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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Experience and mate choice in sailfin mollies (Poecilia latipinna)

Stewart, Audrey Julia 18 September 2014 (has links)
Learning and experience shape mate preferences in many species. My thesis investigates the role of experience on mating behavior of male and female sailfin mollies (Poecilia latipinna). In the first chapter I explore whether adult experience influences male sailfin molly mate preference for their sexual parasite, the Amazon molly (Poecilia formosa), and whether experience could account for reproductive character displacement (RCD) of male mate preference in this species. Sailfin males from sympatric populations show a stronger preference for conspecific females over Amazon mollies than do males from allopatric populations. I exposed males from sympatric and allopatric populations to either a sailfin female or an Amazon prior to a mating trial with an Amazon. For the allopatric population, males with recent experience with an Amazon directed fewer mating behaviors towards an Amazon during mating trials than did males with recent experience with a sailfin. Males from the sympatric population, however, performed the same amount of mating behaviors towards an Amazon regardless of experience. Thus adult experience influences mating preferences and suggests that experience may play a role in RCD in this species. In the second chapter I investigate whether a learned sensory bias could influence female mate preferences. Sensory biases that influence mate preferences can arise through selection on the sensory system in foraging and predator detection domains. I tested whether a learned preference originating outside of the mating domain, specifically a color-based food preference, can be transferred to a color-based preference for a male trait. I trained female sailfin mollies to associate either green or blue with food and then tested their preference for animated male sailfins featuring either a blue or green spot. I found that females did not prefer the male with the same color spot to which they had been conditioned. I discuss the problem of learned preference transfer and suggest directions for future research into the role of learning in sensory bias. / text
12

Hypervariable DNA markers and population structure in three fish species /

Laughlin, Thomas Fain, January 1993 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 109-117). Also available via the Internet.
13

Comparative Study of Dentition Among Species of Poecilia (Pisces)

Lewis, Steven R., Rasch, Ellen M., Hossler, Fred E., Kalbfleisch, John H., Monaco, Paul J. 01 January 1999 (has links)
Many studies in the genus Poecilia have focused on reproductive and genetic characteristics of Poecilia formosa, the Amazon molly, and its sympatric species P. latipinna and P. mexicana. The research literature of Poecilia dentition has been limited to general tooth morphology. Essentially absent are comparative analyses of dentition patterns and total numbers of teeth. The current study uses dentition analysis as a method to compare species in the genus Poecilia and to address some taxonomic issues related to these fish. The study focused on fish from the areas of southern Texas and northeastern Mexico. Through the use of scanning electron microscopy, the lower jaws of Poecilia spp were examined to determine total numbers of outer and inner teeth. In addition, the differences in distribution patterns of the inner teeth were recorded and compared. Statistical analyses were performed to determine which comparisons were significant. This study reveals several observations: 1) variations in the numbers of outer and inner teeth exist in some of these fish with respect to site of collection; 2) differences in total teeth numbers and dentition patterns were found both interspecifically and intraspecifically; and 3) in addition, dentition analysis provided evidence regarding the origin of P. formosa. This study supports the current notion that P. latipinna, the proported paternal component, and P. mexicana limantouri, the purported maternal component, are the progenitor species of P. formosa. Two unresolved taxonomic questions were addressed through dentition analysis. First, the present study supports the exclusion of the triploid associate of P. formosa as a separate species from P. formosa. Second, this study shows a significant difference in the number of inner teeth and in dentition patterns between P. mexicana limantouri and P. mexicana mexicana. Such differences, in addition to previously known distinguishing characteristics, should prompt careful consideration of whether or not these taxa deserve specific status or retention of their current subspecific status.
14

Cytogenetics of Bisexual/Unisexual Species of Poecilia. VI. Additional Nucleolus Organizer Region Chromosomal Clones of Poecilia Formosa (Amazon Molly) From Texas, With a Survey of Chromosomal Clones Detected in the Amazon Molly

Sola, Luciana, Galetti, Pedro M., Monaco, Paul J., Rasch, Ellen M. 01 January 1997 (has links)
This study reports the results of different staining techniques on the chromosomes of two Poecilia formosa lineages, providing evidence of two additional nucleolus organizer region (NOR) chromosomal clones in this gynogenetic fish. A comparative analysis of chromosomal clones detected in the Amazon molly, along with their frequency and distribution in different collecting sites, is also presented, and clonal heterogeneity resulting from chromosome changes is discussed.
15

Cytogenetics of Bisexual/Unisexual Species of Poecilia. IV. Sex Chromosomes, Sex Chromatin Composition and Ag-nor Polymorphisms in Poecilia Iatipinna: A Population From Mexico

Sola, Luciana, Bressanello, Simona, Rasch, Ellen M., Monaco, Paul J. 01 January 1993 (has links)
Cytogenetic analysis using C-banding, silver staining and fluorescent staining was carried out on a population sample of Poecilia Iatipinna derived from Tampico, Mexico, to verify the presence of sex chromosomes in individuals from the southern areas of this species range and to investigate the extent of C-band and Ag-NOR polymorphisms. Females were found to have W heteromorphic chromosomes, with large amounts of heterochromatin-rich in AT nucleotide sequences. C-banding corresponded to the pattern proposed as typical for the genus. Specimens share one of the Ag- NOR locations previously described in populations from the U.S.A. and show additional ones as well.
16

Proximátní kontrola pohlavního dimorfismu u živorodky Poecilia wingei / Proximate control of sexual dimorphism in livebearer Poecilia wingei

Farkačová, Klára January 2013 (has links)
The effect of 17α-methyltestosterone a 17β-estradiol on sex of livebearer fish Poecilia reticulata and P. wingei was studied. Solution of 2.5 mg testosterone was added in the aquarium the first and fifteenth day after delivery of new fry. Estrogen was administered in food to gravid females (400 mg per 1 kg food). Sex of all individuals was determined in one, two and three months. Administration of neither testosterone nor estrogen caused sex reversal; in the second case reproduction of almost all females was stopped.
17

Análise da variação molecular de Poecilia vivipara (Cypronodontiformes: Poecillidea) / Analysis of molecular variation of Poecilia vivipara (Cypronodontiformes: Poecillidea)

Tonhatti, Carlos Henrique, 1983- 21 August 2018 (has links)
Orientador: Sérgio Furtado dos Reis / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-21T03:14:37Z (GMT). No. of bitstreams: 1 Tonhatti_CarlosHenrique_M.pdf: 9319197 bytes, checksum: e71bff81e702fce4746841965b3022a1 (MD5) Previous issue date: 2012 / Resumo: Os poecilídeos são um excelente sistema modelo para estudos de evolução de história de vida seleção natural e sexual, evolução e coevolução experimental e evolução fenotípica em gradientes ecológicos. Os poecilídeos são também excelentes modelos para o estudo de processos ecológicos e evolutivos associados como a invasão e colonização de novos ambientes. As populações de Poecilia vivípara que ocorrem no sistema lagunar de Campos de Goytacazes no norte do estado do Rio de Janeiro são um exemplo notável de invasão e colonização de novos ambientes. Nesse sistema, a origem das lagoas deve-se a processos geomorfológicos associados com a formação do delta do rio Paraíba do Sul durante o Holoceno. Para este sistema formulamos a hipótese que a história geológica da região influenciou a variação genética atual em Poecilia vivípara. Deste modo, uma população de uma outra bacia hidrográfica seria diferente das populações da bacia do rio Paraíba do Sul. Uma população do rio Paraíba do Sul de uma região com formação mais antiga seria diferente das populações de regiões com história mais recente. Dentre as mais recentes as que vivem na área de influência marinha seriam diferentes das que vivem na área fluvial. A hipótese foi testada usando sequências da região de controle da replicação mitocondrial de 8 populações com 30 indivíduos cada. Os resultados mostraram uma grande diversidade genética dentro e entre as populações, estruturação genética entre as populações antigas recentes do rio Paraíba do Sul e que não houve mudanças no tamanho efetivo das populações recentemente. A partir dos resultados a hipótese formulada não foi refutada. Assim, existe relação entre a história geológica da região e a variação genética atual do P. vivípara. Há evidências que o regime de inundação característico da região também age sobre a variação genética destas populações aumentando o fluxo genético entre as mesmas / Abstract: The fishes of Poeciliidae family are an excellent model system for studies of life history evolution of natural and sexual selection, experimental evolution and coevolution in phenotypic evolution and ecological gradients. These are also excellent models for the study of ecological and evolutionary processes associated as the invasion and colonization of new environments. Populations of Poecilia vivipara occurring in the lagoon system of Goytacazes fields in northern Rio de Janeiro state are a notable example of invasion and colonization of new environments. In this system, the origin of the lakes due to geomorphological processes associated with the formation of the delta of the River Paraíba do Sul during the Holocene. For this system we hypothesized that the geological history of the region influenced the genetic variation present in Poecilia vivipara. Thus, a population of another watershed would be different populations of river basin Paraíba do Sul A population of Paraíba do Sul River in a region with older formation would be different regions with populations of more recent history. Among the most recent ones that live in the area of marine influence would be different from those who live in the river. The hypothesis was tested using sequences of the control region of mitochondrial replication of 8 populations with 30 individuals each. The results showed a high genetic diversity within and among populations, genetic structure among populations older times recent Paraíba do Sul river and that there were no changes in effective population size recently. From the results the hypothesis was not refuted. Thus, there is a relationship between the geological history of the region and genetic variation of the current P. vivipara. There is evidence that the flooding regime characteristic of the region also acts on the genetic variation of these populations increasing gene flow between them / Mestrado / Genetica Animal e Evolução / Mestre em Genética e Biologia Molecular
18

Brain size does not affect reproductive behaviour in male guppies (Poecilia reticulata)

Eckerström Liedholm, Simon January 2014 (has links)
The processes and mechanisms that govern brain size evolution remain a widely discussed topic in evolutionary biology. How relative brain size relates to animal behaviour and cognition is even more controversial. Recent comparative and experimental studies have shown a positive relationship between relative brain size and complexity of behaviour. Some of the most important behaviours that have direct consequences for an individual’s fitness are reproductive behaviours, and they sometimes require quite complex behavioural repertoires. Selection for complex behaviour might therefore induce an expansion of brain size to allow for cognitively demanding tasks during courtship and mating. In the present study we investigated the effect of relative brain size on reproductive behaviour in male guppies (Poecilia reticulata), using fish from a recently established brain size artificial selection experiment. Females were paired with either a large- or a small-brained male, and we collected data on a suite of male courtship behaviours including sneak copulation attempts, courtship display, gonopodial swings and time spent following the female. Although the extent of orange colouration, a trait that varies across large- and small-brained males, affected male behaviour, we were not able to detect any difference in reproductive behaviour between the brain size selection lines. These results suggest that there is no strong association between male mating behaviour and relative brain size, and future studies will examine this question further. But currently, our results indicate that relative brain size might not be linked to reproductive behaviour to any significant extent, at least not in the guppy.
19

ESTIMATIVA DOS PARÂMETROS GENÉTICOS DE CARACTERES MORFOMÉTRICOS EM GUPPY (Poecilia reticulata)

Gomide, Jefferson Mendes 17 December 2008 (has links)
Made available in DSpace on 2016-08-10T10:39:23Z (GMT). No. of bitstreams: 1 Jefferson Mendes Gomide.pdf: 1020338 bytes, checksum: 0191262649084f3b90170c5b28b340dd (MD5) Previous issue date: 2008-12-17 / The invasion of new environments is related to the genetic variability of the species. The guppy (Poecilia reticulata) is a species introduced accidentally or artificially, arisen from different populations of captivity around the world. In some countries, these introductions are made repeatedly, particularly to control the growth of disease-transmitting mosquitoes in small lakes and streams in tropical countries. The Guppy is feeding the larvae of mosquitoes, preventing it from coming into adult life. Because of the need to obtain a better understanding of the differentiation of introduced populations, and this may reduce the impact of the introduction of exotic species, since it is the third leading cause of extinction of native species, three populations in different cities of the state of Goias were collected, and their metric features analyzed. The review sought to determine the rate of divergence among populations of free life, which contribute to the understanding of the process of colonization of natural environments by this alien species. The results indicated that the divergence between the populations analyzed, for most of the features is very large, ie the rate of divergence is greater than expected by neutral evolution, so that directional selection is expected to be acting on these characteristics. / A invasão de novos ambientes se relaciona com a variabilidade genética das espécies. O Guppy (Poecilia reticulata) é uma destas espécies introduzidas acidentalmente ou artificialmente, advindo de várias populações de cativeiro em todo o mundo. Em alguns países, estas introduções se deram várias vezes, particularmente para o controle do crescimento de mosquitos transmissores de doenças, em lagos e pequenos riachos nos países tropicais. O Guppy se alimenta das larvas desses mosquitos, impedindo que cheguem à fase adulta. Devido à necessidade de se obter uma maior compreensão da diferenciação de populações introduzidas, e com isto poder reduzir o impacto da introdução de espécies exóticas, já que é a terceira causa de extinção de espécies nativas, foram coletadas três populações em cidades diferentes do estado de Goiás, e as suas características métricas analisadas. A análise procurou determinar a taxa de divergência, entre populações de vida livre, que contribuirá para a compreensão do processo de colonização dos ambientes naturais por esta espécie exótica. Os resultados indicaram que a divergência entre as populações analisadas, para a maioria das características é muito grande, ou seja, a taxa de divergência é maior do que a esperada pela evolução neutra, de modo que seleção direcional deve estar atuando sobre estas características.
20

Parâmetros comportamentais e reprodutivos para utilização como biomarcadores de desregulação endócrina em Poecilia vivipara

MELO, Laura Estela de 31 May 2016 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2017-05-03T15:52:19Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Laura - versão final - Corrigida_docx - sem assinatura.pdf: 1975245 bytes, checksum: 1380118f3f00203cdd14e785c8e7df92 (MD5) / Made available in DSpace on 2017-05-03T15:52:19Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação - Laura - versão final - Corrigida_docx - sem assinatura.pdf: 1975245 bytes, checksum: 1380118f3f00203cdd14e785c8e7df92 (MD5) Previous issue date: 2016-05-31 / CNPQ / Compostos desreguladores endócrinos (CDEs) contaminamecossistemas aquáticos esão capazes de imitar a ação de hormônios endógenos em peixes. Diante disso, este trabalho avaliouprimeiramente os efeitos da exposição de machos adultos de Poecilia viviparaa uma mistura ambiental de contaminantes com atividade estrogênica e ao CDE 17 α-etinilestradiol (EE2), envolvendo a análise química de moléculas estrogênicas na mistura ambiental, e de parâmetros bioquímicos, comportamentais e reprodutivos. Moléculas com atividade estrogênica foram quantificadas por cromatografia líquida com espectrometria de massas nas águasda Lagoa do Araçá (LA), do rio Capibaribe (RC) e no Complexo estuarino da Bacia do Pina (CEBP), região metropolitana de Recife. Machos adultos de P. vivipara cultivados em laboratório foram expostos por 14 dias a água limpa controle (EECT), ea 10ngEE2 L-1 (EE10) e 100 ngEE2 L-1 (EE100).Em paralelo, machos adultos residentes no CEBP foram coletados em LA, e trazidos ao laboratório. Machos expostos ao EE2 em laboratório e residentes no CEBP foram colocados em contato com fêmeas adultas cultivadas no laboratório, e os casais foram monitorados por um sistema de vídeo, com posterior avaliação quantitativa do comportamento sexual pelo software de análise comportamental Smart. Os parâmetros avaliados foram:número de contatos entre machos e fêmeas (NC); duração média dos contatos em segundos(YACUBIAN-FERNANDES et al.); distância média entre machos e fêmeas durante os contatos (DiC). O número de tentativas de cópula dos machos (TC) foi avaliado por observação humana dos vídeos, e a velocidade natatória dos machos isolados foi também quantificada pelo software Smart. Após a interação entre os casais, fêmeas pareadas com machos controle e LA foram mantidas isoladas em aquários por 90 dias para quantificação do sucesso de impregnação (SI) e do número de juvenis produzidos (NJP). Machos dos tratamentos EECT, EE10, EE100 e LA foram sacrificados e a quantidade de vitelogenina no fígado foi avaliada indiretamente por método histoquímico para coloração de fosfoproteínas. As análises cromatográficas indicaram a presença dos estrogênios estriol (E3), estrona (E1), EE2 e estradiol (E2), e de bisfenol A (BPA) nas concentrações médias de 31,8; 19,5; 11,9; 8,6; e 4,2 ng L-1, respectivamente, nas águas do CEBP, típicas de áreas urbanas contaminadas por esgotos domésticos. Machos expostos ao EE2 e provenientes da Lagoa do Araçá apresentaram indução de vitelogenina (p < 0,05). O número de contatos entre machos e fêmeas, e número de tentativas de cópula dos machos diminuiu nos casais em EE100 e LA (p < 0,05). A distância média entre machos e fêmeas durante os contatos aumentou em EE100 e LA (p < 0,05). Machos isolados expostos a EE10 e EE100 apresentaram hiperatividade natatória, enquanto machos provenientes de LA apresentaram hipoatividade natatória comparado aos controles. Machos de LA impregnaram 55% das fêmeas, enquanto machos controle impregnaram 88% das fêmeas. Fêmeas pareadas com machos controle (FeCt) produziram 7,1 juvenis em média, enquanto fêmeas pareadas com machos de LA (FeLA) produziram 2,7 juvenis (p = 0,019), totalizando 57 juvenis produzidos por FeCt versus 14 juvenis produzidos por FeLA, o que representa uma redução de 75% na geração de potenciais recrutas para a população. No segundo tema deste trabalho, machos e fêmeas adultos cultivados no laboratório foram mantidos isolados e ambos machos e fêmeas foram expostos por 30 dias ao herbicida atrazina nas concentrações 0 (controle-ATCT), 0,5μgL-1 (AT0,5); 5μgL-1 (AT5) e 50 μgL-1(AT50). Após a exposição, casais foram formados para cada tratamento, e o comportamento sexual foi analisado para o parâmetro TC por observador humano. A atividade natatória de machos e fêmeas mantidos isolados também foi avaliada. Após a exposição e pareamento dos casais, fêmeas de cada tratamento foram mantidas isoladas em aquários por 90 dias, para quantificação do número de ovócitos maduros (NO), e dos índices gonadossomático (IGS) e hepatossomático (Webb and Weihs). Os parâmetros NO, IGS e IHS para as fêmeas não foram alterados significativamente. Nos casais expostos a atrazina foi observada uma redução em TC na concentração de 5 (p > 0,05) e 50 μgL-1 (p < 0,05). Hiperatividade natatória foi detectada nas fêmeas expostas a todas concentrações, e em machos expostos a 5 (p > 0,05) e 50 μg L-1 (p < 0,05). Este estudo quantifica pela primeira vez CDEs estrogênicos em águas da região metropolitana de Recife, e demonstra o efeito de desreguladores endócrinos como o EE2 em laboratório, bem como os efeitos de uma mistura ambiental de contaminantes incluindo CDEs estrogênicos, em biomarcadores bioquímicos, comportamentais e reprodutivos de Poecilia vivipara, que podem afetar a viabilidade populacional em situações ambientalmente realistas. / Endocrine disruptor compounds (EDCs) contaminate aquatic ecosystems and are able to mimic the action of endogenous hormones in fish.Therefore, this study first evaluated the effects of adult male Poecilia vivipara exposure to an environmental mixture of contaminants with estrogenic activity and to the EDC 17 α-ethinylestradiol (EE2), involving the chemical analysis of estrogenic molecules in the environmental mixture, and biochemical, behavioral and reproductive parameters.Molecules with estrogenic activity were quantified by liquid chromatography with mass spectrometry in the waters of Lagoa do Araçá(LA) and the Capibaribe River (CR), in the Pina Basin estuarine complex (PBEC), metropolitan area of Recife. Laboratory grown adult male P. vivipara were exposed for 14 days to a clean water control (EECT) and to 10 ngEE2 L-1 (EE10) and 100 ngEE2 L-1 (EE100).In parallel, resident adult males in the PBEC were collected in LA, and brought to the laboratory.Males exposed to EE2 in the laboratory and residents of PBEC were placed in contact with adult females grown in the laboratory, and the couples were monitored by a video system, with subsequent quantitative assessment of sexual behavior by behavioral analysis software Smart.The parameters evaluated were: number of contacts between males and females (NC); average duration of contacts in seconds (YACUBIAN-FERNANDES et al.); average distance between males and females during the contacts (DiC). The number of male copulation attempts (Lichota et al.) was assessed by human observation of the videos, and swimming speed of single males was also quantified by the Smart software.After the interaction between couples, females paired with control and LA males were kept isolated in tanks for 90 days to quantify the impregnation success (IS) and the number of juveniles produced (NJP). Males of treatments EECT, EE10, EE100 and LA were sacrificed and the amount of vitellogenin in the liver was assessed indirectly by a histochemical staining method for phosphoproteins.Chromatographic analysis indicated the presence of estrogens estriol (E3), estrone (E1), EE2 and estradiol (E2), and bisphenol A (BPA) in concentrations averaging 31.8; 19.5; 11.9; 8.6; and 4.2 ng L-1, respectively, in PBEC waters, typical of urban areas contaminated by domestic sewage.Males exposed to EE2 and from Lagoa do Araçá showed vitellogenin induction (p <0.05).The number of contacts between males and females, and thenumber of male copulation attempts decreased in couples from EE100 and LA (p <0.05).The average distance between males and females during the contacts increased at EE100 and LA (p <0.05). Isolated males exposed to EE10 and EE100 developed swimming hyperactivity, while males from LA developed swimming hypoactivity compared to controls.LA males impregnated 55% of females, while control males impregnated 88% of females.Females paired with control males (FeCt) produced 7.1 juveniles on average, while females paired with LA males (FeLA) produced 2.7 juveniles (p = 0.019), totaling 57 juveniles produced by FeCt versus 14 juveniles produced by FeLA, which represents a 75% reduction in the generation of potential recruits for the population.In the second theme of this work, adult males and females grown in the laboratory were kept isolated and both males and females were exposed for 30 days to atrazine concentrations 0(control-ATCT), 0.5 μg L-1 (AT0.5); 5 μg L-1 (AT5) and 50 μg L-1 (AT50).After exposure, couples were formed for each treatment, and sexual behavior was analyzed for MCA by a human observer.Swimming activity of isolated males and females was also evaluated.After exposure and pairing of couples, females from each treatment were kept isolated in tanks for 90 days, to quantify the number of mature oocytes (NO), and the Gonadosomatic index (GSI) and hepatossomatic index (HSI). The parameters NO, GSI and HSI for females did not change significantly.In couples exposed to atrazine a significant reduction in MCA was observed at concentrations5 (p > 0,05) and 50 μg.L-1 (p <0.05). Hyperactive swimming was detected in females exposed to all concentrations, and in males exposed to 5 (p > 0.05) and 50 μgL-1 (p < 0.05).This study quantifies for the first time estrogenic EDCs in waters of the metropolitan area of Recife, and demonstrates the effect of endocrine disruptors such as EE2 in the laboratory, as well as the effects of an environmental mixture of contaminants including estrogenic EDCs, in biochemical, behavioral and reproductive biomarkers of Poecilia vivipara, which can affect population viability in environmentally realistic conditions.

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