This thesis attempts to improve our understanding of the role of population size for the process of speciation. First, the effect of population size on speciation is studied using several meta-analyses of published laboratory experiments. Second, the effect of population size on behaviour is studied using a laboratory population of the blowfly Lucilia sericata. Third, the effect of population size on morphological and genetic variation is studied using wings and microsatellites from wild populations of L. illustris as well as experimentally bottlenecked populations of L. sericata. The meta-analyses showed that the result of many previous laboratory experiments on sympatric and parapatric speciation may have been biased by too small population sizes. Reduced interbreeding was less likely to develop in small populations where the selection against hybridisation often seemed to have been opposed by inbreeding depression or loss of genetic variation. In allopatric speciation experiments, no general consistent effect of population size was observed. There was no support for speciation through founder events. In fact, significant assortative mating was only found in vicariance experiments where derived populations was tested against each other. Population size influenced reproductive behaviour in L. sericata. There was a positive effect of increasing number of males on egg-laying but only as long as the female was in the company of at least one other female. Female mate choice and a positive effect of number of eggs on larval survival are suggested to be the underlying factors. No historic bottlenecks could be detected in the fly populations, but strong genetic indications suggest a fine grained genetic population structure of wild Lucilia flies. Bottlenecks had unpredictable effects on wing morphology as well as on genetic variation and fitness in a laboratory stock of L. sericata. Thus a bottlenecked population will not necessarily have a higher chance of evolving morphological novelties than one which has not undergone a bottleneck. However, among many bottlenecked populations there is a good chance that in at least one of them the conditions will be conducive to morphological change and evolution. In this statistical sense, thus, strong population fluctuations may enhance the probability of speciation events.

<p>Koi and goldfish have been released into rivers in South Africa since the 1800&rsquo / s for food and sport fish and have since spread extensively. These fish are present in most of the river systems in South Africa and pose an additional threat the indigenous cyprinids in the Western Cape. Monogenean parasites of the genus Gyrodactylus are of particular concern, as their unique biology renders them a possible threat. Gyrodactylus kherulensis and G. kobayashii were identified from koi and goldfish respectively imported from Asia, Europe and locally bred fish. Morphometrics and the use of statistical classifiers, which includes univariate (ANOVA and Kruskal-Wallis), bivariate (Pearson&rsquo / s correlation) and multivariate (Principal Component Analysis) placed the two species within their respective groups. There was some intraspecific variation among the different populations collected from the various locations, especially in the hamulus and ventral bar features, but the marginal hooklets, however, remained static for both helminth species.</p>

Made available in DSpace on 2016-06-02T19:32:13Z (GMT). No. of bitstreams: 1 6480.pdf: 1713092 bytes, checksum: 7682b21d5ab678d6b42870e1ac14451b (MD5) Previous issue date: 2014-10-27 / Universidade Federal de Sao Carlos / Physalaemus is the largest genus, with regard to number of species, of the subfamily Leiuperinae, the taxonomy of which has been the subject of recent studies due to the high intraspecific and low interspecific variation within the group, with patterns of variation possibly related to geographic distribution. The Physalaemus albifrons species was first collected by Johann Baptiste von Spix in 1824, and its type locality is the "Province of Bahia", even though it is distributed from Maranhão to Minas Gerais, in regions characterized by the Caatinga morphoclimatic zone in areas of transition with the Cerrado. Due to the variation in the dorsal pattern found in Physalaemus albifrons, authors have put foward the hypothesis of the species being included in a species complex, meaning there would be more species registered under a single common name. Based on this, 98 individuals were studied, associated with each sampled location by means of analysis of morphological and morphometric characters, thus redescribing the species. Physalaemus albifrons presents four intrapopulational dorsal coloration patterns, varying from homogeneously spotless; longitudinal and irregular linear dark spots; as well as dark spots in an omega-like pattern. The second tubercle next to the tibiotarsal articulation, the absence of inguinal glands and the snout-vent length from 18,1 mm to 33,8mm proved to be diagnostic features in order to differentiate Physalaemus.albifrons from other species of the genus. This species, which may also be described as being average-sized for this genus, with the head greater in width than in length; and the snout subelliptical in dorsal view. The populations presents morphological variation as to the distinction of the tympanic ring which might be visible in some individuals and indistinguishable in others, leading to the definition of two morphological groups which are unified through canonical discriminant analysis, therefore discarding the possible characterization of the species complex in Physalaemus albifrons. / Physalaemus é o maior gênero em número de espécies da subfamília Leiuperinae, cuja taxonomia tem sido alvo de recentes estudos devido à elevada variação intraespecífica e baixa variação interespecífica apresentada pelo grupo, com padrões de variação possivelmente relacionados com a distribuição geográfica. A espécie Physalaemus albifrons foi coletada pela primeira vez por Johann Baptiste von Spix em 1824 e a localidade tipo registrada é Província da Bahia , contudo está distribuída desde o Maranhão até Minas Gerais, em regiões caracterizadas pelo domínio morfoclimático da Caatinga em áreas de transição com o Cerrado. Devido à variação no padrão de desenhos dorsais apresentada por Physalaemus albifrons, autores levantam a hipótese de a espécie estar incluída em um complexo de espécies, ou seja, haveriam mais espécies registradas sob um mesmo nome. Baseando-se nisto, 98 exemplares foram estudados, associados a cada localidade amostrada, analisando-se caracteres morfológicos e morfométricos, redescrevendo-se a espécie. Physalaemus albifrons apresenta quatro padrões intrapopulacionais de coloração dorsal, variando de homogêneo sem manchas, com manchas escuras lineares longitudinais e irregulares e também com manchas escuras em padrão de ômega. O segundo tubérculo presente próximo da articulação tíbio-tarsal, a ausência de glândulas inguinais e o comprimento rostro cloacal de 18,1-33,8 mm se mostraram características diagnósticas para diferenciar Physalaemus albifrons das demais espécies do gênero. Esta espécie, podendo ainda ser descrita como de tamanho médio para este gênero, com a cabeça mais larga do que longa e o focinho subelíptico em vista dorsal. As populações apresentam variação morfológica quanto à distinção do aro timpânico, que pode ser visível em alguns exemplares e indistinguível em outros, definindo-se dois grupos morfológicos unificados através da análise de discriminante canônica, descartando-se, assim, a possibilidade de caracterização do complexo de espécies em Physalaemus albifrons.

Submitted by ANA CLÁUDIA DOS SANTOS null (anaclaudiad.santos@hotmail.com) on 2016-03-30T17:38:39Z No. of bitstreams: 1 Dissertacao_Mestrado_AnaClaudiaSantos.pdf: 5092134 bytes, checksum: 740b61e0123f1febd03568f1a8de8971 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-01T13:43:21Z (GMT) No. of bitstreams: 1 santos_ac_me_sjrp.pdf: 5092134 bytes, checksum: 740b61e0123f1febd03568f1a8de8971 (MD5) / Made available in DSpace on 2016-04-01T13:43:21Z (GMT). No. of bitstreams: 1 santos_ac_me_sjrp.pdf: 5092134 bytes, checksum: 740b61e0123f1febd03568f1a8de8971 (MD5) Previous issue date: 2016-02-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A sistemática de Piabina Reinhardt, 1867 tem sido questionada recentemente. Espécies novas e possíveis sinônimos (e.g., Astyanax paranahybae) foram sugeridos para o gênero e a espécie-tipo, Piabina argentea, foi considerada recentemente um complexo de espécies. Diante dessas hipóteses realizamos uma revisão sistemática, incluindo análises taxonômica, filogenética e discriminante, compreendendo as espécies válidas e as supostamente novas (Capítulo I). Foi possível reconhecer quatro morfotipos intraespecíficos com base em caracteres morfológicos [Piabina argentea sensu stricto, Piabina sp. A (sensu Cardoso), Piabina sp. ‘nordeste’ e Piabina sp. ‘tiete’]. No entanto, observou-se elevada sobreposição nos caracteres morfológicos entre os morfotipos, corroborado pela análise discriminante (DAPC). Caracteres filogenéticos homoplásticos foram recobrados para as espécies e morfotipos de Piabina, encontrados em politomia no gênero. A sobreposição de caracteres morfológicos e a ausência de caracteres filogenéticos robustos às espécies e aos morfotipos impossibilitam o reconhecimento inequívoco destes como unidades biológicas distintas. Assim, Piabina é considerada um gênero monotípico, com P. anhembi e Astyanax paranahybae como sinônimos juniores de P. argentea. Piabina argentea é semelhante a outros Stevardiinae, principalmente algumas espécies de Bryconamericus e Creagrutus. Equívocos na identificação da espécie em coleções científicas motivaram a elaboração de uma chave para identificação de Stevardiinae da bacia do alto rio Paraná. A chave, que inclui 15 espécies de estevardiíneos, é uma ferramenta útil à identificação correta das espécies, especialmente as relacionadas filogeneticamente à P. argentea (Capítulo II). / Recently, the systematic of Piabina Reinhardt, 1867 has been questioned. New species and possible synonyms (e.g., Astyanax paranahybae) were suggested to the genus and the type species, Piabina argentea, was recently considered as a complex of different species. In view of these new hypothesis, we performed a systematic review with taxonomic, phylogenetic, and discriminant data, including all valid species and the species reported as new of Piabina (Chapter I). We identified four intraspecific morphotypes based on morphological characters [Piabina argentea sensu stricto, Piabina sp. A (sensu Cardoso), Piabina sp. ‘nordeste’ e Piabina sp. ‘tiete’]. However, it was observed a significant overlapping of taxonomic characters among the morphotypes, posteriorly corroborated by the discriminant analysis (DAPC). We found homoplastics phylogenetic characters to species and morphotypes of Piabina, arranged in politomy in the genus. The overlapping of morphological characters and the lack of robust phylogenetic characters do not allow us to recognize these taxa as distinct biological units. Thus, Piabina was considered a monotipic genus, with P. anhembi and Astyanax paranahybae as junior synonyms of P. argentea. Piabina argentea is similar to other species of Stevardiinae, mainly some Bryconamericus and Creagrutus species. Mistakes in Piabina identification observed in scientific collections motivated the elaboration of an identification key to the Stevardiinae from the upper Paraná River basin. The key included 15 Stevardiinae species and represents a helpful tool to identify species correctly, especially the species phylogenetic related to P. argentea (Chapter II).

Orientador: Louis Bernard Klaczko / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T02:56:34Z (GMT). No. of bitstreams: 1 Silva_LauraHelenaHafnerda_M.pdf: 2141945 bytes, checksum: 17c00d0d744de62b04cc274305caedb5 (MD5) Previous issue date: 2006 / Resumo: O presente trabalho tem como objetivo caracterizar a variação do tamanho e forma das asas de populações de Drosophila melanogaster em três pontos ao longo de uma grande amplitude latitudinal na costa brasileira. O trabalho foi feito a partir de coletas realizadas no Recife, Rio de Janeiro e Porto Alegre, e os seguintes aspectos foram abordados: 1) variação geográfica; 2) variação temporal; 3) herdabilidade; e 4) a influência de inversões cromossômicas. Para este fim, o método da elipse foi aplicado a imagens digitalizadas das asas, e foram analisados: o tamanho das asas, sua forma e as posições dos pontos de junção e das extremidades das veias (caracterizadas por suas coordenadas angulares é radiais, essas padronizadas pelo tamanho da asa). Os resultados obtidos mostraram que a variação de tamanho em D. melanogaster no Brasil segue a tendência mundial de formação de clines latitudinais, com indiv.íduos maiores sendo encontrados a latitudes também maiores. No entanto, a herdabilidade e a variação temporal entre múltiplas coletas realizadas no Recife e no Rio de Janeiro não apresentou um padrão regular nítido. O único efeito consistente e significativo de inversões cromossômicas que pudemos observar foi o de In(3R)Payne sobre o tamanho corporal, sendo também consistente com achados prévios descritos na literatura. Entretanto, não detectamos efeito significativo de interação genótipo-ambiente, quer entre coletas, quer entre localidades / Abstract: The present work aims to characterize the variation of wing size and shape in Drosophila melanogaster populations from three localities distributed along a wide latitudinal range of the Brazilian coast. The work was performed based on collections made in the cities of Recife, Rio de Janeiro and Porto Alegre. The aspects studied were: 1) geographic variation; 2) temporal variation; 3) heritability; and 4) the influence of chromosomal inversions. To this end, the ellipse method was applied to digitized images of the wings. We analyzed wing size, wing shape and the position of vein junctions and extremities (characterized by their angular and radial coordinates, the latter being standardized by wing size). The results obtained showed that size variatiorn in Brazilian D. melanogaster follows the worldwide tendency toward the formation of latitudinal clines, with larger individuaJs being found at higher latitudes. However, the heritability and temporal variation among multiple collections performed in Recife and Rio de Janeiro did not show a clear regular pattern. The only consistent and significant effect of chromosomal inversions that we could observe was that of In(3R)Payne on body size, which is also consistent with previous findings reported in the literature. However, we did not detect a significant effect of genotype-environment interactions, neither among collections, nor among localities / Mestrado / Genetica Animal e Evolução / Mestre em Genética e Biologia Molecular

Magister Scientiae (Biodiversity and Conservation Biology) / The expansion of the South African aquaculture industry coupled with the lack of effective parasite management strategies may potentially have negative effects on both the freshwater biodiversity and economics of the aquaculture sector. Koi and goldfish are notorious for the propagation of parasites worldwide, some of which have already infected indigenous fish in South Africa. Koi and goldfish have been released into rivers in South Africa since the 1800’s for food and sport fish and have since spread extensively. These fish are present in most of the river systems in South Africa and pose an additional threat the indigenous cyprinids in the Western Cape. Monogenean parasites of the genus Gyrodactylus are of particular concern, as their unique biology renders them a possible threat. Gyrodactylus kherulensis and G. kobayashii were identified from koi and goldfish respectively imported from Asia, Europe and locally bred fish. Morphometrics and the use of statistical classifiers, which includes univariate (ANOVA and Kruskal-Wallis), bivariate (Pearson’s correlation) and multivariate (Principal Component Analysis) placed the two species within their respective groups. There was some intraspecific variation among the different populations collected from the various locations, especially in the hamulus and ventral bar features, but the marginal hooklets, however, remained static for both helminth species. This illustrates again the importance of the minor variations in the marginal hook features in gyrodactylid taxonomy. Infection trials conducted by co-habitation of infected koi and goldfish with two indigenous redfin minnow species, Pseudobarbus burchelli and P. phlegethon showed that both G. kherulensis and G. kobayashii could successfully transfer and establish themselves on P. phlegethon, where the infection increased rapidly initially, but remained relatively constant thereafter. P. burchelli appeared to be inherently resistant as the parasite population growth rate initially remained steady, until the infection died off. The wild-caught indigenous fish were however not infected with any exotic Gyrodactylus species, but a new species, G. burchelli n. sp. described from the body surfaces of P. burchelli. / South Africa

京都大学 / 新制・課程博士 / 博士(工学) / 甲第23514号 / 工博第4926号 / 新制||工||1769(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 安部 武志, 教授 作花 哲夫, 教授 阿部 竜 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Molecular and morphologic studies were used to determine the evolution, classification and differentiation of Nymphaea odorata. Molecular analyses of the nuclear internal transcribed spacer (ITS) region, the chloroplast trnL-F region, and inter-simple sequence repeat (ISSR) markers determined the variation present between and within two species of Nymphaea. The ITS region resulted in a phylogeny depicting strong separation between species (N. mexicana and N. odorata) and some separation between N. odorata's subspecies. The ITS region contained polymorphisms, which upon SAHN clustering and principle coordinate (PCOA) and minimum spanning tree (MST) analyses produced groups similar to the clades in the ITS phylogeny. Sixteen accessions were chosen for trnL-F analysis, where a subspecies-specific molecular marker was found. In most accessions the marker confirmed the original subspecies classification. Molecular analyses using ISSRs characterized among population variation in N. odorata and N. mexicana using five primers. ISSR markers among populations were highly variable within a species and were used in UPGMA, PCOA and MST analysis, which resulted in separation between the subspecies. Both univariate and multivariate analyses were performed on quantitative and qualitative morphological characters. An analysis of variance resulted in six morphological characteristics that were statistically significant (P< 0.05), the majority being leaf blade characteristics. Multivariate statistics of principle component analysis and discriminate analysis resulted in groups for each subspecies, both emphasized the importance of quantitative leaf blade characteristics. Overall, both morphology and molecular characteristics supported the classification of subspecies for ssp. odorata and ssp. tuberosa, due a lack of strong segregation of characteristics. / Master of Science

Capsella bursa-pastoris (L.) Medik. is a species with a cosmopolitan distribution which shows considerable morphological variation. Numerous authors have recognised widely differing numbers of varieties, microspecies or other infraspecific subdivisions (segregates) of this species. In an attempt to clarify this situation, we grew British material of the species under controlled conditions through to the F) generation to remove environmental variation, and assessed the plants on the basis of a range of morphological criteria, namely leaf shape, capsule size and also length of time taken to flower. Analysis of these characteristics consistently produced four basic groups, which had been previously described. Herbarium specimens could also nearly always be assigned to one of these groups. Limited chromosome counts suggest that two of these groups are diploid and two are tetraploid. We suggest this fourfold division into broad groups reflects the major genetic separations within the species, but that there is also considerable phenotypic plasticity shown by C. bursapastoris in response to factors such as shade or trampling. These four groups appear to differ in their geographic.al distribution in Britain. KEYWORDS: Shepherd's Purse, morphological variation, leaf characters, capsule characters, chromosome

京都大学 / 新制・課程博士 / 博士(エネルギー科学) / 甲第24713号 / エネ博第456号 / 新制||エネ||85(附属図書館) / 京都大学大学院エネルギー科学研究科エネルギー基礎科学専攻 / (主査)教授 野平 俊之, 教授 萩原 理加, 教授 佐川 尚 / 学位規則第4条第1項該当 / Doctor of Energy Science / Kyoto University / DFAM