@article{KiemelGurkeParaskevopoulouetal.2022,
  author    = {Kiemel, Katrin and Gurke, Marie and Paraskevopoulou, Sofia and Havenstein, Katja and Weithoff, Guntram and Tiedemann, Ralph},
  title     = {Variation in heat shock protein 40 kDa relates to divergence in thermotolerance among cryptic rotifer species},
  series = {Scientific reports},
  volume    = {12},
  journal   = {Scientific reports},
  number    = {1},
  publisher = {Macmillan Publishers Limited},
  address   = {London},
  issn      = {2045-2322},
  doi       = {10.1038/s41598-022-27137-3},
  pages     = {14},
  year      = {2022},
  abstract  = {Genetic divergence and the frequency of hybridization are central for defining species delimitations, especially among cryptic species where morphological differences are merely absent. Rotifers are known for their high cryptic diversity and therefore are ideal model organisms to investigate such patterns. Here, we used the recently resolved Brachionus calyciflorus species complex to investigate whether previously observed between species differences in thermotolerance and gene expression are also reflected in their genomic footprint. We identified a Heat Shock Protein gene (HSP 40 kDa) which exhibits cross species pronounced sequence variation. This gene exhibits species-specific fixed sites, alleles, and sites putatively under positive selection. These sites are located in protein binding regions involved in chaperoning and may therefore reflect adaptive diversification. By comparing three genetic markers (ITS, COI, HSP 40 kDa), we revealed hybridization events between the cryptic species. The low frequency of introgressive haplotypes/alleles suggest a tight, but not fully impermeable boundary between the cryptic species.},
  language  = {en}
}
@article{CanitzKirschbaumTiedemann2020,
  author    = {Canitz, Julia and Kirschbaum, Frank and Tiedemann, Ralph},
  title     = {Transcriptome-wide single nucleotide polymorphisms related to electric organ discharge differentiation among African weakly electric fish species},
  series = {PLoS one},
  volume    = {15},
  journal   = {PLoS one},
  number    = {10},
  publisher = {PLoS},
  address   = {San Francisco, California, US},
  issn      = {1932-6203},
  doi       = {10.1371/journal.pone.0240812},
  pages     = {21},
  year      = {2020},
  abstract  = {African weakly electric fish of the mormyrid genus Campylomormyrus generate pulse-type electric organ discharges (EODs) for orientation and communication. Their pulse durations are species-specific and elongated EODs are a derived trait. So far, differential gene expression among tissue-specific transcriptomes across species with different pulses and point mutations in single ion channel genes indicate a relation of pulse duration and electrocyte geometry/excitability. However, a comprehensive assessment of expressed Single Nucleotide Polymorphisms (SNPs) throughout the entire transcriptome of African weakly electric fish, with the potential to identify further genes influencing EOD duration, is still lacking. This is of particular value, as discharge duration is likely based on multiple cellular mechanisms and various genes. Here we provide the first transcriptome-wide SNP analysis of African weakly electric fish species (genus Campylomormyrus) differing by EOD duration to identify candidate genes and cellular mechanisms potentially involved in the determination of an elongated discharge of C. tshokwe. Non-synonymous substitutions specific to C. tshokwe were found in 27 candidate genes with inferred positive selection among Campylomormyrus species. These candidate genes had mainly functions linked to transcriptional regulation, cell proliferation and cell differentiation. Further, by comparing gene annotations between C. compressirostris (ancestral short EOD) and C. tshokwe (derived elongated EOD), we identified 27 GO terms and 2 KEGG pathway categories for which C. tshokwe significantly more frequently exhibited a species-specific expressed substitution than C. compressirostris. The results indicate that transcriptional regulation as well cell proliferation and differentiation take part in the determination of elongated pulse durations in C. tshokwe. Those cellular processes are pivotal for tissue morphogenesis and might determine the shape of electric organs supporting the observed correlation between electrocyte geometry/tissue structure and discharge duration. The inferred expressed SNPs and their functional implications are a valuable resource for future investigations on EOD durations.},
  language  = {en}
}
@article{SchedinaGrothSchluppetal.2018,
  author    = {Schedina, Ina Maria and Groth, Detlef and Schlupp, Ingo and Tiedemann, Ralph},
  title     = {The gonadal transcriptome of the unisexual Amazon molly Poecilia formosa in comparison to its sexual ancestors, Poecilia mexicana and Poecilia latipinna},
  series = {BMC Genomics},
  volume    = {19},
  journal   = {BMC Genomics},
  number    = {12},
  publisher = {BioMed Central},
  address   = {London},
  issn      = {1471-2164},
  doi       = {10.1186/s12864-017-4382-2},
  pages     = {1 -- 18},
  year      = {2018},
  abstract  = {Background The unisexual Amazon molly (Poecilia formosa) originated from a hybridization between two sexual species, the sailfin molly (Poecilia latipinna) and the Atlantic molly (Poecilia mexicana). The Amazon molly reproduces clonally via sperm-dependent parthenogenesis (gynogenesis), in which the sperm of closely related species triggers embryogenesis of the apomictic oocytes, but typically does not contribute genetic material to the next generation. We compare for the first time the gonadal transcriptome of the Amazon molly to those of both ancestral species, P. mexicana and P. latipinna. Results We sequenced the gonadal transcriptomes of the P. formosa and its parental species P. mexicana and P. latipinna using Illumina RNA-sequencing techniques (paired-end, 100 bp). De novo assembly of about 50 million raw read pairs for each species was performed using Trinity, yielding 106,922 transcripts for P. formosa, 115,175 for P. latipinna, and 133,025 for P. mexicana after eliminating contaminations. On the basis of sequence similarity comparisons to other teleost species and the UniProt databases, functional annotation, and differential expression analysis, we demonstrate the similarity of the transcriptomes among the three species. More than 40\% of the transcripts for each species were functionally annotated and about 70\% were assigned to orthologous genes of a closely related species. Differential expression analysis between the sexual and unisexual species uncovered 2035 up-regulated and 564 down-regulated genes in P. formosa. This was exemplary validated for six genes by qRT-PCR. Conclusions We identified more than 130 genes related to meiosis and reproduction within the apomictically reproducing P. formosa. Overall expression of these genes seems to be down-regulated in the P. formosa transcriptome compared to both ancestral species (i.e., 106 genes down-regulated, 29 up-regulated). A further 35 meiosis and reproduction related genes were not found in the P. formosa transcriptome, but were only expressed in the sexual species. Our data support the hypothesis of general down-regulation of meiosis-related genes in the apomictic Amazon molly. Furthermore, the obtained dataset and identified gene catalog will serve as a resource for future research on the molecular mechanisms behind the reproductive mode of this unisexual species.},
  language  = {en}
}
@misc{SchedinaGrothSchluppetal.2018,
  author    = {Schedina, Ina Maria and Groth, Detlef and Schlupp, Ingo and Tiedemann, Ralph},
  title     = {The gonadal transcriptome of the unisexual Amazon molly Poecilia formosa in comparison to its sexual ancestors, Poecilia mexicana and Poecilia latipinna},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-409299},
  pages     = {18},
  year      = {2018},
  abstract  = {Abstract Background The unisexual Amazon molly (Poecilia formosa) originated from a hybridization between two sexual species, the sailfin molly (Poecilia latipinna) and the Atlantic molly (Poecilia mexicana). The Amazon molly reproduces clonally via sperm-dependent parthenogenesis (gynogenesis), in which the sperm of closely related species triggers embryogenesis of the apomictic oocytes, but typically does not contribute genetic material to the next generation. We compare for the first time the gonadal transcriptome of the Amazon molly to those of both ancestral species, P. mexicana and P. latipinna. Results We sequenced the gonadal transcriptomes of the P. formosa and its parental species P. mexicana and P. latipinna using Illumina RNA-sequencing techniques (paired-end, 100 bp). De novo assembly of about 50 million raw read pairs for each species was performed using Trinity, yielding 106,922 transcripts for P. formosa, 115,175 for P. latipinna, and 133,025 for P. mexicana after eliminating contaminations. On the basis of sequence similarity comparisons to other teleost species and the UniProt databases, functional annotation, and differential expression analysis, we demonstrate the similarity of the transcriptomes among the three species. More than 40\% of the transcripts for each species were functionally annotated and about 70\% were assigned to orthologous genes of a closely related species. Differential expression analysis between the sexual and unisexual species uncovered 2035 up-regulated and 564 down-regulated genes in P. formosa. This was exemplary validated for six genes by qRT-PCR. Conclusions We identified more than 130 genes related to meiosis and reproduction within the apomictically reproducing P. formosa. Overall expression of these genes seems to be down-regulated in the P. formosa transcriptome compared to both ancestral species (i.e., 106 genes down-regulated, 29 up-regulated). A further 35 meiosis and reproduction related genes were not found in the P. formosa transcriptome, but were only expressed in the sexual species. Our data support the hypothesis of general down-regulation of meiosis-related genes in the apomictic Amazon molly. Furthermore, the obtained dataset and identified gene catalog will serve as a resource for future research on the molecular mechanisms behind the reproductive mode of this unisexual species.},
  language  = {en}
}
@article{DeCahsanWestburyDrewsetal.2019,
  author    = {De Cahsan, Binia and Westbury, Michael V. and Drews, Hauke and Tiedemann, Ralph},
  title     = {The complete mitochondrial genome of a European fire-bellied toad (Bombina bombina) from Germany},
  series = {Mitochondrial DNA Part B},
  volume    = {4},
  journal   = {Mitochondrial DNA Part B},
  number    = {1},
  publisher = {Taylor \& Francis Group},
  address   = {London},
  issn      = {2380-2359},
  doi       = {10.1080/23802359.2018.1547143},
  pages     = {498 -- 500},
  year      = {2019},
  abstract  = {The European fire-bellied toad, Bombina bombina, is a small aquatic toad belonging to the family Bombinatoridae. The species is native to the lowlands of Central and Eastern Europe, where population numbers have been in decline in recent past decades. Here, we present the first complete mitochondrial genome of the endangered European fire-bellied toad from Northern Germany recovered using iterative mapping. Phylogenetic analyses including other representatives of the Bombinatoridae placed our German specimen as sister to a Polish B. bombina sequence with high support. This finding is congruent with the postulated Pleistocene history of the species. Our complete mitochondrial genome represents an important resource for further population analysis of the European fire-bellied toad, especially those found within Germany.},
  language  = {en}
}
@misc{DeCahsanWestburyDrewsetal.2019,
  author    = {De Cahsan, Binia and Westbury, Michael V. and Drews, Hauke and Tiedemann, Ralph},
  title     = {The complete mitochondrial genome of a European fire-bellied toad (Bombina bombina) from Germany},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {532},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-42322},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-423222},
  pages     = {3},
  year      = {2019},
  abstract  = {The European fire-bellied toad, Bombina bombina, is a small aquatic toad belonging to the family Bombinatoridae. The species is native to the lowlands of Central and Eastern Europe, where population numbers have been in decline in recent past decades. Here, we present the first complete mitochondrial genome of the endangered European fire-bellied toad from Northern Germany recovered using iterative mapping. Phylogenetic analyses including other representatives of the Bombinatoridae placed our German specimen as sister to a Polish B. bombina sequence with high support. This finding is congruent with the postulated Pleistocene history of the species. Our complete mitochondrial genome represents an important resource for further population analysis of the European fire-bellied toad, especially those found within Germany.},
  language  = {en}
}
@article{SchnitzlerReckendorfPinzoneetal.2018,
  author    = {Schnitzler, Joseph G. and Reckendorf, Anja and Pinzone, Marianna and Autenrieth, Marijke and Tiedemann, Ralph and Covaci, Adrian and Malarvannan, Govindan and Ruser, Andreas and Das, Krishna and Siebert, Ursula},
  title     = {Supporting evidence for PCB pollution threatening global killer whale population},
  series = {Aquatic Toxicology},
  volume    = {206},
  journal   = {Aquatic Toxicology},
  publisher = {Elsevier},
  address   = {Amsterdam},
  issn      = {0166-445X},
  doi       = {10.1016/j.aquatox.2018.11.008},
  pages     = {102 -- 104},
  year      = {2018},
  abstract  = {A recent Science report predicted the global killer whale population to collapse due to PCB pollution. Here we present empirical evidence, which supports and extends the reports' statement. In 2016, a neonate male killer whale stranded on the German island of Sylt. Neonatal attributes indicated an age of at least 3 days. The stomach contained ∼20 mL milk residue and no pathologies explaining the cause of death could be detected. Blubber samples presenting low lipid concentrations were analysed for persistent organic pollutants. Skin samples were collected for genotyping of the mitochondrial control region. The blubber PCB concentrations were very high [SPCBs, 225 mg/kg lipid weight (lw)], largely exceeding the PCB toxicity thresholds reported for the onset of immunosuppression [9 mg/kg lw ∑PCB] and for severe reproductive impairment [41 mg/kg lw ∑PCB] reported for marine mammals. Additionally, this individual showed equally high concentrations in p,p'-DDE [226 mg/kg lw], PBDEs [5 mg/kg lw] and liver mercury levels [1.1 μg/g dry weight dw]. These results suggest a high placental transfer of pollutants from mother to foetus. Consequently, blubber and plasma PCB concentrations and calf mortality rates are both high in primiparous females. With such high pollutant levels, this neonate had poor prerequisites for survival. The neonate belonged to Ecotype I (generalist feeder) and carried the mitochondrial haplotype 35 present in about 16\% of the North Atlantic killer whale from or close to the North Sea. The relevance of this data becomes apparent in the UK West Coast Community, the UK's only residentorca population, which is currently composed of only eight individuals (each four males and females) and no calves have been reported over the last 19 years.Despite worldwide regulations, PCBs persist in the environment and remain a severe concern for killer whale populations, placing calves at high risk due to the mother-offspring PCB-transfer resulting in a high toxicological burden of the neonates.},
  language  = {en}
}
@article{SenczukHavensteinMilanaetal.2018,
  author    = {Senczuk, Gabriele and Havenstein, Katja and Milana, Valentina and Ripa, Chiara and De Simone, Emanuela and Tiedemann, Ralph and Castiglia, Riccardo},
  title     = {Spotlight on islands},
  series = {Scientific reports},
  volume    = {8},
  journal   = {Scientific reports},
  publisher = {Nature Publ. Group},
  address   = {London},
  issn      = {2045-2322},
  doi       = {10.1038/s41598-018-33326-w},
  pages     = {12},
  year      = {2018},
  abstract  = {Groups of proximate continental islands may conceal more tangled phylogeographic patterns than oceanic archipelagos as a consequence of repeated sea level changes, which allow populations to experience gene flow during periods of low sea level stands and isolation by vicariant mechanisms during periods of high sea level stands. Here, we describe for the first time an ancient and diverging lineage of the Italian wall lizard Podarcis siculus from the western Pontine Islands. We used nuclear and mitochondrial DNA sequences of 156 individuals with the aim of unraveling their phylogenetic position, while microsatellite loci were used to test several a priori insular biogeographic models of migration with empirical data. Our results suggest that the western Pontine populations colonized the islands early during their Pliocene volcanic formation, while populations from the eastern Pontine Islands seem to have been introduced recently. The inter-island genetic makeup indicates an important role of historical migration, probably due to glacial land bridges connecting islands followed by a recent vicariant mechanism of isolation. Moreover, the most supported migration model predicted higher gene flow among islands which are geographically arranged in parallel. Considering the threatened status of small insular endemic populations, we suggest this new evolutionarily independent unit be given priority in conservation efforts.},
  language  = {en}
}
@misc{CahsanKiemelWestburyetal.2021,
  author    = {Cahsan, Binia De and Kiemel, Katrin and Westbury, Michael V. and Lauritsen, Maike and Autenrieth, Marijke and Gollmann, G{\"u}nter and Schweiger, Silke and Stenberg, Marika and Nystr{\"o}m, Per and Drews, Hauke and Tiedemann, Ralph},
  title     = {Southern introgression increases adaptive immune gene variability in northern range margin populations of Fire-bellied toad},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  number    = {14},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-52388},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-523883},
  pages     = {17},
  year      = {2021},
  abstract  = {Northern range margin populations of the European fire-bellied toad (Bombina bombina) have rapidly declined during recent decades. Extensive agricultural land use has fragmented the landscape, leading to habitat disruption and loss, as well as eutrophication of ponds. In Northern Germany (Schleswig-Holstein) and Southern Sweden (Sk{\aa}ne), this population decline resulted in decreased gene flow from surrounding populations, low genetic diversity, and a putative reduction in adaptive potential, leaving populations vulnerable to future environmental and climatic changes. Previous studies using mitochondrial control region and nuclear transcriptome-wide SNP data detected introgressive hybridization in multiple northern B. bombina populations after unreported release of toads from Austria. Here, we determine the impact of this introgression by comparing the body conditions (proxy for fitness) of introgressed and nonintrogressed populations and the genetic consequences in two candidate genes for putative local adaptation (the MHC II gene as part of the adaptive immune system and the stress response gene HSP70 kDa). We detected regional differences in body condition and observed significantly elevated levels of within individual MHC allele counts in introgressed Swedish populations, associated with a tendency toward higher body weight, relative to regional nonintrogressed populations. These differences were not observed among introgressed and nonintrogressed German populations. Genetic diversity in both MHC and HSP was generally lower in northern than Austrian populations. Our study sheds light on the potential benefits of translocations of more distantly related conspecifics as a means to increase adaptive genetic variability and fitness of genetically depauperate range margin populations without distortion of local adaptation.},
  language  = {en}
}
@article{CahsanKiemelWestburyetal.2021,
  author    = {Cahsan, Binia De and Kiemel, Katrin and Westbury, Michael V. and Lauritsen, Maike and Autenrieth, Marijke and Gollmann, G{\"u}nter and Schweiger, Silke and Stenberg, Marika and Nystr{\"o}m, Per and Drews, Hauke and Tiedemann, Ralph},
  title     = {Southern introgression increases adaptive immune gene variability in northern range margin populations of Fire-bellied toad},
  series = {Ecology and Evolution},
  volume    = {11},
  journal   = {Ecology and Evolution},
  number    = {14},
  publisher = {John Wiley \& Sons, Inc.},
  address   = {New Jersey},
  issn      = {2045-7758},
  pages     = {15},
  year      = {2021},
  abstract  = {Northern range margin populations of the European fire-bellied toad (Bombina bombina) have rapidly declined during recent decades. Extensive agricultural land use has fragmented the landscape, leading to habitat disruption and loss, as well as eutrophication of ponds. In Northern Germany (Schleswig-Holstein) and Southern Sweden (Sk{\aa}ne), this population decline resulted in decreased gene flow from surrounding populations, low genetic diversity, and a putative reduction in adaptive potential, leaving populations vulnerable to future environmental and climatic changes. Previous studies using mitochondrial control region and nuclear transcriptome-wide SNP data detected introgressive hybridization in multiple northern B. bombina populations after unreported release of toads from Austria. Here, we determine the impact of this introgression by comparing the body conditions (proxy for fitness) of introgressed and nonintrogressed populations and the genetic consequences in two candidate genes for putative local adaptation (the MHC II gene as part of the adaptive immune system and the stress response gene HSP70 kDa). We detected regional differences in body condition and observed significantly elevated levels of within individual MHC allele counts in introgressed Swedish populations, associated with a tendency toward higher body weight, relative to regional nonintrogressed populations. These differences were not observed among introgressed and nonintrogressed German populations. Genetic diversity in both MHC and HSP was generally lower in northern than Austrian populations. Our study sheds light on the potential benefits of translocations of more distantly related conspecifics as a means to increase adaptive genetic variability and fitness of genetically depauperate range margin populations without distortion of local adaptation.},
  language  = {en}
}
@misc{NeyeWallschlaegerTiedemann2006,
  author    = {Neye, Gundula and Wallschl{\"a}ger, Hans-Dieter and Tiedemann, Ralph},
  title     = {Song dialect boundaries in the Yellowhammer: Do they restrict gene flow?},
  series = {Journal of ornithology},
  volume    = {147},
  journal   = {Journal of ornithology},
  number    = {Supplement 1},
  publisher = {Blackwell},
  address   = {New York},
  issn      = {0021-8375},
  pages     = {219 -- 219},
  year      = {2006},
  language  = {en}
}
@misc{StieglerKiemelEccardetal.2021,
  author    = {Stiegler, Jonas and Kiemel, Katrin and Eccard, Jana and Fischer, Christina and Hering, Robert and Ortmann, Sylvia and Strigl, Lea and Tiedemann, Ralph},
  title     = {Seed traits matter},
  series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-54426},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-544265},
  pages     = {18477 -- 18491},
  year      = {2021},
  abstract  = {Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51\%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.},
  language  = {en}
}
@article{StieglerKiemelEccardetal.2021,
  author    = {Stiegler, Jonas and Kiemel, Katrin and Eccard, Jana and Fischer, Christina and Hering, Robert and Ortmann, Sylvia and Strigl, Lea and Tiedemann, Ralph},
  title     = {Seed traits matter},
  series = {Ecology and Evolution},
  volume    = {11},
  journal   = {Ecology and Evolution},
  number    = {24},
  publisher = {John Wiley \& Sons, Inc.},
  issn      = {2045-7758},
  doi       = {10.1002/ece3.8440},
  pages     = {18477 -- 18491},
  year      = {2021},
  abstract  = {Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51\%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.},
  language  = {en}
}
@article{StieglerKiemelEccardetal.2021,
  author    = {Stiegler, Jonas and Kiemel, Katrin and Eccard, Jana and Fischer, Christina and Hering, Robert and Ortmann, Sylvia and Strigl, Lea and Tiedemann, Ralph and Ullmann, Wiebke and Blaum, Niels},
  title     = {Seed traits matter},
  series = {Ecology and evolution},
  volume    = {11},
  journal   = {Ecology and evolution},
  number    = {24},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {2045-7758},
  doi       = {10.1002/ece3.8440},
  pages     = {18477 -- 18491},
  year      = {2021},
  abstract  = {Although many plants are dispersed by wind and seeds can travel long distances across unsuitable matrix areas, a large proportion relies on co-evolved zoochorous seed dispersal to connect populations in isolated habitat islands. Particularly in agricultural landscapes, where remaining habitat patches are often very small and highly isolated, mobile linkers as zoochorous seed dispersers are critical for the population dynamics of numerous plant species. However, knowledge about the quali- or quantification of such mobile link processes, especially in agricultural landscapes, is still limited. In a controlled feeding experiment, we recorded the seed intake and germination success after complete digestion by the European brown hare (Lepus europaeus) and explored its mobile link potential as an endozoochoric seed disperser. Utilizing a suite of common, rare, and potentially invasive plant species, we disentangled the effects of seed morphological traits on germination success while controlling for phylogenetic relatedness. Further, we measured the landscape connectivity via hares in two contrasting agricultural landscapes (simple: few natural and semi-natural structures, large fields; complex: high amount of natural and semi-natural structures, small fields) using GPS-based movement data. With 34,710 seeds of 44 plant species fed, one of 200 seeds (0.51\%) with seedlings of 33 species germinated from feces. Germination after complete digestion was positively related to denser seeds with comparatively small surface area and a relatively slender and elongated shape, suggesting that, for hares, the most critical seed characteristics for successful endozoochorous seed dispersal minimize exposure of the seed to the stomach and the associated digestive system. Furthermore, we could show that a hare's retention time is long enough to interconnect different habitats, especially grasslands and fields. Thus, besides other seed dispersal mechanisms, this most likely allows hares to act as effective mobile linkers contributing to ecosystem stability in times of agricultural intensification, not only in complex but also in simple landscapes.},
  language  = {en}
}
@article{GessnerArndtTiedemannetal.2006,
  author    = {Gessner, J{\"o}rn and Arndt, Gerd-Michael and Tiedemann, Ralph and Bartel, Ryszard and Kirschbaum, Frank},
  title     = {Remediation measures for the Baltic sturgeon: status review and perspectives},
  series = {Journal of applied ichthyology},
  volume    = {22},
  journal   = {Journal of applied ichthyology},
  number    = {S1},
  publisher = {Wiley-Blackwell},
  address   = {Oxford},
  issn      = {0175-8659},
  doi       = {10.1111/j.1439-0426.2007.00925.x},
  pages     = {23 -- 31},
  year      = {2006},
  abstract  = {More than one century ago, sturgeons were prevalent species in the fish communities of all major German rivers both in the North and the Baltic seas drainages. Since then, the populations declined rapidly due to river damming, overfishing and pollution. The last sturgeon catches in the Baltic drainage system occurred during the late 1960ies. Only a few individual captures have been reported during the last 30 years with the most recent records in the Lake Ladoga ( Russia), where the last confirmed catch was recorded in 1984, and a single individual caught off Estonia in 1996. Today, sturgeons are considered missing or extinct in German waters. First attempts for remediation of the species were undertaken in the mid 1990ies. Subsequently, phylogenetic and population genetic analyses of the species were carried out using mtDNA, microsatellites, and nuclear markers ( SNPs). These genetic analyses using recent and historic material have proven the existence of two different species in the Baltic Sea in what was previously considered to represent the European Atlantic sturgeon only. In the Baltic Sea, the American Atlantic sturgeon ( A. oxyrinchus) succeeded to colonize this brackish water system during the Middle Ages. In the North Sea, the European Atlantic sturgeon ( A. sturio) is considered to be the endemic species. These results led to the separation of the remediation activities in the North Sea and the Baltic Sea tributaries. Further studies on the mechanism that lead to the extinction of A. sturio in Germany and the subsequent succession of the A. oxyrinchus mtDNA haplotype are currently been carried out. Broodstock development using the northernmost populations of A. oxyrinchus is currently under way. As a further prerequisite to re-introduce this species into the Baltic, the evaluation of the status of critical habitats for the early life stages of the American Atlantic sturgeon in the River Odra has been performed in collaboration with the Institute for Inland Fisheries of Poland. Alternative fisheries techniques, based on the data of by-catch of exotic sturgeons in the fishery, are presently developed in close cooperation with the fishery to reduce fisheries related mortality in juvenile sturgeons upon release. Monitoring of habitat utilization and migration characteristics of juvenile fish upon experimental release will have to be carried out shortly, using acoustic telemetry, with the aim to follow the fate of the released fish and to determine the best time-size-release-window for future release programmes.},
  language  = {en}
}
@misc{AutenriethErnstDeavilleetal.2018,
  author    = {Autenrieth, Marijke and Ernst, Anja and Deaville, Rob and Demaret, Fabien and Ijsseldijk, Lonneke L. and Siebert, Ursula and Tiedemann, Ralph},
  title     = {Putative origin and maternal relatedness of male sperm whales (Physeter macrocephalus) recently stranded in the North Sea},
  series = {Mammalian biology = Zeitschrift f{\"u}r S{\"a}ugetierkunde},
  volume    = {88},
  journal   = {Mammalian biology = Zeitschrift f{\"u}r S{\"a}ugetierkunde},
  publisher = {Elsevier},
  address   = {M{\"u}nchen},
  issn      = {1616-5047},
  doi       = {10.1016/j.mambio.2017.09.003},
  pages     = {156 -- 160},
  year      = {2018},
  abstract  = {The globally distributed sperm whale (Physeter macrocephalus) has a partly matrilineal social structure with predominant male dispersal. At the beginning of 2016, a total of 30 male sperm whales stranded in five different countries bordering the southern North Sea. It has been postulated that these individuals were on a migration route from the north to warmer temperate and tropical waters where females live in social groups. By including samples from four countries (n = 27), this event provided a unique chance to genetically investigate the maternal relatedness and the putative origin of these temporally and spatially co-occuring male sperm whales. To utilize existing genetic resources, we sequenced 422 bp of the mitochondrial control region, a molecular marker for which sperm whale data are readily available from the entire distribution range. Based on four single nucleotide polymorphisms (SNPs) within the mitochondrial control region, five matrilines could be distinguished within the stranded specimens, four of which matched published haplotypes previously described in the Atlantic. Among these male sperm whales, multiple matrilineal lineages co-occur. We analyzed the population differentiation and could show that the genetic diversity of these male sperm whales is comparable to the genetic diversity in sperm whales from the entire Atlantic Ocean. We confirm that within this stranding event, males do not comprise maternally related individuals and apparently include assemblages of individuals from different geographic regions. (c) 2017 Deutsche Gesellschaft fur Saugetierkunde. Published by Elsevier GmbH. All rights reserved.},
  language  = {en}
}
@article{TaguchiGotoMatsuokaetal.2023,
  author    = {Taguchi, Mioko and Goto, Mutsuo and Matsuoka, Koji and Tiedemann, Ralph and Pastene, Luis A.},
  title     = {Population genetic structure of Bryde's whales (Balaenoptera brydei) on the central and western North Pacific feeding grounds},
  series = {Canadian Journal of Fisheries and Aquatic Sciences},
  volume    = {80},
  journal   = {Canadian Journal of Fisheries and Aquatic Sciences},
  number    = {1},
  publisher = {Canadian science publishing},
  address   = {Ottawa},
  issn      = {0706-652X},
  doi       = {10.1139/cjfas-2022-0005},
  pages     = {142 -- 155},
  year      = {2023},
  abstract  = {The genetic structure of Bryde's whale (Balaenoptera brydei) on the central and western North Pacific feeding grounds was investigated using a total of 1195 mitochondrial control region sequences and 1182 microsatellite genotypes at 17 loci in specimens collected from three longitudinal areas, 1W (135 degrees E-165 degrees E), 1E (165 degrees E-180 degrees), and 2 (180 degrees-155 degrees W). Genetic diversities were similar among areas and a haplotype network did not show any geographic structure, while an analysis of molecular variance found evidence of genetic structure in this species. Pairwise FST and G'ST estimates and heterogeneity tests attributed this structure to weak but significant differentiation between areas 1W/1E and 2. A Mantel test and a high-resolution analysis of genetic diversity statistics showed a weak spatial cline of genetic differentiation. These findings could be reconciled by two possible stock structure scenarios: (1) a single population with kin-association affecting feeding ground preference and (2) two populations with feeding ground preference for either area 1W or area 2. An estimated dispersal rate between areas 1W and 2 indicates that both scenarios should be considered as a precautionary principle in stock assessments.},
  language  = {en}
}
@article{KorniienkoTiedemannVateretal.2020,
  author    = {Korniienko, Yevheniia and Tiedemann, Ralph and Vater, Marianne and Kirschbaum, Frank},
  title     = {Ontogeny of the electric organ discharge and of the papillae of the electrocytes in the weakly electric fish Campylomormyrus rhynchophorus (Teleostei: Mormyridae)},
  series = {The journal of comparative neurology},
  volume    = {529},
  journal   = {The journal of comparative neurology},
  number    = {5},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {0021-9967},
  doi       = {10.1002/cne.25003},
  pages     = {1052 -- 1065},
  year      = {2020},
  abstract  = {The electric organ of the mormyrid weakly electric fish,Campylomormyrus rhynchophorus(Boulenger, 1898), undergoes changes in both the electric organ discharge (EOD) and the light and electron microscopic morphology as the fish mature from the juvenile to the adult form. Of particular interest was the appearance of papillae, surface specializations of the uninnervated anterior face of the electrocyte, which have been hypothesized to increase the duration of the EOD. In a 24.5 mm long juvenile the adult electric organ (EO) was not yet functional, and the electrocytes lacked papillae. A 40 mm long juvenile, which produced a short biphasic EOD of 1.3 ms duration, shows small papillae (average area 136 mu m(2)). In contrast, the EOD of a 79 mm long juvenile was triphasic. The large increase in duration of the EOD to 23.2 ms was accompanied by a small change in size of the papillae (average area 159 mu m(2)). Similarly, a 150 mm long adult produced a triphasic EOD of comparable duration to the younger stage (24.7 ms) but featured a prominent increase in size of the papillae (average area 402 mu m(2)). Thus, there was no linear correlation between EOD duration and papillary size. The most prominent ultrastructural change was at the level of the myofilaments, which regularly extended into the papillae, only in the oldest specimen-probably serving a supporting function. Physiological mechanisms, like gene expression levels, as demonstrated in someCampylomormyrusspecies, might be more important concerning the duration of the EOD.},
  language  = {en}
}
@article{NguyenMamonekeneVateretal.2020,
  author    = {Nguyen, Manh Duy Linh and Mamonekene, Victor and Vater, Marianne and Bartsch, Peter and Tiedemann, Ralph and Kirschbaum, Frank},
  title     = {Ontogeny of electric organ and electric organ discharge in Campylomormyrus rhynchophorus (Teleostei: Mormyridae)},
  series = {Journal of comparative physiology; A, Neuroethology, sensory, neural, and behavioral physiology},
  volume    = {206},
  journal   = {Journal of comparative physiology; A, Neuroethology, sensory, neural, and behavioral physiology},
  number    = {3},
  publisher = {Springer},
  address   = {Berlin ; Heidelberg},
  issn      = {0340-7594},
  doi       = {10.1007/s00359-020-01411-z},
  pages     = {453 -- 466},
  year      = {2020},
  abstract  = {The aim of this study was a longitudinal description of the ontogeny of the adult electric organ of Campylomormyrus rhynchophorus which produces as adult an electric organ discharge of very long duration (ca. 25 ms). We could indeed show (for the first time in a mormyrid fish) that the electric organ discharge which is first produced early during ontogeny in 33-mm-long juveniles is much shorter in duration and has a different shape than the electric organ discharge in 15-cm-long adults. The change from this juvenile electric organ discharges into the adult electric organ discharge takes at least a year. The increase in electric organ discharge duration could be causally linked to the development of surface evaginations, papillae, at the rostral face of the electrocyte which are recognizable for the first time in 65-mm-long juveniles and are most prominent at the periphery of the electrocyte.},
  language  = {en}
}
@misc{BleidornPodsiadlowskiZhongetal.2009,
  author    = {Bleidorn, Christoph and Podsiadlowski, Lars and Zhong, Min and Eeckhaut, Igor and Hartmann, Stefanie and Halanych, Kenneth M. and Tiedemann, Ralph},
  title     = {On the phylogenetic position of Myzostomida : can 77 genes get it wrong?},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-44893},
  year      = {2009},
  abstract  = {Background: Phylogenomic analyses recently became popular to address questions about deep metazoan phylogeny. Ribosomal proteins (RP) dominate many of these analyses or are, in some cases, the only genes included. Despite initial hopes, hylogenomic analyses including tens to hundreds of genes still fail to robustly place many bilaterian taxa. Results: Using the phylogenetic position of myzostomids as an example, we show that phylogenies derived from RP genes and mitochondrial genes produce incongruent results. Whereas the former support a position within a clade of platyzoan taxa, mitochondrial data recovers an annelid affinity, which is strongly supported by the gene order data and is congruent with morphology. Using hypothesis testing, our RP data significantly rejects the annelids affinity, whereas a platyzoan relationship is significantly rejected by the mitochondrial data. Conclusion: We conclude (i) that reliance of a set of markers belonging to a single class of macromolecular complexes might bias the analysis, and (ii) that concatenation of all available data might introduce conflicting signal into phylogenetic analyses. We therefore strongly recommend testing for data incongruence in phylogenomic analyses. Furthermore, judging all available data, we consider the annelid affinity hypothesis more plausible than a possible platyzoan affinity for myzostomids, and suspect long branch attraction is influencing the RP data. However, this hypothesis needs further confirmation by future analyses.},
  language  = {en}
}