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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.
231

Partnerwahl, Sexualdimorphismus & Populationsunterschiede in Chorthippus biguttulus / (Orthoptera, Acrididae)

Stange, Nicole 27 February 2012 (has links)
Die Heuschreckenart Chorthippus biguttulus (Orthoptera: Acrididae) ist ein Modellorganismus für akustische Kommunikation. Die Männchen stridulieren durch Reiben des Hinterbeins gegen eine Flügelvene. Diese Dieser Gesang bietet Weibchen Informationen über Artzugehörigkeit, Geschlecht und u.U. die Qualität. Rezeptive Weibchen antworten auf arteigene und attraktive Gesänge. Ich untersuchte, welche Informationen der Männchengesang enthält, wie diese sich in Gesangsparametern manifestieren und welche Informationen rezipiert werden. Ich untersuchte Abhängigkeiten zwischen Gesang und Temperatur, Alter, Morphologie und Immunkompetenz. Ebenfalls testete ich auf eine Infektion mit Wolbachia sp.. Mit Playback-Versuchen wurde die Präferenz der Weibchen getestet. Der Sexualdimorphismus, Populationsunterschiede und Unterschiede zwischen Freiland- und F1-Populationen wurden untersucht. Es konnte gezeigt werden, dass die Männchengesänge in geringem Maße altersabhängig waren während sie Temperatur den Gesang stark beeinflusst. Länger andauernde Nymphenphasen induzierten veränderte Gesangsmerkmale. Größere und schwerere Beine korrelierten mit dem Onsetsowie der Versdauer und der Pausendauer. Die Phasenverschiebung der Hinterbeine hing stark mit der Störpausentiefe und der Thoraxbreite zusammen. Die Werte der Immunkompetenz korrelierten positiv mit dem Onset des Gesangs des jeweiligen Männchens sowie der Femurlänge. Die Weibchen bevorzugten Männchengesänge, die tiefe Offsets, lange Periode, bzw. Silben, geringe Störpausen und besonders lange Versdauern aufwiesen. Die Tiere zeigten einen hohen Grad an Sexualdimorphismus in Morphologie und Gesang. Ebenfalls waren starke Unterschiede in fast allen untersuchten Morphologiemerkmalen und den meisten Gesangsparametern verschiedener Populationen von Männchen festzustellen, wobei die Weibchenpräferenzen ähnlich waren und der artspezifische Parameter, das Silben-Pausen-Verhältnis, sich nicht unterschied. / The grasshopper Chorthippus biguttulus (Orthoptera: Acrididae) is a model organism for acoustic communication. The males stridulate by rubbing the hind legs against their forewings. The "song" is species-specific and contains information about the gender and perhaps about the quality. Receptive females answer by singing, if the male song is attractive. I worked on the question, which information about the male is in the song, which song parameters contain the information and which of these information is received by the females. I tested correlations between the song parameters and temperature, age, morphology and immunocompetence and I tested for an infection with Wolbachia sp.. The females’ preferences on male songs were tested with playback-experiments. I investigated the sexual size dimorphism and behavioral differences and the differences in these parameters of animals of different sites in Germany and of laboratory and field animals. The male songs were on a small scale age-dependent. Temporal parameters) depended very much from the temperature and decrease with higher temperatures. The developmental time correlated with the duration of the syllables, the onset variances and the gaps in the syllable. Males with longer and heavier legs produced higher onset, longer verses and longer pauses. The gaps in the syllable amplitude and the width of the thorax correlated with the phase shifting of the hind legs. The immunocompetence rate was positively correlated with the onset and the length of the femur. Females preferred male songs, which contained deep offsets, long periods (syllables), small gaps and long verse durations. The species showed a high degree on sexual dimorphism in morphology and the song parameters. The animals of different populations differed significantly in almost every morphology parameter and a lot of song parameters, while the syllable-to-pause-ration (species-specific) was constant. The females preference of the different sites were similar.
232

Sexual selection in Drosophila simulans

Sharma, Manmohan Dev January 2010 (has links)
Over the last 100 years sexual selection has advanced into a vast field of theoretical and empirical research. While Darwin’s idea of female preference being an integral mechanism of sexual selection is no longer debated, our understanding of female preference is still very limited. For example, we know little about the genetic variation in female preference, and the costs of preference over and above the costs of mating with particular male phenotypes. Additionally, while costs of mate choice are well documented, the benefits of mate choice and their implications are still debated. For example, controversy exists over the inevitability of good gene benefits and their capability to promote adaptive sexual selection. Furthermore, the adaptiveness of sexual selection itself is debated. Our understanding of the traits involved in mate choice is also far from complete. Here I investigated aspects of sexual selection in Drosophila simulans, employing a range of behavioural approaches along with artificial selection and environmental manipulations. The findings presented here indicate that female preference can evolve when directly selected on, and that preference itself is not particularly costly. There was also no conclusive evidence for the good genes benefits of mate choice in D. simulans. These benefits are considered crucial in promoting the adaptiveness of sexual selection, and although we found sexual selection to be adaptive under some test conditions it was not adaptive in other conditions. Our investigations into traits involved in mate choice established sex-specific genetic variation in cuticular hydrocarbons and the genetic architecture of this trait was found to sex-specific evolution of cuticular hydrocarbons under natural and sexual selection. Additionally, we found that a secondary sexual character, the sex combs was positively allometric – just like most signalling and weapon traits, and there was no association between trait fluctuating asymmetry and trait size. These findings collectively indicate that sexual selection in D. simulans is consistent with classical models of this process.
233

Morcego hematófago comum Desmodus rotundus no Vale do Paraíba, Estado de São Paulo: abrigos diurnos, agrupamentos, lesões corporais e sorologia antirrábica / The common hematophagous bat Desmodus rotundus in the Paraíba Valley, State of São Paulo: diurnal shelters, groups, body injuries and rabies sorology

Ferrari, João José de Freitas 30 April 2015 (has links)
Apesar dos morcegos hematófagos serem muito estudados, diversos aspectos de sua biologia e de seu papel na transmissão da raiva ainda não são conhecidos. O objetivo da presente tese foi estudar os abrigos diurnos, os agrupamentos e o comportamento agonístico do morcego hematófago comum, Desmodus rotundus, e sua relação com a raiva dos herbívoros no Vale do Paraíba. Foi possível também obter informações sobre as duas outras espécies de morcegos hematófagos, especialmente de Diphylla ecaudata. Entre 2011 e 2014, dados sobre abrigos diurnos, composição dos agrupamentos, lesões corporais, diagnóstico de raiva e sorologia antirrábica de D. rotundus foram obtidos nos municípios de Jacareí, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca e São Luiz do Paraitinga no Vale do Paraíba, Sudeste do estado de São Paulo, Sudeste do Brasil. Foram estudados 14 abrigos diurnos de D. rotundus, dos quais 12 eram construções abandonadas na área rural. Desmodus rotundus partilhou abrigos diurnos com apenas cinco espécies de filostomídeos: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina e Anoura caudifer. O tempo de recolonização desses abrigos diurnos por D. rotundus foi em média 12,5 meses, com uma variação entre três e 25 meses. O tamanho dos agrupamentos variou de dois a 79 indivíduos, com uma média de 15,6 morcegos/grupo. Fêmeas foram encontradas em 15 agrupamentos, com uma média de 13 fêmeas e uma variação entre uma e 55 fêmeas/grupo. Por outro lado, machos estiveram mais presentes nos agrupamentos, ocorrendo em quase todos (N=21), com uma média de 7,1 machos/grupo e uma variação de um a 24 machos. Sete agrupamentos foram considerados de machos solteiros. Onze dos 22 agrupamentos eram constituídos de colônia e grupo de machos solteiros. O dimorfismo sexual no comprimento do antebraço de D. rotundus do Vale do Paraíba foi estatisticamente significativo e sugere que as fêmeas são maiores 13 do que os machos. Lesões corporais, atribuídas às mordeduras provocadas por outros morcegos, foram encontradas em 76,7 por cento dos indivíduos de D. rotundus, tanto em machos como em fêmeas. A região mais atingida foram as membranas alares, com 68 por cento , porém lesões nas orelhas, face e membros foram menos frequentes (23,1 por cento nas fêmeas e 26,9 por cento nos machos). Acredita-se que as lesões nessas regiões sejam mais importantes nos mecanismos de transmissão de raiva. Apesar de ter analisado 310 amostras de encéfalos de D. rotundus do Vale do Paraíba, o resultado foi negativo em todas as amostras. A sorologia mostrou que todos os morcegos apresentaram positividade em diferentes graus. Contudo, se considerarmos o ponto de corte 0,5 UI/ml, o número de indivíduos positivos caiu para 30,1 por cento (N=90), sendo 30,9 por cento nas fêmeas e 28,8 por cento em machos. Apesar de nenhum indivíduo de D. rotundus positivo para a raiva ter sido encontrado no Vale do Paraíba durante a presente tese, a sorologia positiva de, pelo menos, 30 por cento mostra que há vírus da raiva circulando em sua população. Essa alta circulação viral pode ter sido favorecida pelas interações agonísticas, que causam lesões em mais de 75 por cento dos morcegos, a formação compacta (em penca) dos agrupamentos, o grooming social, a reciprocidade e partilha alimentar / Despite the hematophagous bats are very studied, many aspects of their biology and their role in the transmission of rabies are not yet known. The aim of this thesis was to study the diurnal shelters, groups and the agonistic behavior of the common hematophagous, Desmodus rotundus, and its relation to the cattle rabies in the Paraíba Valley. It was also possible to obtain information about the two other species of vampire bats, especially Diphylla ecaudata. Between 2011 and 2014, data on diurnal shelters, composition of groups, body injuries, diagnosis of rabies and rabies serology D. rotundus were gathered from the cities of Jacarei, Paraibuna, Pindamonhangaba, Salesópolis, Santa Branca and São Luiz do Paraitinga in the Valley Paraíba, Southeastern of São Paulo State, Southeastern Brazil. Fourteen diurnal shelters of D. rotundus were studied here and 12 were abandoned buildings in rural areas. Desmodus rotundus shared daytime shelters with only five species of phyllostomid bats: Diphylla ecaudata, Chrotopterus auritus, Carollia perspicillata, Glossophaga soricina and Anoura caudifer. The time of recolonization of these roosts by D. rotundus was on average 12.5 months, ranging from three to 25 months. The size of the groups ranged from two to 79 individuals, with a mean of 15.6 bats/group. Females were found in 15 groups with an average of 13 females/group and ranging between one and 55 females. Moreover, males were present in most groups from Paraíba Valley, occurring in almost all (N = 21), with an average of 7.1 males/group, and a variation of 24 males. Seven groups were considered to be single males groups. Eleven of the 22 groups were made up of colony and single male groups. Sexual dimorphism in the forearm length of D. rotundus from the Paraíba Valley was statistically significant and suggests that females are larger than males. Body Injuries, attributed to bites caused by other bats were found in 76.7 per cent of individuals of D. rotundus, in both males and females. The most affected region was the wing membranes, with 68 per cent , but lesions on the ears, face and limbs were less frequent (23.1 per cent in females and 26.9 per cent in males). It is believed that injuries in these regions are more important in the rabies transmission mechanism. Despite having analyzed 310 samples of brains of D. rotundus from the Paraíba Valley, the result was negative in all samples. Serology showed that all bats were positive in varying degrees. However, if we consider the cut off 0.5 IU/ml, the number of positive samples dropped to 30.1 per cent (N = 90) and 30.9 per cent in females and 28.8 per cent males. Although no individual of D. rotundus positive for rabies was found in the Paraíba Valley during this thesis, the positive serology at least 30 per cent shows that there is rabies virus circulating in this bat population. This high viral circulation may have been favored by agonistic interactions, that cause lesions in more than 75 per cent of the bats, the compact formation (in clusters) of groups, social grooming, reciprocity and food sharing.
234

Dimorfismo sexual no modelo de infarto do mioc?rdio em ratos: aspectos neuroend?crinos e auton?micos cardiovasculares / Sexual dimorphism in the myocardial infarction model in rats: neuroendocrine and autonomic cardiovascular aspects

Souza, Natalia Soares Carvalho de 26 August 2014 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-03T14:02:59Z No. of bitstreams: 1 2014 - Natalia Soares Carvalho de Souza.pdf: 1833535 bytes, checksum: 4574c94ab4a477d9f8d0ddf31d6b4069 (MD5) / Made available in DSpace on 2017-05-03T14:03:00Z (GMT). No. of bitstreams: 1 2014 - Natalia Soares Carvalho de Souza.pdf: 1833535 bytes, checksum: 4574c94ab4a477d9f8d0ddf31d6b4069 (MD5) Previous issue date: 2014-08-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Premenopausal women are less prone to develop cardiovascular diseases than men and this advantage do not persist in postmenopausal women. Thus herein we aimed to investigate the gender difference and the estrogen influence in cardiac function, fluid balance and thyroid status, in Wistar rats subjected to experimental model of myocardial infarction (MI). In the first step, adult male (n = 18) and female (n = 21) rats underwent experimental MI (MIm and MIf,) or sham-operation (ShamM and ShamF) respectively. One and four weeks post-MI rats were placed in metabolic cages, subjected to echocardiography (ECHO), electrocardiography and then euthanized for blood sample collection and tissue collection (heart, lung and liver). In the second step female rats were ovariectomized (n = 24) or continued intact (n = 21), two weeks later they were subjected to MI (MIOVX and MIINT, respectively) or sham operation (ShamOVX and ShamINT). Four weeks post-MI, they were subjected to the same evaluations of the first step, not only the electrocardiography. In the third step, female rats were subjected to ovariectomy and treated with estrogen (E2) (n = 13) or vehicle (n = 22). Two weeks later they underwent experimental MI (MIOVX+E2 and MIOVX+Veh). Four weeks post-MI they were subjected to the same evaluations of the second step. Male infarcted rats developed cardiac dysfunction (shortening fraction, SF, reduction, ~ 70%) and fluid homeostasis changes (sodium intake increasing, ~ 146% and urinary volume reduction, ~55%) earlier than female, in the first week post-MI while female presented these changes (SF reduction, ~28% and sodium intake increasing, ~143%) only in the fourth week and attenuated compared to male. MIM showed reduction in LF/HF ratio (~70%), one week post-MI. And only male rats presented hypothyroidism after MI (T4 ~52% and T3 ~38%, reduction). We also verified reduction in SF (~55%), increasing in LA/Ao ratio (~75%) and changes in fluid balance (sodium intake reduction, ~67% and urinary volume reduction, ~40%) more pronounced in MIOVX than in MIINT. MIOVX group reduced thyroid hormone levels after MI (T3 ~35%). MIOVX+Veh showed more pronounced reduction in SF (~55%) and increasing in LA/Ao ratio (~75%) than the MIOVX+E2 group. The sodium intake reduced in MIOVX+Veh (~67%) and in the urinary volume we verified significant reduction in ShamOVX+Veh and MIOVX+Veh groups compared to ShamOVX+E2 and MIOVX+E2 groups (P < 0.05). Serum T3 reduced significantly (~35%) only in MIOVX+Veh group. The pathophysiological development of heart failure post-MI was attenuated in female compared to male. And female rats subjected to MI presented fluid balance more favorable and related to the less pronounced development of heart failure. Estrogen seems to influence positively the cardiac function and attenuate the dysfunction that occur post-MI. The euthyroid status in female intact do not seems to be determinant to the less pronounced development of heart failure / Sabe-se que mulheres na pr?-menopausa apresentam menor preval?ncia de doen?as cardiovasculares do que homens e, esta diferen?a desaparece ap?s a menopausa. Sendo assim, o presente estudo buscou avaliar o dimorfismo sexual e a influ?ncia do estr?geno nas altera??es da fun??o card?aca, do equil?brio hidroeletrol?tico e do status tireoidiano de ratos Wistar submetidos ao infarto do mioc?rdio (IM) experimental. Na primeira etapa ratos wistar machos (n = 18) e f?meas (n = 21) foram submetidos ao infarto experimental (INF.M e INF.F) ou ? falsa cirurgia (Sham.M e Sham.F). Na primeira e quarta semana p?s-IM foram colocados em gaiolas metab?licas e submetidos ? ecodopplercardiografia (ECO) e eletrocardiografia (an?lise espectral), seguido de eutan?sia para coleta de sangue (dosagem s?rica de horm?nios tireoidianos) e de tecidos (cora??o, pulm?o e f?gado, para biometria). Na segunda etapa, f?meas foram ovariectomizadas (n = 24) ou mantidas intactas (n = 21) e ap?s duas semanas submetidas ao infarto do mioc?rdio (INFOVX e INFINT) ou ? falsa cirurgia (ShamOVX e ShamINT). Quatro semanas ap?s p?s-IM, as mesmas avalia??es da etapa anterior foram realizadas exceto a eletrocardiogr?fica. Na terceira etapa, foi realizada ovariectomia e reposi??o com estr?geno (E2) ( n = 13) ou ve?culo (n = 22). Ap?s duas semanas foi realizada a cirurgia de indu??o ao infarto (INFOVX+E2 e INFOVX+Veic) e a falsa cirurgia (ShamOVX+E2 e ShamOVX+Veic). Decorridas quatro semanas foram feitas as mesmas avalia??es da segunda etapa. O grupo INFM desenvolveu disfun??o card?aca (fra??o de encurtamento, FEnc%, ~70% de redu??o) e altera??es na regula??o hidroeletrol?tica (aumento do apetite por s?dio, ~146% e redu??o do volume urin?rio, ~55%), uma semana p?s-IM e, portanto, mais cedo que as f?meas, que apresentaram altera??es na fun??o card?aca (FEnc%, ~28% de redu??o) e regula??o hidroeletrol?tica (aumento do apetite por s?dio, ~143%) na quarta semana p?s-IM. O grupo INFM apresentou redu??o na rela??o LF/HF (~70%), uma semana p?s-IM. E, apenas os ratos machos desenvolveram hipotireoidismo ap?s o infarto. Tamb?m foi observada redu??o da FEnc% (~55%), aumento da rela??o ?trio esquerdo/ aorta (AE/Ao, ~75%) e altera??es na regula??o hidroeletrol?tica (redu??o do apetite por s?dio, ~67% e do volume urin?rio, ~40%) mais pronunciadas em INFOVX do que em INFINT. O grupo INFOVX tamb?m apresentou redu??o dos n?veis s?ricos de T3 (~35%) p?s-IM. O grupo INFOVX+Vei mostrou redu??o da FEnc% (~55%) e aumento na rela??o AE/Ao (~75%) mais pronunciadas que o grupo INFOVX+E2. INFOVX+Vei reduziu o apetite por s?dio (~67%) e, no volume urin?rio, foi observada redu??o significativa nos grupos ShamOVX+Vei e INFOVX+Vei em rela??o aos grupos ShamOVX+E2 e INFOVX+E2 (P<0,05). O T3 s?rico reduziu significativamente (~35%) apenas no grupo INFOVX+Vei. Houve diferen?a no desenvolvimento fisiopatol?gico da insufici?ncia card?aca (IC) p?s- IM entre machos e f?meas, sendo mais brando nas f?meas. E f?meas infartadas apresentaram uma regula??o hidroeletrol?tica mais favor?vel e compat?vel com o desenvolvimento menos acentuado da IC. O estr?geno influenciou positivamente a regula??o hidroeletrolitica de f?meas infartadas, o que favoreceu a fun??o card?aca e atenuou desta forma, a disfun??o que ocorre ap?s o infarto. A manuten??o do status eutire?ideo n?o pareceu ser determinante para o desenvolvimento menos pronunciado da IC
235

Etude de la variabilité génétique et de la phylogéographie de Santiria trimera (Burseraceae) - implications pour une conservation durable des forêts humides d’Afrique / Study of the genetic variability and the phylogeography of Santiria trimera (Burseraceae) – implications for a sustainable conservation of African rainforests.

Koffi, Kouamé Guillaume K. G. 22 November 2010 (has links)
La phylogéographie intègre l’information géographique et génétique pour inférer l’histoire démographique et les processus évolutifs des espèces. La présente étude recherche à travers les patrons de différenciation de l’ADN chloroplastique (ADNcp) au sein de Santiria trimera (Oliv.) H.J.LAM ex AUBR. [Emend. ONANA] la reconstitution d’une histoire des végétations des écosystèmes de forêts tropicales humides d’Afrique. Le modèle S. trimera est un arbre dioïque endémique des forêts humides d’Afrique dont les drupes sont dispersées par les primates et les oiseaux. Les formes morphologiques de ce modèle sont très variables et suscitent la délicate question de délimitation des espèces. Trois régions de l’ADNcp (l’intergène trnL-F, une portion du gène rbcL et l’intron rpl36-infA-rps8) ont été séquencées chez 377 individus issus de 42 populations de l’île de São Tomé, du Haut- et Bas-Guinéen pour étudier la phylogéographie. Des arbres phylogénétiques ont été réalisés sur des séquences d’un intron nucléaire du gène Phosphoenolpyruvate Carboxylase (72 individus) et sur les trois régions chloroplastiques. Une analyse morphométrique a été réalisée sur des données collectées sur des arbres en fruits. A l’aide de 10 locus microsatellites nucléaires, nous avons déterminé la structure génétique entre trois morphotypes sympatriques et analysé la structure génétique spatiale au sein de chaque groupe génétique. Le séquençage de l’ADNcp a mis en évidence des doubles pics sur les chromatogrammes de séquences. L’analyse des séquences clonées de produits PCR, la distribution des sites à doubles pics dans les séquences et dans les populations et les états ancestraux des positions à doubles pics nous ont permis d’interpréter les doubles pics comme résultant d’une co-amplification d’une copie chloroplastique et de copies nucléaires des régions séquencées. Les pics majeurs ont été considérés comme les nucléotides d’ADNcp d’origine maternelle et les pics mineurs ont été exclus de notre jeu de données. Les domaines phytogéographiques de São Tomé, du Haut- et Bas-Guinéen ne partagent aucun haplotype chloroplastique. Le Bas-Guinéen montre une plus grande diversité génétique. Les zones de distribution des haplotypes rares coïncident avec les refuges forestiers hypothétiques. L’analyse morphométrique et la phylogénie des séquences d’ADNcp suggèrent conjointement la reconnaissance de deux espèces bien différenciées. La structure génétique au sein d’une même population présumée suggère que les trois morphotypes en sympatrie dans les populations du Gabon constituent deux réservoirs génétiques différenciés sans individus hybrides. Selon le Concept Biologique de l’Espèce, S. trimera est probablement un mélange de deux espèces. On peut définir une espèce constituée d’individus avec des racines échasses et petites folioles coriaces (SRsl) et une seconde espèce constituée à la fois d’individus avec des racines échasses et de grandes folioles papyracées (SRll) et d’individus sans racine échasse avec de grandes folioles coriaces (NSR). Au vu de ces résultats, la classification taxonomique de S. trimera nécessite une révision. La confusion de ces deux espèces dans les forêts du Gabon explique une plus forte divergence de lignées chloroplastiques sympatriques par rapport aux lignées issues des régions biogéographiques isolées. L’un des deux haplotypes principaux de l’espèce à grandes folioles (SRll + NSR) est distribué dans le nord du Gabon et l’autre est distribué dans le sud. Au sein de l’espèce à petites folioles (SRsl), les zones d’endémisme de lignées chloroplastiques se situent dans l’Ouest du Cameroun qui est considéré comme une zone de fort endémisme et de forte diversité en espèces. Globalement, les patrons phylogéographiques mis en évidence entre lignées chloroplastiques de S. trimera sont compatibles avec les hypothèses biogéographiques basées sur les patrons de diversité et d’endémisme des espèces. / Phylogeography combines geographic and genetic information to infer demographic history and evolutionary processes. The present study of the spatial structure of chloroplast DNA (cpDNA) within Santiria trimera H.J.LAM ex AUBR. [Emend. ONANA], a primate- and bird-dispersed dioecious tree typical of African rainforests, provides insights into African vegetation history. This tree displays striking morphological variation which poses the problem of species delineation. Three regions of cpDNA (intergene trnL-F, a portion of rbcL gene and intron rpl36-infA-rps8) were sequenced in 377 individuals from 42 populations from São Tomé island and from Upper- and Lower-Guinean forests to study phylogeography. To study genetic divergence among morphotypes of S. trimera, phylogenies of a nuclear intron of Phosphoenolpyruvate Carboxylase from 72 individuals and concatenated sequences of the three cpDNA sequences were compared to morphological data from fruit-bearing trees. Using ten nuclear microsatellite markers, we defined the genetic structure among three sympatric morphotypes and analysed the spatial genetic structure within each genetic group. CpDNA sequences revealed double-peaks on sequence chromatograms. Sequences of cloned PCR products, the distribution of double peaks on sequences and in populations and ancestral nucleotides inferred from different taxa of the Burseraceae family enabled us to deduce that double peaks were due to the co-amplification of chloroplast and nuclear copies of the cpDNA region. Major peaks were considered as originating from maternal cpDNA. Subordinated peaks corresponding to the nuclear copies were excluded from our data set. The phytogeographic domains of São Tomé, Upper and Lower Guinea did not share any haplotype. Lower Guinea was the most diversified and the most divergent haplotypes were found in Gabonese forests. Endemism areas of haplotypes coincide with hypothetic forests refuges. Morphometric analyses and phylogenies cpDNA converge to delineating two well-differentiated species within S. trimera. Likewise, the genetic structure within one assumed population suggests that the three sympatric morphotypes constitute two genetically isolated populations without any hybrid. Following the Biological Species Concept, S. trimera is probably a mixture of two species in Lower Guinean forests. The first species is composed of all individuals with stilt roots and small leaflets (SRsl) and the second one is composed of both the morphotype with stilt roots, large and thin leaflets (SRll) and the morphotype without stilt roots with large and tough leaflets (NSR). In the view of our results, the taxonomical classification of S. trimera requires a revision. The confusion of both species in Gabonese forests explains that the highest divergence among chloroplast lineages was found in sympatric populations instead of among isolated biogeographic regions. One of the two major haplotypes of the second species (NSR + SRll) was distributed in the north of Gabon while the other haplotype was distributed in the south. Within the species with small leaflets (SRsl), areas of elevated haplotype endemism in West Cameroon coincided with hypothetic forest refuges. Overall, phylogeographic patterns within our model were in accordance with biogeographic hypotheses based on species endemism and diversity patterns.
236

Συστηματική και βιολογία των κεφαλοπόδων στο Βόρειο Αιγαίο

Λευκαδίτου, Ευγενία 02 December 2008 (has links)
Σκοπός της παρούσας διατριβής, ήταν α) η μελέτη της συστηματικής των Κεφαλοπόδων και ειδικώτερα της κατανομής και των συναθροίσεών τους στο Θρακικό πέλαγος και τους κόλπους Στρυμωνικό, Συγγιτικό, Τορωναίο, Θερμαϊκό και β) η μελέτη του βιολογικού κύκλου των ειδών Loligo vulgaris (καλαμάρι), Illex coindetii (θράψαλο) και Sepietta oweniana. Το υλικό που χρησιμοποιήθηκε προήλθε κυρίως από 8 δειγματοληψίες (9/91 – 12/93) που πραγματοποιήθηκαν από το EΛ.ΚΕ.Θ.Ε., με τράτα βυθού, σε βάθη 17- 400 m. Για τη μελέτη της βιολογίας των 2 Τευθοειδών το υλικό συμπληρώθηκε με μηνιαία λήψη δειγμάτων (2/92 – 6/93) από την επαγγελματική αλιεία στο ΒΑ Αιγαίο. Συνολικά προσδιορίστηκαν 28 είδη Κεφαλοπόδων, από 8 διαφορετικές οικογένειες: Enoploteuthidae (1 είδος), Histioteuthidae (1 είδος), Loliginidae (3 είδη), Ommastrephidae (3 είδη), Sepiidae (3 είδη), Sepiolidae (9 είδη), Argonautidae (1 είδος) και Octopodidae (7 είδη). Πολυπαραγοντικές αναλύσεις των λογαριθμικά τροποποιημένων δεδομένων αφθονίας των ειδών ανά δειγματοληπτική σύρση, έδειξαν διαφοροποιήσεις στη δομή των συναθροίσεων των Κεφαλοπόδων κατά κύριο λόγο με το βάθος και σε μικρότερο βαθμό με την εποχή και τη γεωγραφική περιοχή δειγματοληψίας. Στα είδη I. coindetii και S. oweniana διαπιστώθηκε αναπαραγωγική δραστηριότητα καθόλη τη διάρκεια του χρόνου, με μέγιστη ένταση αντίστοιχα το φθινόπωρο και χειμώνα – άνοιξη. Η αναπαραγωγική περίοδος για το νηριτικό L. vulgaris ήταν σχετικά πιό περιορισμένη (μέσα χειμώνα - αρχές φθινοπώρου) με μέγιστη ένταση την άνοιξη. Η ηλικία των 2 τευθοειδών, που εκτιμήθηκε απο την ανάγνωση των αυξητικών δακτυλίων σε στατολίθους, δεν ξεπερνά τους 14 μήνες ενώ ο ημερήσιος ρυθμός αύξησης του μανδύα φτάνει για το καλαμάρι τα 2-2,5 mm και για το θράψαλο τα 0,5-0,6 mm. Οι Οστειχθείς και τα Κεφαλόποδα αποτελούσαν τις πιο συχνά εμφανιζόμενες λείες στο στομαχικό περιεχόμενο των δύο Τευθοειδών, ενώ τα Καρκινοειδή την προτιμώμενη λεία για το είδος S. oweniana. / The twofold aim of this study was: firstly to contribute to the knowledge of the cephalopod species taxonomy in the Greek Seas, focusing particularly on faunistic composition at the N. Aegean (ΝΕ Mediterranean), and secondly to investigate the life history patterns of the species Loligo vulgaris, Illex coindetii and Sepietta oweniana. Faunistic study was based on samples collected from the N. Aegean Sea (N>39ο 50΄) during eight trawl surveys (9/91 – 12/93), carried out at depths 17 - 400 m. For the study of the two squid species biology, additional monthly samples were collected from commercial fishery in NE Aegean Sea during the period February 1992 - June 1993. In all, 28 species of cephalopods belonging to 8 families were identified including Enoploteuthidae (1 species), Histioteuthidae (1 species), Loliginidae (3 species), Ommastrephidae (3 species), Sepiidae (3 species), Sepiolidae (9 species), Argonautidae (1 species) and Octopodidae (7 species). To detect zonation patterns in cephalopod community structure, multivariate analyses of species abundance data per haul were performed. Considerable variability was shown in assemblage structure, determined primarily by depth, and to a lesser extent, by geographical location and season. Intermittent terminal spawning pattern has been shown for all 3 examined species. Spawning occurs throughout the year for I. coindetii and S. oweniana in the N. Aegean Sea, peaking respectively in autumn and winter-spring, as indicated by minimum ML50 values. The breeding season of neritic L. vulgaris extends from late winter to early autumn, with spawning intensity varying among years, due to variation in temperature and population age structure. Age of both teuthoid species, estimated by growth increment counts on statoliths, did not exceed 14 months. Daily growth rate (DGR) reached 2-2,5 mm in L. vulgaris and 0,5-0,6 mm in I. coindetii. L. vulgaris and I. coindetii feed primarily on fishes and cephalopods in the N. Aegean Sea, whereas S. oweniana on crustacean and fishes.
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Lietuvos kiaunių populiacijų kokybė / Quality of Lithuanian Martens populations

Šidlauskas, Giedrius 21 June 2013 (has links)
Atlikus Lietuvoje gyvenančių kiaunių gausos ir sumedžiojimo analizę nustatyta, kad pastarąjį dešimtmetį Lietuvoje kasmet vidutiniškai sumedžiojama apie 500 kiaunių. Tendencija didėjanti. Iki šiol nežinoma kiek kiaunių sumedžiojama pagal atskiras jų rūšis. Naudojant du skirtingus amžiaus nustatymo metodus, abiejų kiaunių rūšių (M. martes ir M. foina) pirmamečių individų nustatyta daugiau nei suaugusių. Pirmamečių miškinės kiaunės patelių buvo nustatyta 12,5 % daugiau nei pirmamečių patinų. Nustatyta, kad abiejų kiaunių rūšių patinai buvo stambesni už pateles, tačiau jų lytinis dimorfizmas nėra stipriai išreikštas. Abiejų kiaunių rūšių patinai statistiškai patikimai skyrėsi tik pagal kūno masės ir krūtinės apimties duomenis (p< 0,1). Ištyrus Lietuvos kiaunių užsikrėtimą trichinelioze, konstatuota, kad 8,3 proc. kiaunių nustatyta Trichinella sp., o 1 g raumenų vidutiniškai rasta 1 šio parazito lerva. / After the assessment of martens abundance and hunting analysis stated that in past ten years in Lithuania the hunted martens are 500. The hunting tendency and numbers are growing. At this moment is unknown number about hunting different species individually (M. martes & M. foina). In this population first year specimens was dominating against adults. First year Pine marten female in population was 12,5 % more than first year males. Both species martens males were larger than females, but the sexual dimorphism wasn’t strong . Both species males had two different statistically positive features – body weight and chest size (p< 0,1). Investigated Lithuanian martens from trichinelosis was determined that 8,3 % martens has Trichinella spp. and in 1g. Muscle in average was found 1 this parasite larvae.
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Altitudinal Effects on The Behavior and Morphology of Pygmy Tarsiers (Tarsius pumilus) in Central Sulawesi, Indonesia

Grow, Nanda Bess 16 December 2013 (has links)
Pygmy tarsiers (Tarsius pumilus) of Central Sulawesi, Indonesia are the only species of tarsier known to live exclusively at high altitudes. This study was the first to locate and observe multiple groups of this elusive primate. This research tested the hypothesis that variation in pygmy tarsier behavior and morphology correlates with measurable ecological differences that occur along an altitudinal gradient. As a response to decreased resources at higher altitudes and the associated effects on foraging competition and energy intake, pygmy tarsiers were predicted to exhibit lower population density, smaller group sizes, larger home ranges, and reduced sexually selected traits compared to lowland tarsiers. Six groups containing a total of 22 individuals were observed. Pygmy tarsiers were only found between 2000 and 2300 m, indicating allopatric separation from lowland tarsiers. As expected, the observed pygmy tarsiers lived at a lower density than lowland tarsier species, in association with decreased resources at higher altitudes. The estimated population density of pygmy tarsiers was 92 individuals per 100 ha, with 25 groups per 100 ha. However, contrary to expectation, home range sizes were not significantly larger than lowland tarsier home ranges, and average NPL was smaller than those of lowland tarsiers. The average home range size for the observed pygmy tarsiers was 2.0 ha, and the average nightly path length (NPL) was 365.36 m. Pygmy tarsiers exhibited a nonrandom, clumped distribution near forest edges. While insect abundance and biomass were found to decrease as altitude increased, insect abundance and biomass was higher along anthropogenic edges. Thus, tarsiers within the study area may mitigate the decreased availability of insects at high altitudes by remaining close to forest edges, which in turn may be related to smaller than expected home range sizes. Further, estimates of pygmy tarsier abundance may be inflated because of increased insect abundance along anthropogenic edges. Contrary to the prediction for smaller group sizes as a response to feeding competition, the observed pygmy tarsiers lived in relatively large groups with multiple adult males. However, in support of the prediction for energetic constraints on body proportions, the observed pygmy tarsiers did not exhibit sexually selected traits. The pygmy tarsiers exhibited low sexual dimorphism and small relative testes mass, a trend opposite from lowland tarsier species, which may indicate a constraint on the development of those traits. Considered together, these results suggest that the observed pygmy tarsiers have adapted to life in an environment with limited resources. Future studies should explore the possible contributing effects of seasonality and topography.
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Getting to the root of the matter: grizzly bears and alpine sweetvetch in west-central Alberta, Canada

Coogan, Sean C P Unknown Date
No description available.
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Metapopulations dynamics and sex-specific resource allocation in Silene dioica

Peedu, Elisabet January 2018 (has links)
Rising archipelagos provide unique settings for the study of the temporal and spatial dynamics of their biota. This offers the possibility to study the ecology and genetics of early successional processes; both between islands that differ in age and within islands when already established organisms have to keep pace with the changing environment. I have worked in the Skeppsvik Archipelago housing about 100 islands that due to land uplift vary in age, thus representing various stages of primary succession. I have utilized a naturally created metapopulation of Silene dioica, which in this archipelago is a dominant plant of the deciduous border, offering the possibility to study subpopulations on islands of different ages and in different phases of primary succession. Many plant species exist as metapopulations, which consists of many local populations which may differ in size and degree of connectivity. Metapopulations are further characterized by recurrent colorizations and extinctions of local populations, meaning that a species continually must disperse and relocate to allow for persistence in this system. For a dioecious plant species, gene flow is in the shape of seeds and pollen and to allow for the persistence of populations, it is necessary that levels of seed dispersal and pollen gene flow are enough to ensure both colonisation, establishment and subsequent population growth. Levels of seed dispersal and pollen gene flow is in turn influenced by how the two sexes partition resources between reproduction, growth and survival. In paper I, I combined a field survey, a common garden experiment and a nine-year demographic study to assess the demographic consequences of sex-specific resource allocation and to investigate if differential costs of reproduction may be a driver in the evolution of sexual dimorphism in dioecious Silene dioica. Significant somatic intersexual dimorphism was found with females being the larger sex, both in terms of above – and belowground biomass. Furthermore, the reproductive effort of females exceeds that of males across a growing season which largely confirms what has been observed earlier in dioecious, herbaceous plant species. According to the cost of reproduction hypothesis, high reproductive investment should result in trade-offs with somatic and/or life-history traits. Somatic trade-offs were not observed, and instead I found strong, positive associations between reproductive investment and vegetative growth in both males and females. Compensation mechanisms were found in both sexes although females are generally more efficient at compensating their reproductive costs. At the end of a flowering season, after having paid the current costs of reproduction, females are better than males at provisioning perennial roots and rosettes potentially influencing the ability to set future flower buds and winter survival. Trade-offs were found between current and future reproduction and survival, but this is condition dependent and compensation through frequency of flowering plays an important role. The cost of reproduction hypothesis appears to play some role in driving the somatic and demographic sexual dimorphisms observed in this system but sexual selection acting on males will be a fruitful avenue for future research. In paper II, I investigated the population genetic consequences of metapopulation dynamics in Silene dioica. The occurrence of islands in different phases of primary succession together with successional gradients across islands, makes it possible to investigate the genetic dynamics occurring in an age-structured metapopulation across several hierarchical levels. Genetic diversity and differentiation were estimated in eight young, recently colonised populations and in ten populations of an intermediate successional stage. Young populations were less genetically diverse compared to older populations, indicating that bottlenecks, created by small founding groups derived from a limited number of source populations, reduce the genetic diversity within newly founded populations. The observation of strong genetic structure both between islands and between patches with islands, indicates that gene flow is restricted across several spatial levels in this system. However, the lack of statistically significant differences in genetic differentiation between young and intermediate populations, indicates that levels of gene flow may not be high enough to reduce the genetic differentiation that arise from the initial founder event. The patterns of sexual dimorphism and the roles of males and females in Silene dioica have evolved to allow persistence in an ecological and population context of this species. The nature of this habitat, where islands rise up from the sea creating new environments for colonisation while at the same time, autogenic primary succession processes eventually leads to extinction, means that S. dioica continuously must relocate within successional phases for its persistence. The obvious success of this dioecious plant is apparent as it is one of the few dominant species in the deciduous border. This suggests that levels of seed dispersal and gene flow are sufficient enough to allow for establishment and persistence of island populations and that the sexual dimorphisms that have evolved in this metapopulation system act to increase levels of gene flow. The "live hard – die young" strategy, with extensive flowering bouts, which we find in the males may have evolved as a way of maintaining sufficient levels of genetic diversity in the metapopulation but will only be a possible strategy if there are continuous opportunities for re-establishments. Thus, the continuous land uplift that is occurring in the northern part of the Gulf of Bothnia may very well be a prerequisite for the long-term persistence of this dioecious, perennial plant species. / Landhöjningsprocesser i skärgårdsmiljöer skapar nya habitat som gör det möjligt att studera naturliga populationer i ett rumsligt och tidsmässigt sammanhang. Detta möjliggör studier av ekologi och genetik i tidiga successionsprocesser, både mellan öar som skiljer sig åt åldersmässigt och inom öar, där redan etablerade organismer måste anpassa sig till en föränderlig miljö. Jag har utfört studier i Skeppsviks skärgård som rymmer cirka 100 öar. På grund av landhöjningen så varierar dessa öar i ålder och de representerar således olika stadier i primärsuccession. Jag har använt mig av en naturlig Silene dioica metapopulation lokaliserad i Skeppsviks skärgård. Många växtarter existerar i metapopulationer, vilket består av ett antal lokala populationer som kan skilja sig åt i storlek och grad av anknytning. Metapopulationer kännetecknas även av återkommande koloniseringar och utrotningar av lokala populationer, vilket innebär att en art kontinuerligt måste sprida sig för att garantera sin fortlevnad i detta system. Genflöde inom dioika växtarter är i form av pollen och frön, och för att populationer skall kunna överleva så är det nödvändigt att nivåerna av fröspridning och pollen-genflöde är tillräckliga för att säkerhetsställa både kolonisering, etablering och efterföljande populationstillväxt. Nivåer av fröspridning och pollen-genflöde påverkas i sin tur av hur de två könen partitionerar resurser mellan reproduktion, tillväxt och överlevnad. I den första studien har jag kombinerat en fältundersökning, ett frilandsexperiment och en nioårig demografisk studie för att undersöka de demografiska konsekvenserna av könsspecifik resursallokering och för att utreda om könsspecifika skillnader i reproduktiv kostnad kan vara en drivkraft för evolutionen av sexuell dimorfism hos den dioika växten Silene dioica. Jag upptäckte signifikant somatisk intersexuell dimorfism där honor hade betydligt mer ovanjordisk och underjordisk biomassa jämfört med hanar. Över en växtsäsong så investerar honorna mer resurser i reproduktion, vilket i stor utsträckning bekräftar vad som tidigare har observerats i örtartade, dioika växter. Enligt hypotesen för reproduktiv kostnad så bör en hög investering i reproduktion leda till trade-offs med somatiska egenskaper, t.ex. tillväxt. Jag observerade inga somatiska trade-offs och istället fann jag positiva associationer mellan reproduktion och tillväxt hos både honor och hanar. Båda könen verkar ha utvecklat kompensationsmekanismer, även om honorna generellt är mer effektiva i hur de kompenserar för sina reproduktiva kostnader. Vid slutet av en växtsäsong, efter att ha betalat för de nuvarande reproduktiva investeringarna, så är honor bättre än hanar på att allokera resurser till fleråriga strukturer, såsom bladrosetter och rötter. Detta kan potentiellt påverka hur de anlägger sina knoppanlag för nästkommande år och hur väl de överlever vintern. Trade-offs hittades mellan nuvarande reproduktion och framtida reproduktionsmöjligheter och överlevnad men detta var habitat-specifikt och kompensation med hjälp av hur ofta en växt blommar under sin livstid spelar en viktig roll. Hypotesen för reproduktiv kostnad verkar vara en del av förklaringen till den somatiska och demografiska könsdimorfism som observerats i detta system men sexuell selektion, som verkar på hanar, kan vara ett möjligt område för framtida studier. I den andra studien undersökte jag populationsgenetiska konsekvenser av metapopulationsdynamik i Silene dioica. Förekomsten av öar i olika faser av primär succession tillsammans med olika grader av succession inom öar gör det möjligt att undersöka den genetiska dynamiken som uppträder i en åldersstrukturerad metapopulation över flera hierarkiska nivåer. Genetisk mångfald och differentiering uppskattades i åtta unga, nyligen koloniserade populationer och i tio populationer av ett intermediärt successionsstadium. Unga populationer hade lägre genetisk diversitet jämfört med äldre populationer, vilket indikerar att genetiska flaskhalsar, skapade av fåtal antal koloniserande individer, s.k. founders, som härrör från ett begränsat antal källpopulationer, minskar den genetiska diversiteten inom nybildade populationer. Observationen av stark genetisk strukturering, mellan och inom öar, indikerar att genflödet är begränsat över flera rumsliga nivåer i detta system. Bristen på statistiskt signifikanta skillnader i genetisk differentiering mellan unga och intermediära populationer indikerar emellertid att nivåer av genflöde kanske inte är tillräckligt höga för att minska den genetiska differentieringen som uppstår från den ursprungliga founder-händelsen. Mönstren av sexuell dimorfism och hanarnas och honornas roll har utvecklats för att möjliggöra fortlevnad i ett ekologisk och populationsmässigt sammanhang hos Silene dioica. I denna livsmiljö, där öar stiger upp ur havet och skapar nya miljöer för kolonisering samtidigt som autogena primära successionsprocesser leder till utrotning, måste S. dioica kontinuerligt sprida sig mellan olika successionsfaser för att överleva. Den uppenbara framgången för den här dioika växten är uppenbar eftersom den är en av de få dominerande arterna i lövkanten. Detta tyder på att nivåer av fröspridning och genflöde är tillräckliga för att möjliggöra etablering och beständighet av ö-populationer och att de sexuella dimorfismer som har utvecklats i detta metapopulationssystem verkar för att öka nivåerna av genflöde. "Lev hårt – dö ung" -strategin med omfattande blomningar som vi finner hos hanarna kan ha utvecklats som ett sätt att upprätthålla tillräckliga nivåer av genetisk diversitet i metapopulationen men den kommer endast att vara en möjlig strategi om det finns kontinuerliga möjligheter för re-etableringar. Således kan den kontinuerliga landupphöjningen som förekommer i norra delen av Bottniska viken mycket väl vara en förutsättning för den långsiktiga beständigheten av denna dioika, fleråriga växtart. / <p>Felaktigt angivet "Dissertation for PhD" i kolofon.</p>

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