylogeny of the genus Limia (Teleostei: Poeciliidae) suggests a single-lake radiation nested in a Caribbean-wide allopatric speciation scenario JF - BMC Research Notes N2 - Objective The Caribbean is an important global biodiversity hotspot. Adaptive radiations there lead to many speciation events within a limited period and hence are particularly prominent biodiversity generators. A prime example are freshwater fish of the genus Limia, endemic to the Greater Antilles. Within Hispaniola, nine species have been described from a single isolated site, Lake Miragoâne, pointing towards extraordinary sympatric speciation. This study examines the evolutionary history of the Limia species in Lake Miragoâne, relative to their congeners throughout the Caribbean. Results For 12 Limia species, we obtained almost complete sequences of the mitochondrial cytochrome b gene, a well-established marker for lower-level taxonomic relationships. We included sequences of six further Limia species from GenBank (total N  = 18 species). Our phylogenies are in concordance with other published phylogenies of Limia. There is strong support that the species found in Lake Miragoâne in Haiti are monophyletic, confirming a recent local radiation. Within Lake Miragoâne, speciation is likely extremely recent, leading to incomplete lineage sorting in the mtDNA. Future studies using multiple unlinked genetic markers are needed to disentangle the relationships within the Lake Miragoâne clade. KW - Cytochrome b KW - Island biogeography KW - Fresh water fish KW - Phylogeny Y1 - 2021 U6 - https://doi.org/10.1186/s13104-021-05843-x SN - 1756-0500 VL - 14 SP - 1 EP - 8 PB - BMC Research Notes / Biomed Central CY - London ER - TY - JOUR A1 - Bleidorn, Christoph A1 - Lanterbecq, Deborah A1 - Eeckhaut, Igor A1 - Tiedemann, Ralph T1 - A PCR survey of Hox genes in the myzostomid Myzostoma cirriferum N2 - Using degenerate primers, we were able to identify seven Hox genes for the myzostomid Myzostoma cirriferum. The recovered fragments belong to anterior class (Mci_lab, Mci_pb), central class (Mci_Dfd, Mci_Lox5, Mci_Antp, Mci_Lox4), and posterior class (Mci_Post2) paralog groups. Orthology assignment was verified by phylogenetic analyses and presence of diagnostic regions in the homeodomain as well as flanking regions. The presence of Lox5, Lox4, and Post2 supports the inclusion of Myzostomida within Lophotrochozoa. We found signature residues within flanking regions of Lox5, which are also found in annelids, but not in Platyhelminthes. As such the available Hox genes data of myzostomids support an annelid relationship. Y1 - 2009 UR - http://www.springerlink.com/content/100526 U6 - https://doi.org/10.1007/s00427-009-0282-z SN - 0949-944X ER - TY - JOUR A1 - Cheng, Feng A1 - Dennis, Alice B. A1 - Osuoha, Josephine Ijeoma A1 - Canitz, Julia A1 - Kirschbaum, Frank A1 - Tiedemann, Ralph T1 - A new genome assembly of an African weakly electric fish (Campylomormyrus compressirostris, Mormyridae) indicates rapid gene family evolution in Osteoglossomorpha JF - BMC genomics N2 - Background Teleost fishes comprise more than half of the vertebrate species. Within teleosts, most phylogenies consider the split between Osteoglossomorpha and Euteleosteomorpha/Otomorpha as basal, preceded only by the derivation of the most primitive group of teleosts, the Elopomorpha. While Osteoglossomorpha are generally species poor, the taxon contains the African weakly electric fish (Mormyroidei), which have radiated into numerous species. Within the mormyrids, the genus Campylomormyrus is mostly endemic to the Congo Basin. Campylomormyrus serves as a model to understand mechanisms of adaptive radiation and ecological speciation, especially with regard to its highly diverse species-specific electric organ discharges (EOD). Currently, there are few well-annotated genomes available for electric fish in general and mormyrids in particular. Our study aims at producing a high-quality genome assembly and to use this to examine genome evolution in relation to other teleosts. This will facilitate further understanding of the evolution of the osteoglossomorpha fish in general and of electric fish in particular. Results A high-quality weakly electric fish (C. compressirostris) genome was produced from a single individual with a genome size of 862 Mb, consisting of 1,497 contigs with an N50 of 1,399 kb and a GC-content of 43.69%. Gene predictions identified 34,492 protein-coding genes, which is a higher number than in the two other available Osteoglossomorpha genomes of Paramormyrops kingsleyae and Scleropages formosus. A Computational Analysis of gene Family Evolution (CAFE5) comparing 33 teleost fish genomes suggests an overall faster gene family turnover rate in Osteoglossomorpha than in Otomorpha and Euteleosteomorpha. Moreover, the ratios of expanded/contracted gene family numbers in Osteoglossomorpha are significantly higher than in the other two taxa, except for species that had undergone an additional genome duplication (Cyprinus carpio and Oncorhynchus mykiss). As potassium channel proteins are hypothesized to play a key role in EOD diversity among species, we put a special focus on them, and manually curated 16 Kv1 genes. We identified a tandem duplication in the KCNA7a gene in the genome of C. compressirostris. Conclusions We present the fourth genome of an electric fish and the third well-annotated genome for Osteoglossomorpha, enabling us to compare gene family evolution among major teleost lineages. Osteoglossomorpha appear to exhibit rapid gene family evolution, with more gene family expansions than contractions. The curated Kv1 gene family showed seven gene clusters, which is more than in other analyzed fish genomes outside Osteoglossomorpha. The KCNA7a, encoding for a potassium channel central for EOD production and modulation, is tandemly duplicated which may related to the diverse EOD observed among Campylomormyrus species. KW - Campylomormyrus KW - Pacbio sequencing KW - Gene family KW - Osteoglossomorpha KW - Kv1 Y1 - 2023 U6 - https://doi.org/10.1186/s12864-023-09196-6 SN - 1471-2164 VL - 24 IS - 1 PB - BMC CY - London ER - TY - JOUR A1 - Schwarte, Sandra A1 - Tiedemann, Ralph T1 - A Gene Duplication/Loss Event in the Ribulose-1,5-Bisphosphate-Carboxylase/Oxygenase (Rubisco) Small Subunit Gene Family among Accessions of Arabidopsis thaliana JF - Molecular biology and evolution N2 - Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase; EC 4.1.1.39), the most abundant protein in nature, catalyzes the assimilation of CO(2) (worldwide about 10(11) t each year) by carboxylation of ribulose-1,5-bisphosphate. It is a hexadecamer consisting of eight large and eight small subunits. Although the Rubisco large subunit (rbcL) is encoded by a single gene on the multicopy chloroplast genome, the Rubisco small subunits (rbcS) are encoded by a family of nuclear genes. In Arabidopsis thaliana, the rbcS gene family comprises four members, that is, rbcS-1a, rbcS-1b, rbcS-2b, and rbcS-3b. We sequenced all Rubisco genes in 26 worldwide distributed A. thaliana accessions. In three of these accessions, we detected a gene duplication/loss event, where rbcS-1b was lost and substituted by a duplicate of rbcS-2b (called rbcS-2b*). By screening 74 additional accessions using a specific polymerase chain reaction assay, we detected five additional accessions with this duplication/loss event. In summary, we found the gene duplication/loss in 8 of 100 A. thaliana accessions, namely, Bch, Bu, Bur, Cvi, Fei, Lm, Sha, and Sorbo. We sequenced an about 1-kb promoter region for all Rubisco genes as well. This analysis revealed that the gene duplication/loss event was associated with promoter alterations (two insertions of 450 and 850 bp, one deletion of 730 bp) in rbcS-2b and a promoter deletion (2.3 kb) in rbcS-2b* in all eight affected accessions. The substitution of rbcS-1b by a duplicate of rbcS-2b (i.e., rbcS-2b*) might be caused by gene conversion. All four Rubisco genes evolve under purifying selection, as expected for central genes of the highly conserved photosystem of green plants. We inferred a single positive selected site, a tyrosine to aspartic acid substitution at position 72 in rbcS-1b. Exactly the same substitution compromises carboxylase activity in the cyanobacterium Anacystis nidulans. In A. thaliana, this substitution is associated with an inferred recombination. Functional implications of the substitution remain to be evaluated. KW - Arabidopsis thaliana KW - Arabidopsis lyrata KW - Rubisco KW - gene duplication KW - positive selection Y1 - 2011 U6 - https://doi.org/10.1093/molbev/msr008 SN - 0737-4038 VL - 28 IS - 6 SP - 1861 EP - 1876 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Ziege, Madlen A1 - Hennige-Schulz, Carmen A1 - Muecksch, Frauke A1 - Bierbach, David A1 - Tiedemann, Ralph A1 - Streit, Bruno A1 - Plath, Martin T1 - A comparison of two methods to assess audience-induced changes in male mate choice JF - Current zoology N2 - Multidirectional communicative interactions in social networks can have a profound effect on mate choice behavior. Male Atlantic molly Poecilia mexicana exhibit weaker mating preferences when an audience male is presented. This could be a male strategy to reduce sperm competition risk: interacting more equally with different females may be advantageous because rivals might copy mate choice decisions. In line with this hypothesis, a previous study found males to show a strong audience effect when being observed while exercising mate choice, but not when the rival was presented only before the choice tests. Audience effects on mate choice decisions have been quantified in poeciliid fishes using association preference designs, but it remains unknown if patterns found from measuring association times translate into actual mating behavior. Thus, we created five audience treatments simulating different forms of perceived sperm competition risk and determined focal males' mating preferences by scoring pre-mating (nipping) and mating behavior (gonopodial thrusting). Nipping did not reflect the pattern that was found when association preferences were measured, while a very similar pattern was uncovered in thrusting behavior. The strongest response was observed when the audience could eavesdrop on the focal male's behavior. A reduction in the strength of focal males' preferences was also seen after the rival male had an opportunity to mate with the focal male's preferred mate. In comparison, the reduction of mating preferences in response to an audience was greater when measuring association times than actual mating behavior. While measuring direct sexual interactions between the focal male and both stimulus females not only the male's motivational state is reflected but also females' behavior such as avoidance of male sexual harassment. KW - Communication networks KW - Male mate choice KW - Non-independent mate choice KW - Sexual selection KW - Sperm competition risk KW - Audience effect Y1 - 2012 SN - 1674-5507 VL - 58 IS - 1 SP - 84 EP - 94 PB - Current Zoology CY - Beijing ER - TY - JOUR A1 - Stoof-Leichsenring, Kathleen Rosemarie A1 - Bernhardt, Nadine A1 - Pestryakova, Luidmila Agafyevna A1 - Epp, Laura Saskia A1 - Herzschuh, Ulrike A1 - Tiedemann, Ralph T1 - A combined paleolimnological/genetic analysis of diatoms reveals divergent evolutionary lineages of Staurosira and Staurosirella (Bacillariophyta) in Siberian lake sediments along a latitudinal transect JF - Journal of paleolimnolog N2 - Diatom diversity in lakes of northwest Yakutia (Siberia) was investigated by microscopic and genetic analysis of surface and cored lake sediments, to evaluate the use of sedimentary DNA for paleolimnological diatom studies and to identify obscure genetic diversity that cannot be detected by microscopic methods. Two short (76 and 73 bp) and one longer (577 bp) fragments of the ribulose 1,5-bisphosphate carboxylase/oxygenase (rbcL) gene, encoding the large subunit of the rbcL, were used as genetic markers. Diverse morphological assemblages of diatoms, dominated by small benthic fragilarioid taxa, were retrieved from the sediments of each lake. These minute fragilarioid taxa were examined by scanning electron microscopy, revealing diverse morphotypes in Staurosira and Staurosirella from the different lakes. Genetic analyses indicated a dominance of haplotypes that were assigned to fragilarioid taxa and less genetic diversity in other diatom taxa. The long rbcL_577 amplicon identified considerable diversification among haplotypes clustering within the Staurosira/Staurosirella genera, revealing 19 different haplotypes whose spatial distribution appears to be primarily related to the latitude of the lakes, which corresponds to a vegetation and climate gradient. Our rbcL markers are valuable tools for tracking differences between diatom lineages that are not visible in their morphologies. These markers revealed putatively high genetic diversity within the Staurosira/Staurosirella species complex, at a finer scale than is possible to resolve by microscopic determination. The rbcL markers may provide additional reliable information on the diversity of barely distinguishable minute benthic fragilarioids. Environmental sequencing may thus allow the tracking of spatial and temporal diversification in Siberian lakes, especially in the context of diatom responses to recent environmental changes, which remains a matter of controversy. KW - Arctic lake sediments KW - Diatoms KW - Environmental DNA KW - Intraspecific variation KW - RbcL Y1 - 2014 U6 - https://doi.org/10.1007/s10933-014-9779-1 SN - 0921-2728 SN - 1573-0417 VL - 52 IS - 1-2 SP - 77 EP - 93 PB - Springer CY - Dordrecht ER -