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Felix Breden - One of the best experts on this subject based on the ideXlab platform.
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genomic organization of duplicated short wave sensitive and long wave sensitive opsin genes in the green swordtail xiphophorus helleri
BMC Evolutionary Biology, 2010Co-Authors: Corey T Watson, Krzysztof P Lubieniecki, Ellis R Loew, William S Davidson, Felix BredenAbstract:Background Long wave-sensitive (LWS) opsin genes have undergone multiple lineage-specific duplication events throughout the evolution of teleost fishes. LWS repertoire expansions in live-bearing fishes (family Poeciliidae) have equipped multiple species in this family with up to four LWS genes. Given that color vision, especially attraction to orange male coloration, is important to mate choice within poeciliids, LWS opsins have been proposed as candidate genes driving sexual selection in this family. To date the genomic organization of these genes has not been described in the family Poeciliidae, and little is known about the mechanisms regulating the expression of LWS opsins in any teleost.
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Molecular phylogeny of the live-bearing fish genus Poecilia (Cyprinodontiformes: Poeciliidae).
Molecular phylogenetics and evolution, 1999Co-Authors: Felix Breden, Margaret B. Ptacek, Michael Rashed, Donald C. Taphorn, Carlos A. FigueiredoAbstract:Members of the genus Poecilia exhibit extensive morphological, behavioral, and life history variation within and between species. This natural variation, coupled with short generation times and the ease with which members of this genus can be cultured in the lab, have made several species model systems for studying the effects of sexual and natural selection on the evolution of natural populations. Given that there is no clear understanding of the phylogenetic relationships within the genus, these studies have not been put into a historical context, and between-species comparisons have been limited. We sequenced the complete NADH Dehydrogenase Subunit 2 (ND2) mitochondrial gene (1047 bp) in representatives of the major divisions of the genus in order to examine these relationships. The subgeneric groups of Rosen and Bailey (1963) are, for the most part, supported, with some adjustment within the subgenera Poecilia and Pamphorichthys. The morphological distinctness of the groups within Poecilia suggest that the original generic designations be reinstated, but this awaits a more thorough analysis. Two implications from the phylogeny are particularly relevant to sexual selection studies: within the North and Central American mollies, the three species of sailfin mollies form a monophyletic group, and within the subgenus Lebistes, the sister taxon to the guppy, P. reticulata, is most likely the group of species previously designated as Micropoecilia.
Manfred Schartl - One of the best experts on this subject based on the ideXlab platform.
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the occurrence of spermatozoa in the ovary of the gynogenetic viviparous teleost poecilia formosa Poeciliidae
Journal of Morphology, 2016Co-Authors: Mari Carmen Uribe, Gabino De La Rosacruz, Harry J. Grier, Manfred SchartlAbstract:The reproductive mode of the female viviparous teleost Poecilia formosa (Poeciliidae) represents the phenomenon known as gynogenesis; that is, parthenogenetic development is initiated by spermatozoa which are needed for physiological activation of the egg and the initiation of gestation, but spermatozoa are prevented from contributing to the genome of the embryo. For the reason that no previous histological analyses of the ovary of this species during the reproductive cycle has been published the present study has been conducted. This study examined the histology of the ovary of P. formosa during nongestation and gestation phases and identified the presence of spermatozoa inside the ovary. Spermatozoa were observed in folds of the ovarian epithelium of P. formosa during both the nongestation and gestation phases. Sperm storage as documented in this study is a very important trait for the gynogenetic viviparous fish P. formosa contributing to the understanding of this species reproduction. J. Morphol. 277:341–350, 2016. © 2015 Wiley Periodicals, Inc.
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the occurrence of spermatozoa in the ovary of the gynogenetic viviparous teleost poecilia formosa Poeciliidae
Journal of Morphology, 2016Co-Authors: Mari Carmen Uribe, Gabino De La Rosacruz, Harry J. Grier, Manfred SchartlAbstract:The reproductive mode of the female viviparous teleost Poecilia formosa (Poeciliidae) represents the phenomenon known as gynogenesis; that is, parthenogenetic development is initiated by spermatozoa which are needed for physiological activation of the egg and the initiation of gestation, but spermatozoa are prevented from contributing to the genome of the embryo. For the reason that no previous histological analyses of the ovary of this species during the reproductive cycle has been published the present study has been conducted. This study examined the histology of the ovary of P. formosa during nongestation and gestation phases and identified the presence of spermatozoa inside the ovary. Spermatozoa were observed in folds of the ovarian epithelium of P. formosa during both the nongestation and gestation phases. Sperm storage as documented in this study is a very important trait for the gynogenetic viviparous fish P. formosa contributing to the understanding of this species reproduction.
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description of poecilia acanthophacelus obscura n sp teleostei Poeciliidae a new guppy species from western trinidad with remarks on p wingei and the status of the endler s guppy
Zootaxa, 2009Co-Authors: Susanne Schories, Manfred K Meyer, Manfred SchartlAbstract:Poecilia obscura, new species, is described from the Oropuche system, Trinidad. A mitochondrial DNA-sequence based molecular phylogenetic analysis revealed the status of the new species as a separate taxon. It is most closely related to the Common guppy, P. reticulata and to the recently described species, P. wingei. It can also be distinguished by morphometrics and gonopodial characteristics from these two species, although the ranges for all values overlap. A definition of the new species on morphology criteria alone is thus impossible. Therefore, P. obscura forms a cryptic species complex with the two other species. P. wingei is now unequivocally defined by the molecular phylogeny as a valid species. The three guppy species are included in the subgenus Acanthophacelus Eigenmann (1907), which is considered as generically different from all other taxa of the Poeciliinae sensu Parenti (1981).
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a haploid diploid triploid mosaic of the amazon molly poecilia formosa
Cytogenetic and Genome Research, 2007Co-Authors: Kathrin P Lampert, Claus Steinlein, Peter Fischer, M. Schmid, Manfred SchartlAbstract:We report the finding of the first haploid-diploid-triploid mosaic fish from the family Poeciliidae. The animal was derived from a laboratory cross of a female F1 hybrid of Poecilia mexicana&
Corey T Watson - One of the best experts on this subject based on the ideXlab platform.
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genomic organization of duplicated short wave sensitive and long wave sensitive opsin genes in the green swordtail xiphophorus helleri
BMC Evolutionary Biology, 2010Co-Authors: Corey T Watson, Krzysztof P Lubieniecki, Ellis R Loew, William S Davidson, Felix BredenAbstract:Background Long wave-sensitive (LWS) opsin genes have undergone multiple lineage-specific duplication events throughout the evolution of teleost fishes. LWS repertoire expansions in live-bearing fishes (family Poeciliidae) have equipped multiple species in this family with up to four LWS genes. Given that color vision, especially attraction to orange male coloration, is important to mate choice within poeciliids, LWS opsins have been proposed as candidate genes driving sexual selection in this family. To date the genomic organization of these genes has not been described in the family Poeciliidae, and little is known about the mechanisms regulating the expression of LWS opsins in any teleost.
David N. Reznick - One of the best experts on this subject based on the ideXlab platform.
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the origin and biogeographic diversification of fishes in the family Poeciliidae
PLOS ONE, 2017Co-Authors: David N. Reznick, Robert W. Meredith, Andrew I Furness, Mark S. SpringerAbstract:The fish subfamily Poeciliinae (sensu Parenti, 1981) is widely distributed across the Western Hemisphere and a dominant component of the fish communities of Central America. Poeciliids have figured prominently in previous studies on the roles of dispersal and vicariance in shaping current geographic distributions. Most recently, Hrbek et al. combined a DNA-based phylogeny of the family with geological models to provide a biogeographic perspective that emphasized the role of both vicariance and dispersal. Here we expand on that effort with a database enlarged in the quantity of sequence represented per species, in the number of species included, and in an enlarged and more balanced representation of the order Cyprinodontiformes. We combine a robust timetree based upon multiple fossil calibrations with enhanced biogeographic analyses that include ancestral area reconstructions to provide a detailed biogeographic history of this clade. Key features of our results are that the family originated in South America, but its major diversification dates to a later colonization of Central America. We also resolve additional colonizations among South, Central and North America and the Caribbean and consider how this reconstruction contributes to our understanding of the mechanisms of dispersal.
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comparative life histories of fishes in the subgenus limia pisces Poeciliidae
Journal of Fish Biology, 2015Co-Authors: S N Cohen, John U Regus, Y Reynoso, T Mastro, David N. ReznickAbstract:This study presents life-history descriptions for 12 species in the subgenus Limia, which are endemic to the Greater Antilles. All species in this study lack evidence of superfoetation, producing a single brood of offspring before developing subsequent broods. Interbrood intervals (number of days between parturition events) are also consistent with intervals of species that lack superfoetation. Maternal provisioning, characterized by matrotrophy index, is <1.0 for all species of Limia. This is consistent with species that provide little or no maternal provisioning to developing embryos after ovum fertilization (lecithotrophic). Four species exhibit potentially bi-modal size distributions of mature males. Work on other poeciliids suggests that such bimodal distributions can be caused by genetic polymorphisms in some species. Principle component analyses revealed an axis of interspecific variation in life histories that separated species with small size at maturity and the production of many, small offspring from those with large size at maturity and that produce few, large offspring. This pattern of life-history diversity occurs in many other groups of organisms.
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Molecular phylogenetic relationships and the coevolution of placentotrophy and superfetation in Poecilia (Poeciliidae: Cyprinodontiformes).
Molecular phylogenetics and evolution, 2011Co-Authors: Robert W. Meredith, David N. Reznick, Marcelo N. Pires, Mark S. SpringerAbstract:Members of Poeciliidae are used as model organisms for experimental studies on natural and sexual selection, and comparative studies of life-history evolution. The latter have demonstrated multiple origins of both superfetation and placentotrophy within Poeciliidae. Most recently, placentotrophy has been described in five species of Poecilia (Pamphorichthys), but only one of these (P. hasemani) shows evidence of superfetation. Here, we use a molecular phylogeny based on concatenated nuclear and mitochondrial gene sequences to test hypotheses of correlated evolution between superfetation and placentotrophy in Poecilia. Taxon sampling included all species in the subgenera Micropoecilia and Pamphorichthys for which the presence or absence of placentotrophy and superfetation have been determined, as well as representatives of all other Poecilia subgenera (Acanthophacelus, Limia, Mollienesia, Poecilia, Pseudolimia). Phylogenetic analyses were performed with maximum parsimony, maximum likelihood, and Bayesian methods; ancestral states for life-history characters were reconstructed with parsimony and SIMMAP; correlation analyses were performed with SIMMAP; and divergence times were estimated using a relaxed molecular clock. All subgenera in Poecilia were recovered as monophyletic. The basal split in Poecilia is between P. (Acanthophacelus )+ P .( Micropoecilia) and the other five subgenera. In the latter clade, P .( Poecilia) is the sister-group to the remaining four subgenera. Within P. (Pamphorichthys), all analyses with the combined data set recovered P. (Pamphorichthys) araguaiensis as the sister taxon to P .( Pamphorichthys) hollandi, and P .( Pamphorichthys) scalpridens as the sister taxon to P .( Pamphorichthys) minor. P .( Pamphorichthys) hasemani was either the sister taxon to P .( Pamphorichthys) hollandi + P .( Pamphorichthys) minor (maximum likelihood, Bayesian) or the sister taxon to all other Pamphorichthys species (maximum parsimony). Ancestral state reconstructions suggest that placentotrophy and superfetation evolved on the same branch in P .( Micropoecilia), whereas placentotrophy evolved before superfetation in P .( Pamphorichthys). SIMMAP analyses indicate a statistically significant association between placentotrophy and superfetation. Within P. (Micropoecilia) both placentotrophy and superfetation evolved in 64 million years. Within P .( Pamphorichthys), superfetation evolved in 69 million years on the P .( Pamphorichthys) hasemani branch, and placentotrophy evolved in 610 million years in the common ancestor of this subgenus.
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evolution of placentas in the fish family Poeciliidae an empirical study of macroevolution
Annual Review of Ecology Evolution and Systematics, 2009Co-Authors: B J A Pollux, Marcelo N. Pires, Amanda I Banet, David N. ReznickAbstract:The placenta is a complex organ that mediates all physiological and endocrine interactions between mother and developing embryos. Placentas have evolved throughout the animal kingdom, but little is known about how or why the placenta evolved. We review hypotheses about the evolution of placentation and examine empirical evidence in support for these hypotheses by drawing on insights from the fish family Poeciliidae. The placenta evolved multiple times within this family, and there is a remarkable diversity in its form and function among closely related species, thus providing us with ideal material for studying its evolution. Current hypotheses fall into two categories: adaptive hypotheses, which propose that the placenta evolved as an adaptation to environmental pressures, and conflict hypotheses, which posit that the placenta evolved as a result of antagonistic coevolution. These hypotheses are not mutually exclusive. Each may have played a role at different stages of the evolutionary process.
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independent evolution of complex life history adaptations in two families of fishes live bearing halfbeaks zenarchopteridae beloniformes and Poeciliidae cyprinodontiformes
Evolution, 2007Co-Authors: David N. Reznick, Robert W. Meredith, Bruce B ColletteAbstract:We have previously documented multiple, independent origins of placentas in the fish family Poeciliidae. Here we summarize similar analyses of fishes in the family Zenarchopteridae. This family includes three live-bearing genera. Earlier studies documented the presence of superfetation, or the ability to carry multiple litters of young in different stages of development in the same ovary, in some species in all three genera. There is also one earlier report of matrotrophy, or extensive postfertilization maternal provisioning, in two of these genera. We present detailed life-history data for approximately half of the species in all three genera and combine them with the best available phylogeny to make inferences about the pattern of life-history evolution within this family. Three species of Hemirhamphodon have superfetation but lack matrotrophy. Most species in Nomorhamphus and Dermogenys either lack superfetation and matrotrophy or have both superfetation and matrotrophy. Our phylogenetic analysis shows that matrotrophy may have evolved independently in each genus. In Dermogenys, matrotrophic species produce fewer, larger offspring than nonmatrotrophic species. In Nomorhamphus; matrotrophic species instead produce more and smaller offspring than lecithotrophic species. However, the matrotrophic species in both genera have significantly smaller masses of reproductive tissue relative to their body sizes. All aspects of these results are duplicated in the fish family Poeciliidae. We discuss the possible adaptive significance of matrotrophy in the light of these new results. The two families together present a remarkable opportunity to study the evolution of a complex trait because they contain multiple, independent origins of the trait that often include close relatives that vary in either the presence or absence of the matrotrophy or in the degree to which matrotrophy is developed. These are the raw materials that are required for either an analysis of the adaptive significance of the trait or for studies of the genetic mechanisms that underlie the evolution of the trait.
Robert C. Vrijenhoek - One of the best experts on this subject based on the ideXlab platform.
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Complete mitochondrial genome of the headwater livebearer, Poeciliopsis monacha: the mother of clones
Mitochondrial DNA. Part B Resources, 2016Co-Authors: Yeon Seon Jeon, Shannon B. Johnson, Yong-jin Won, Robert C. VrijenhoekAbstract:The sexually reproducing fish, Poeciliopsis monacha (Actinopterygii, Cyprinodontiformes, Poeciliidae), is the maternal ancestor of six hybrid biotypes that reproduce clonally. The gene content and order of its 16,818 bp mitochondrial genome is virtually identical with that of other sexually reproducing poeciliid fishes, providing no evidence for a mitochondrial involvement in the origins of all-female reproduction.
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HISTORICAL BIOGEOGRAPHY OF THE LIVEBEARING FISH GENUS POECILIOPSIS (Poeciliidae: CYPRINODONTIFORMES)
Evolution; international journal of organic evolution, 2002Co-Authors: Mariana Mateos, Oris I. Sanjur, Robert C. VrijenhoekAbstract:To assess the historical biogeography of freshwater topminnows in the genus Poeciliopsis, we examined sequence variation in two mitochondrial genes, cytochrome b (1140 bp) and NADH subunit 2 (1047 bp). This wide- spread fish genus is distributed from Arizona to western Colombia, and nearly half of its 21 named species have distributions that border on the geologically active Trans-Mexican Volcanic Belt (TMVB), a region that defines the uplifted plateau (Mesa Central) of Mexico. We used the parametric bootstrap method to test the hypothesis that a single vicariant event associated with the TMVB was responsible for divergence of taxa found to the north and south of this boundary. Because the single-event hypothesis was rejected as highly unlikely, we hypothesize that at least two geological events were responsible for divergence of these species. The first (8-16 million years ago) separated ancestral populations that were distributed across the present TMVB region. A second event (2.8-6.4 million years ago) was associated with northward dispersal and subsequent vicariance of two independent southern lineages across the TMVB. The geological history of this tectonically and volcanically active region is discussed and systematic implications for the genus are outlined.
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An ancient clonal lineage in the fish genus Poeciliopsis (Atheriniformes: Poeciliidae).
Proceedings of the National Academy of Sciences of the United States of America, 1992Co-Authors: Joseph M. Quattro, John C. Avise, Robert C. VrijenhoekAbstract:Genetic diversity in mtDNA was assessed within the unisexual (all female) hybridogenetic fish Poeciliopsis monacha-occidentalis and the two sexual species from which it arose. Results confirm that P. monacha was the maternal ancestor and that paternal leakage of P. occidentalis mtDNA has not occurred. Of particular interest is the high level of de novo mutational divergence within one hybridogenetic lineage that on the basis of independent zoogeographic considerations, protein electrophoretic data, and tissue grafting analysis is of monophyletic (single hybridization) origin. Using a conventional mtDNA clock calibration, we estimate that this unisexual clade might be >100,000 generations old. Contrary to conventional belief, this result shows that some unisexual vertebrate lineages can achieve a substantial evolutionary age.
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Molecular Evidence for Multiple Origins of Hybridogenetic Fish Clones (Poeciliidae: Poeciliopsis)
Genetics, 1991Co-Authors: Joseph M. Quattro, John C. Avise, Robert C. VrijenhoekAbstract:Hybrid matings between the sexual species Poeciliopsis monacha and Poeciliopsis lucida produced a series of diploid all-female lineages of P. monacha-lucida that inhabit the Rio Fuerte of northwestern Mexico. Restriction site analyses of mitochondrial DNA (mtDNA) clearly revealed that P. monacha was the maternal ancestor of these hybrids. The high level of mtDNA diversity in P. monacha was mirrored by similarly high levels in P. monacha-lucida; thus hybridizations giving rise to unisexual lineages have occurred many times. However, mtDNA variability among P. monacha-lucida lineages revealed a geographical component. Apparently the opportunity for the establishment of unisexual lineages varies among tributaries of the Rio Fuerte. We hypothesize that a dynamic complex of sexual and clonal fishes appear to participate in a feedback process that maintains genetic diversity in both the sexual and asexual components.
