@article{TiedemannMollPaulusetal.2005, author = {Tiedemann, Ralph and Moll, K. and Paulus, Kirsten B. and Schlupp, Ingo}, title = {New microsatellite loci confirm hybrid origin, parthenogenetic inheritance, and mitotic gene conversion in the gynogenetic Amazon molly (Poecilia formosa)}, issn = {1471-8278}, year = {2005}, abstract = {We describe the first microsatellite loci for the gynogenetic Amazon molly, Poecilia formosa, an all-female species arisen through hybridization of the bisexual species Poecilia mexicana and Poecilia latipinna. The loci showed one to six alleles and an expected heterozygosity between zero and 0.75. As expected with parthenogenetic inheritance, most loci were either constantly homozygous (five loci) or constantly heterozygous (eight loci). For six loci, both heterozygotes and homozygotes occurred. This and the fact that some loci only showed alleles of one of the ancestral species could indicate genome homogenization through mitotic gene conversion. Our new loci conformed to the hybrid origin of Amazon molly and are also applicable to both ancestral bisexual species}, language = {en} } @article{RieschSchluppTobleretal.2006, author = {Riesch, R{\"u}diger and Schlupp, Ingo and Tobler, Michael and Plath, Martin}, title = {Reduction of the association preference for conspecifics in cave-dwelling Atlantic mollies, Poecilia mexicana}, series = {Behavioral ecology and sociobiology}, volume = {60}, journal = {Behavioral ecology and sociobiology}, publisher = {Springer}, address = {New York}, issn = {0340-5443}, doi = {10.1007/s00265-006-0223-z}, pages = {794 -- 802}, year = {2006}, abstract = {Cave animals are widely recognised as model organisms to study regressive evolutionary processes like the reduction of eyes. In this paper, we report on the regressive evolution of species discrimination in the cave molly, Poecilia mexicana, which, unlike other cave fishes, still has functional eyes. This allowed us to examine the response to both visual and non-visual cues involved in species discrimination. When surface-dwelling females were given a chance to associate with either a conspecific or a swordtail (Xiphophorus hellerii) female, they strongly preferred the conspecific female both when multiple cues and when solely visual cues were available to the female. No association preference was observed when only non-visual cues were provided. In contrast, cave-dwelling females showed no preference under all testing conditions, suggesting that species recognition mechanisms have been reduced. We discuss the role of species discrimination in relation to habitat differences.}, language = {en} } @article{PlathSeggelBurmeisteretal.2006, author = {Plath, Martin and Seggel, Uta and Burmeister, Heike and Heubel, Katja U. and Schlupp, Ingo}, title = {Choosy males from the underground : male mating preferences in surface- and cave-dwelling Atlantic mollies (Poecilia mexicana)}, doi = {10.1007/s00114-005-0072-z}, year = {2006}, abstract = {Atlantic mollies (Poecilia mexicana) inhabit a variety of surface habitats, but they also occur in a sulfur cave in southern Mexico. We examined male mate choice relative to female body size in the cave population and in the most closely related surface-dwelling population from a nearby river. Males from both populations were either light- or dark-reared and could choose between two differently sized females either on the basis of visual cues in light or on the basis of solely nonvisual cues in darkness. Sexual preferences were estimated from the degree of association. Cave molly males always showed a preference for the larger female, both in light and in darkness. Among the surface males, only light-reared males showed a preference in the visual cues test, but not in darkness. In a control experiment, we demonstrated that male association preferences directly translate into actual mating preferences. Apparently, using visual cues for mate choice is the ancestral state in this system, and using nonvisual cues has evolved as a novel trait in the cave population. We discuss the evolution of nonvisual male mate choice in the context of changed environmental conditions, namely the absence of light, hypoxia, and toxic hydrogen sulfide in the cave}, language = {en} } @article{PlathRohdeSchroederetal.2006, author = {Plath, Martin and Rohde, Matthias and Schr{\"o}der, Thekla and Taebel-Hellwig, Angelika and Schlupp, Ingo}, title = {Female mating preferences in blind cave tetras Astyanax fasciatus (Characidae, Teleostei)}, issn = {0005-7959}, doi = {10.1163/156853906775133560}, year = {2006}, abstract = {The Mexican tetra Astyanax fasciatus has evolved a variety of more or less color- and eyeless cave populations. Here we examined the evolution of the female preference for large male body size within different populations of this species, either surface- or cave-dwelling. Given the choice between visual cues from a large and a small male, females from the surface form as well as females from an eyed cave form showed a strong preference for large males. When only non-visual cues were presented in darkness, the surface females did not prefer either males. Among the six cave populations studied, females of the eyed cave form and females of one of the five eyeless cave populations showed a preference for large males. Apparently, not all cave populations of Astyanax have evolved non-visual mating preferences. We discuss the role of selection by benefits of non-visual mate choice for the evolution of non-visual mating preferences}, language = {en} } @article{ToblerPlathBurmeisteretal.2006, author = {Tobler, Michael and Plath, Martin and Burmeister, Heike and Schlupp, Ingo}, title = {Black spots and female association preferences in a sexual / asexual mating complex (Poecilia, Poecilildae, Teleostei)}, doi = {10.1007/s00265-005-0152-2}, year = {2006}, abstract = {We investigated whether female association preferences for males are influenced by black spot disease (BSD), a parasite induced change of the host phenotype. We compared three different species of fish: a gynogenetic hybrid species, Poecilia formosa (amazon molly) and two sexual species (Poecilia latipinna and Poecilia mexicana), which were involved in the natural hybridisation leading to the amazon molly. Contrary to their sexual relatives, asexual amazon mollies significantly avoided images of males infected with black spot disease. We propose that amazon molly females have direct fitness benefits from choosing healthy males. The adaptive significance of the preference for BSD-uninfected males in the asexual amazon molly is yet unclear but may involve avoidance of predation or parasite infection as well as increased sperm availability}, language = {en} } @article{ToblerSchluppHeubeletal.2006, author = {Tobler, Michael and Schlupp, Ingo and Heubel, Katja U. and Riesch, Rudiger and Garcia de Leon, Francisco J. and Giere, Olav and Plath, Martin}, title = {Life on the edge: hydrogen sulfide and the fish communities of a Mexican cave and surrounding waters}, series = {Extremophiles : life under extreme conditions}, volume = {10}, journal = {Extremophiles : life under extreme conditions}, publisher = {Springer}, address = {Tokyo}, issn = {1431-0651}, doi = {10.1007/s00792-006-0531-2}, pages = {577 -- 585}, year = {2006}, abstract = {Most eucaryotic organisms classified as living in an extreme habitat are invertebrates. Here we report of a fish living in a Mexican cave (Cueva del Azufre) that is rich in highly toxic H2S. We compared the water chemistry and fish communities of the cave and several nearby surface streams. Our study revealed high concentrations of H2S in the cave and its outflow (El Azufre). The concentrations of H2S reach more than 300 mu M inside the cave, which are acutely toxic for most fishes. In both sulfidic habitats, the diversity of fishes was heavily reduced, and Poecilia mexicana was the dominant species indicating that the presence of H2S has an all-or-none effect, permitting only few species to survive in sulfidic habitats. Compared to habitats without H2S, P. mexicana from the cave and the outflow have a significantly lower body condition. Although there are microhabitats with varying concentrations of H2S within the cave, we could not find a higher fish density in areas with lower concentrations of H2S. We discuss that P. mexicana is one of the few extremophile vertebrates. Our study supports the idea that extreme habitats lead to an impoverished species diversity.}, language = {en} } @article{RieschToblerPlathetal.2009, author = {Riesch, R{\"u}diger and Tobler, Michael and Plath, Martin and Schlupp, Ingo}, title = {Offspring number in a livebearing fish (Poecilia mexicana, Poeciliidae) : reduced fecundity and reduced plasticity in a population of cave mollies}, issn = {0378-1909}, doi = {10.1007/s10641-008-9392-0}, year = {2009}, abstract = {Life history traits within species often vary among different habitats. We measured female fecundity in mollies (Poecilia mexicana) from a H2S-rich cave and from a neighbouring surface habitat, as well as in laboratory-reared individuals of both populations raised in either light or continuous darkness. Compared to conspecifics from surface habitats, cave-dwelling P. mexicana had reduced fecundity (adjusted for size) in the field. In the laboratory, the fecundity of surface mollies was higher in light than in darkness, whereas fecundity in the cave mollies was almost unaffected by the ambient light conditions. Our results suggest a heritable component to the reduction in fecundity in female cave mollies. Moreover, the reduced plasticity in fecundity of cave mollies in response to light conditions might be an example of genetic assimilation or channelling of a life history trait in a population invading a new environment.}, language = {en} } @misc{PlathHermannSchroederetal.2010, author = {Plath, Martin and Hermann, Bernd and Schr{\"o}der, Christine and Riesch, R{\"u}diger and Tobler, Michael and Garc{\´i}a de Le{\´o}n, Francisco J. and Schlupp, Ingo and Tiedemann, Ralph}, title = {Locally adapted fish populations maintain small-scale genetic differentiation despite perturbation by a catastrophic flood event}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-48599}, year = {2010}, abstract = {Background: Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre system in southern Mexico, where two strong environmental selection factors (darkness within caves and/or presence of toxic H2S in sulfidic springs) drive the diversification of P. mexicana. Nine nuclear microsatellites as well as heritable female life history traits (both as a proxy for quantitative genetics and for trait divergence) were used as markers to compare genetic differentiation, genetic diversity, and especially population mixing (immigration and emigration) before and after the flood. Results: Habitat type (i.e., non-sulfidic surface, sulfidic surface, or sulfidic cave), but not geographic distance was the major predictor of genetic differentiation. Before and after the flood, each habitat type harbored a genetically distinct population. Only a weak signal of individual dislocation among ecologically divergent habitat types was uncovered (with the exception of slightly increased dislocation from the Cueva del Azufre into the sulfidic creek, El Azufre). By contrast, several lines of evidence are indicative of increased flood-induced dislocation within the same habitat type, e.g., between different cave chambers of the Cueva del Azufre. Conclusions: The virtual absence of individual dislocation among ecologically different habitat types indicates strong natural selection against migrants. Thus, our current study exemplifies that ecological speciation in this and other systems, in which extreme environmental factors drive speciation, may be little affected by temporary perturbations, as adaptations to physico-chemical stressors may directly affect the survival probability in divergent habitat types.}, language = {en} } @article{McCoySyskaPlathetal.2011, author = {McCoy, Ellen and Syska, Norbert and Plath, Martin and Schlupp, Ingo and Riesch, R{\"u}diger}, title = {Mustached males in a tropical poeciliid fish - emerging female preference selects for a novel male trait}, series = {Behavioral ecology and sociobiology}, volume = {65}, journal = {Behavioral ecology and sociobiology}, number = {7}, publisher = {Springer}, address = {New York}, issn = {0340-5443}, doi = {10.1007/s00265-011-1154-x}, pages = {1437 -- 1445}, year = {2011}, abstract = {One possible mechanism for the (co-)evolution of seemingly novel male traits and female preferences for them is that males exploit pre-existing female biases, and livebearing fishes (Poeciliidae) have been at the forefront of this research for almost two decades. Here, using 13 poeciliid species from four different genera, we tested whether mustache-like rostral filaments found in males of some Mexican molly (Poecilia sphenops) populations could have evolved due to exploitation of a pre-existing female bias. While Mexican mollies were the only species with a significant female association preference for mustached males, we also did not find any species exhibiting significant aversion for mustached males; rather, variance in female preference scores was large throughout. For example, more than 25\% of females spent twice as much time with the mustached male compared to the non-mustached male in most species, but even 31\% of Mexican molly females spent more time near the non-mustached male. Hence, a comparison of the strength of preference was inconclusive. We discuss the possibility that the female preference of P. sphenops for mustached males could be due to a female pre-existing bias (sensu lato), even if population means were not significant for species other than P. sphenops. This highlights the importance of distinguishing between population means and individual preferences when interpreting mate choice, and thus, adds depth to the concept of mating preferences as a motor for evolutionary change.}, language = {en} } @misc{SchedinaHartmannGrothetal.2014, author = {Schedina, Ina Maria and Hartmann, Stefanie and Groth, Detlef and Schlupp, Ingo and Tiedemann, Ralph}, title = {Comparative analysis of the gonadal transcriptomes of the all-female species Poecilia formosa and its maternal ancestor Poecilia mexicana}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-401420}, pages = {10}, year = {2014}, abstract = {Background The Amazon molly, Poecilia formosa (Teleostei: Poeciliinae) is an unisexual, all-female species. It evolved through the hybridisation of two closely related sexual species and exhibits clonal reproduction by sperm dependent parthenogenesis (or gynogenesis) where the sperm of a parental species is only used to activate embryogenesis of the apomictic, diploid eggs but does not contribute genetic material to the offspring. Here we provide and describe the first de novo assembled transcriptome of the Amazon molly in comparison with its maternal ancestor, the Atlantic molly Poecilia mexicana. The transcriptome data were produced through sequencing of single end libraries (100 bp) with the Illumina sequencing technique. Results 83,504,382 reads for the Amazon molly and 81,625,840 for the Atlantic molly were assembled into 127,283 and 78,961 contigs for the Amazon molly and the Atlantic molly, respectively. 63\% resp. 57\% of the contigs could be annotated with gene ontology terms after sequence similarity comparisons. Furthermore, we were able to identify genes normally involved in reproduction and especially in meiosis also in the transcriptome dataset of the apomictic reproducing Amazon molly. Conclusions We assembled and annotated the transcriptome of a non-model organism, the Amazon molly, without a reference genome (de novo). The obtained dataset is a fundamental resource for future research in functional and expression analysis. Also, the presence of 30 meiosis-specific genes within a species where no meiosis is known to take place is remarkable and raises new questions for future research.}, language = {en} }