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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.
71

DNA barcoding of different earthworms' species and their response to ecotoxicological testing / Laetitia Voua Otomo

Voua Otomo, Laetitia January 2015 (has links)
The ecotoxicological literature reveals that countless researchers worldwide rely upon informally identified commercial earthworm stocks for laboratory bioassays. The primary aim of this study was to investigate laboratory and commercial stocks of Eisenia species used in South Africa in order to confirm their taxonomy, assess their levels of genetic richness and differentiation. To do so, populations of potential Eisenia andrei and Eisenia fetida were purchased/obtained from vermiculturists and laboratories from four provinces of South Africa. DNA barcoding was used to investigate these taxonomic uncertainties. The COI gene was partially amplified and sequenced in selected earthworms from eight local populations (focal groups) and two European laboratory stocks (non-focal groups). Only nine COI haplotypes were identified from the 224 sequences generated. One of these haplotypes was found to belong to the Megascolecidae Perionyx excavatus. The remaining eight haplotypes belonged to the genus Eisenia although only a single Eisenia fetida haplotype, represented by six specimens, was found in one of the European populations. The other seven haplotypes, all occurring in South Africa, were Eisenia andrei. No Eisenia fetida was found in the South African based populations. One of the commercial stocks from South Africa and a laboratory culture from Europe were mixes of E. andrei - P. excavatus and E. andrei – E. fetida respectively. COI haplotype numbers were limited to two to three distinct sequences within each of the local groups. This translated into a haplotype diversity (H) lower than 0.45 in all the populations, which is very low when compared to other such earthworm studies in which COI polymorphism has been investigated. Of all the local populations investigated, only the lone field population included was genetically divergent from the other populations. This was explained by the haplotype distribution across the populations which indicated that this population was the only one not harbouring the haplotype which represented 75% or more of the COI sequences within the local populations. Because research suggests that earthworm populations with limited genetic diversity may suffer inbreeding depression which could affect traits such as reproduction and survival, the secondary aim was to test whether metal-sensitive earthworms were overly present in the populations investigated. To do so, the three most common COI haplotypes identified between the 8 local populations of E. andrei (called Hap1, Hap2 and Hap3) were paired up and exposed to cadmium. A total of six couples were exposed to 0, 25, 50 and 100 mg Cd/kg for 4 weeks at 20ºC. The survival, biomass variation, cocoon production and cocoon hatching success were assessed for all the couples. The results indicated that couple 6 (Hap3xHap3) was the most sensitive for three of the endpoints assessed whereas couple 4 (Hap1 x Hap3) was the least sensitive. Cocoon hatching success could not help differentiate the couples. The analysis of Cd tissue contents revealed that with increasing Cd concentration, Cp6 (Hap3xHap3) could accumulate significantly more Cd than any other couple (p ≤ 0.01). These findings indicate that earthworm populations may carry intrinsically metal-tolerant and metal-sensitive genotypes. In the context of ecotoxicological testing, the present results underline the importance of using genetically diverse populations in laboratory testing as Cp6 (Hap3xHap3) could have suffered from the deleterious effect of inbreeding. Because E. fetida could not be found in the local populations assessed, it is recommended that further earthworm DNA barcoding studies, covering a more representative geographical area of South Africa and including more field populations of Eisenia spp. be conducted. Because of the occurrence of genetic homogeneity in the populations studied, it is suggested that captive breeding initiatives be established using specimens obtained from several geographically distant field and reared populations. Further research investigating patterns of Cd accumulation/excretion kinetics between the Cd-tolerant and Cd-sensitive individuals reported in the present study, should be conducted to help determine whether inbreeding is the sole factor explaining the observed genotypic responses to Cd. Finally, the necessity of a standardised earthworm barcoding protocol that could help both to properly identify laboratory earthworm stocks and to select genetically diverse stocks suitable for laboratory testing, is discussed together with the relevance of the present work to ecotoxicological testing in general. / MSc (Environmental Sciences), North-West University, Potchefstroom Campus, 2015
72

CHRONIC OPIOID USE IN FIBROMYALGIA SYNDROME: CHARACTERISTICS AND OUTCOMES

Painter, Jacob T. 01 January 2012 (has links)
Fibromyalgia syndrome (FMS) is a chronic pain condition with significant societal and personal burdens of illness. Chronic opioid therapy in the treatment of chronic nonmalignant pain has increased drastically over the past decade. This is a worrisome trend in general, but specifically, given the pathophysiologic characteristics seen in fibromyalgia syndrome patients, the use of this class of medication deserves special scrutiny. Although the theoretical case against this therapy choice is strong, little empirical evidence exists. In order to supplement this literature, retrospective analysis methods are utilized to examine the association of state-, provider-, and patient level characteristics with the prevalence of chronic opioid use in this disease state. Data gathered through this analysis is then used to develop a propensity index for the identification of an appropriate control group for fibromyalgia patients, a task that has proven difficult in the literature to date. Using propensity stratification and matching techniques analysis of the impact of fibromyalgia, chronic opioid use, and the interaction of these two variables are undertaken. Several key findings and updates to the understanding of chronic opioid use and fibromyalgia syndrome are reported. Wide geographic variation in chronic opioid utilization between states is seen. The role of diagnosing provider type in the rate of chronic opioid prescribing is significant and can be aggregated at various levels. Demographic characteristics, comorbid conditions, and concurrent medication use are all important associates of chronic opioid use in fibromyalgia syndrome. Additionally, chronic opioid use in fibromyalgia patients, independent of propensity to receive that therapy choice is a significant correlate with healthcare costs. A diagnosis of fibromyalgia is a statistically significant source of healthcare costs, though the clinical significance of its impact when compared to a closely matched control group is minimized. Despite the minimization of the role of this diagnosis the impact of the interaction of chronic opioid use with fibromyalgia, despite control for myriad regressors, is significant both statistically and clinically.
73

Phenotypic and Genetic Diversity in the Sea Urchin Lytechinus Variegatus

Wise, Maria L. January 2011 (has links)
<p>Diversity in coloration is a common phenomenon in marine invertebrates, although the ecological significance of the diversity is often unknown. Patterns of geographic variability, particularly with respect to color phenotypes, are evident in many organisms and may provide visual evidence of natural selection. </p><p>This dissertation examined the geographic and genetic variability of color patterns and morphology of the sea urchin <italic>Lytechinus variegatus </italic>. This study had 3 objectives: 1) to describe and quantify phenotypic diversity--color and morphology--throughout the geographic range; 2) to determine the heritability of color in genetic crosses between individuals with similar and differing phenotype; 3) to assess the degree of genetic divergence between and within the regions and congruence between the phylogenetic mitochondrial COI data and color phenotypes seen in the field.</p><p>The distribution of color phenotypes in the field is highly variable across the geographic range which stretches from Beaufort NC to southern Brazil and throughout the Gulf of Mexico and Caribbean. Urchins in each of the 5 regions sampled (Beaufort, Gulf, Keys, Panama and Brazil) have a distinct phenotypic composition despite the presence of similar color morphs. The two regions at the extremes--Beaufort and Brazil--demonstrate the most homogeneous phenotypes, each with a single dominant color morph. The Keys has the most heterogeneous composition with all 14 color morphs present. Morphological diversity mirrors color diversity in being highly variable across the range. Urchins in Beaufort are significantly different morphologically from urchins in the central portion of the range, with thicker, flatter tests and longer more robust spines.</p><p>The heritability of color phenotypes and morphology suggests that genes rather than environment have a major role in color phenotype and patterning as well as morphology in test, spines and lanterns. F<sub>1</sub> and F<sub>2</sub> offspring of Beaufort and Tavernier Key crosses resemble the parental phenotypes in both morphology and color phenotype. Hybrids from crosses between regions have a mixed color palette and intermediate morphological characteristics. The crosses establish that in <italic>L. variegatus </italic>the white phenotype is a dominant autosomal trait and green and purple are recessive and co-expressed. Patterning of the test and spines is dominant to non-patterning. </p><p>Analysis of the mitochondrial COI gene in urchins from Beaufort, Gulf and Keys regions revealed two clades. Clade 1 composed exclusively of Keys urchins differed significantly (F<sub>ST</sub> = 0.89, <italic>P</italic> < 0.001) from Clade 2 composed of urchins from Beaufort, Gulf and Keys. Genetic differentiation within Clade 2 was zero, indicating that urchins in these regions are genetically identical. The genetic split between phenotypically indistinguishable Keys urchins suggests cryptic species. Genetic differentiation does not concord with phenotypic and morphological differentiation. No structure was detected with regards to color phenotype in either clade or region of origin in Clade 2.</p> / Dissertation
74

The Mystery of the Chaetognatha: A Molecular Phylogenetic Approach Using Pelagic Chaetognath Species on Pelican Island, Galveston, Texas

Towers, Leah Nicole 2010 December 1900 (has links)
The phylum Chaetognatha is a mysterious group of organisms that has eluded scientists for more than a century because of their unique morphology and developmental characteristics, i.e. protostome (mouth develops from blastopore; e.g. mollusks, annelids, arthropods) versus deuterostome (anus develops from blastopore; e.g. echinoderms and chordates) offer few clues to their evolutionary origins. Some early morphological studies argued that chaetognaths were derived mollusks or nematodes according to gross ultrastructural data, while other studies focused on the coelomic cavity. 33 Although 18S rRNA is widely used in molecular phylogeny studies, it has limits such as long- branch chain attractions and a slow rate of evolutionary change. Long-branch chain attractions are a phenomenon in phylogenetic analyses when rapidly evolving lineages are inferred to be closely related, regardless of their true evolutionary relationships. Hence other genes are used in this study to complement the 18S rRNA such as the cytochrome oxidase genes. The cytochrome oxidase genes are highly conserved throughout all eukaryotic organisms and they are less ambiguous to align as compared to the ribosomal genes, making them better phylogenetic markers as compared to the 18S rRNA gene. This study focuses on using a molecular approach (ARDRA, PCR, phylogenetic tree reconstruction) to determine the phylogeny of pelagic chaetognaths found on Pelican Island, Galveston, Texas. 18S rRNA, Cytochrome Oxidase I and Cytochrome Oxidase II genes were used to help decipher the phylogeny of this group. All analyzed genes in this study (18S rRNA, COI, and COII) grouped the Pelican Island chaetognaths with the protostomes. The maximum parsimony bootstrap tree for the 18S rRNA gene, grouped the samples closest to the arthropods (protostome). For the COI and COII genes, the minimum evolution bootstrap tree grouped the 8 collected samples more closely to two other protostome phyla: the mollusks and annelids (COI) while bootstrapping with the COII grouped the samples with the nematodes (with >66 percent bootstrap). My findings are significant because they reveal phylogenetic results of a protostome lineage for the Chaetognatha using 3 genes, one of which (COII) has not been greatly studied for the Chaetognatha.
75

Φυλογενετικές σχέσεις των αμφιβίων ομάδων ισοπόδων με τα υπόλοιπα ισόποδα

Κούτμος, Θεόδωρος 05 February 2008 (has links)
Τα ισόποδα αποτελούν τη μοναδική τάξη οργανισμών ανάμεσα σε όλα τα Καρκινοειδή που πέτυχε να εποικήσει όλους τους τύπους ενδιαιτημάτων, από τα βάθη των ωκεανών μέχρι τα βουνά, τις έρημους και τις τροπικές περιοχές. Παρόλα αυτά, οι φυλογενετικές σχέσεις εντός της τάξης των ισοπόδων παραμένουν σε πολλά σημεία ασαφείς. Η οικογένεια Tylidae, που περιλαμβάνει 27 αμφίβια είδη, ανήκει σύμφωνα με τη σημερινή συστηματική κατάταξη στην υπόταξη Oniscidea, τη μοναδική που περιλαμβάνει αντιπροσώπους με χερσαίο ή ημι-χερσαίο τύπο διαβίωσης. Αν και υπάρχουν αμφιβολίες ως προς τη μονοφυλετική προέλευση αρκετών από τις 9 υποτάξεις που περιλαμβάνουν θαλάσσιους αντιπροσώπους, η προέλευση των Oniscidea θεωρείται αδιαμφισβήτητα μονοφυλετική. Εντούτοις, δεν υπάρχει ακόμη συμφωνία ως προς την ακριβή τοποθέτηση του κλάδου των Tylidae στο φυλογενετικό δέντρο των Oniscidea. Ο βασικός στόχος της παρούσας εργασίας ήταν ο προσδιορισμός των φυλογενετικών σχέσεων των αμφιβίων ισοπόδων της οικογένειας Tylidae με τα υπόλοιπα ισόποδα, με έμφαση στις σχέσεις με τα υπόλοιπα Oniscidea. Για το σκοπό αυτό χρησιμοποιήθηκαν μοριακοί δείκτες από 14 γένη ισοπόδων, τα οποία αντιπροσωπεύουν όλους τους τύπους διαβίωσης, από τον αποκλειστικά θαλάσσιο έως τον αποκλειστικά χερσαίο. Η πειραματική προσέγγιση περιλάμβανε τον πολλαπλασιασμό αλληλουχιών του πυρηνικού γονίδιου 18s rDNA και των μιτοχονδριακών 16s rDNA και COI με τη μέθοδο της αλυσιδωτής αντίδρασης πολυμέρασης (PCR), τον προσδιορισμό της αλληλουχίας τους και τη φυλογενετική ανάλυσή τους με μεθόδους μέγιστης φειδωλότητας, μέγιστης πιθανοφάνειας και μπεϊεσιανής συμπερασματολογίας. Οι μιτοχονδριακές αλληλουχίες εμφανίζουν πολύ υψηλά ποσοστά νουκλεοτιδικών υποκαταστάσεων, και σε συνδυασμό με τη χαμηλή αξιοπιστία των δέντρων που παράγονται φαίνεται πως έχουν απωλέσει εντελώς το φυλογενετικό τους σήμα. Η αλληλουχία του 18s rDNA έχει μήκος 2400-3400 bp και αποτελείται από 4 συντηρημένες περιοχές και 3 υπερ-μεταβλητές. Για τις φυλογενετικές αναλύσεις χρησιμοποιήθηκαν μόνο οι συντηρημένες περιοχές, που συνιστούν ένα σύνολο 1597 διακριτών χαρακτήρων. Στα αποτελέσματα από όλες τις υπολογιστικές μεθόδους η οικογένεια Tylidae τοποθετείται στο τελικό δέντρο σε αδελφό κλάδο του τάξου Crinochaeta της υπόταξης Oniscidea. Εντούτοις, παρατηρήθηκε πως η οικογένεια Ligiidae τοποθετείται σε κλάδο μη-συγγενικό προς τα υπόλοιπα χερσαία ισόποδα, υπονοώντας πως η υπόταξη Oniscidea δεν είναι μονοφυλετική. Για να ελέγξουμε αυτήν την υπόθεση, χωρίσαμε τα δεδομένα μας σε αλληλουχίες από θαλάσσιους και σε αλληλουχίες από χερσαίους αντιπροσώπους, πραγματοποιώντας ένα σύνολο από πρόσθετες αναλύσεις. Από τα αποτελέσματα φαίνεται πως η υπόταξη Oniscidea είναι μονοφυλετική και η αντίθετη αρχική υπόθεση οφείλεται σε ‘θόρυβο’ στο φυλογενετικό σήμα των συντηρητικών περιοχών του 18s rDNA. Τέλος, από τις πρόσθετες αναλύσεις προκύπτουν, με ισχυρή στατιστική στήριξη, φυλογενετικά δέντρα που υποστηρίζουν τη συστηματική κατάταξη που είχε προτείνει ο Erhard από τις μορφολογικές του μελέτες, τοποθετώντας τα Tylidae εντός του τάξου ‘Holoverticata’. / Isopods comprise a unique order among the Crustaceans that has settled effectively all possible habitats on the planet. The phylogenetic relationships, though, between the 10 suborders remain unresolved, as many of them might prove to be non-monophyletic taxa. The family Tylidae consists of 27 amphibian species and is traditionally classified in the suborder Oniscidea, which includes all the terrestrial and semi-terrestrial isopods and that is thought to be unambiguously monophyletic. However, the previous phylogenetic studies have proposed many hypotheses concerning the relations between the Tylidae and the other Oniscidea, lacking any plausible consensus. In order to resolve those phylogenetic relations, we used two mitochondrial sequences (16s, COI) and one nuclear (18s) from 14 genera of isopods. Our experimental approach included PCR amplification, sequencing and computational phylogenetic analyses by means of maximum parsimony, maximum likelihood and Bayesian inference. The mitochondrial sequences present extreme values of nucleotide substitutions and evident saturation, a fact that prohibits their use in further analyses. The 18s sequences vary significantly in size (2400-3400 bp) and consist of 4 conserved and 3 hyper-variable regions. Only the conserved regions were used for analysis, resulting to a dataset of 1597 discrete nucleotide characters. Regardless of the method used, the family Tylidae appeared as a sister-clade of the taxon Crinochaeta (suborder Oniscidea) in the cladograms. We noticed, though, that the taxon Diplochaeta (Oniscidea: Ligiidae) appeared (with low bootstrap values) in a distant clade of all the other Oniscidea, a result that does not support the monophyletic origin of the Oniscidea. In order to test the validity of this result, we splitted our dataset and conducted additional, separate analyses for the sequences of the marine isopods and those of the terrestrial isopods. Our results indicate that the suborder Oniscidea is monophyletic, so the initial opposite hypothesis was due to weak phylogenetic signal. Finally, our cladograms support, with significant confidence, the systematic classification that Erhard (1998) had proposed through his studies on morphological characters of the Oniscidea, placing together the family Tylidae and the taxon Crinochaeta under the name ‘Holoverticata’.
76

Species identification and discovery in common marine macroalgae: Fucus, Porphyra and Ulva using a DNA barcoding approach.

Hana, Kucera January 2010 (has links)
The oceans represent a wealth of biological diversity where many species remain to be discovered and described. Among seaweeds, a paucity of morphological features by which to differentiate species means that many genera harbour overlooked or cryptic species. Fucus, Porphyra and Ulva are three common genera of marine intertidal algae and all include species that are particularly difficult to distinguish morphologically. DNA barcoding has been championed as a revolutionary tool for species identification and discovery and applying this tool to algae was a logical step due to the difficulty of morphological identification of many algal species. This thesis is part of a significant initiative aimed at identification and discovery of all species of seaweeds in Canadian waters, using a DNA barcoding approach. The original concept of DNA barcoding relied on comparing the 5’ region of the mitochondrial cytochrome c oxidase 1 (COI-5P) gene among animal species. In this study, DNA barcoding with COI-5P was applied to the brown algal genus Fucus and worked as well as any other marker to assign morphologies to known species. The DNA barcoding results also uncovered substantial phenotypic diversity in Pacific F. distichus. Results were confirmed by comparison with sequences of the nuclear internal transcribed spacer region (ITS). For Porphyra, COI-5P DNA barcoding was compared with species identification using the chloroplast large rubisco subunit (rbcL) and the Universal Plastid Amplicon (UPA) in a floristic survey of Canadian Porphyra species. Two new species were discovered and described (Porphyra corallicola and Porphyra peggicovensis), and P. cuneiformis was synonymized with P. amplissima. The COI-5P emerged as the best marker for species discrimination despite difficulties with primer universality. To aid in choosing a marker for DNA barcoding for green algae, the universality and species discriminatory power of the rubisco large subunit (rbcL) (considering the 5’ and 3’ fragments independently), the UPA, the D2/D3 region of the nuclear large ribosomal subunit (LSU-D2/D3) and the ITS were evaluated. While the rbcL-3P highlighted several cryptic species, and worked well to distinguish Ulva species, more research is needed to recommend a marker for DNA barcoding generally in marine green macroalgae.
77

Phylogeography of Darlingtonea Kentuckensis and Molecular Systematics of Kentucky Cave Trechines

Boyd, Olivia Frances 01 May 2015 (has links)
The monotypic cave carabid genus Darlingtonea is widely distributed along the eastern band of the Mississippian/Pennyroyal plateau in Kentucky and northern Tennessee. DNA sequence data from the mitochondrial gene cytochrome oxidase subunit I (COI) was collected from one to four individuals from 27 populations, and patterns of phylogeography and population structure were inferred from COI haplotypes. A hierarchical analysis of molecular variance found low nucleotide diversity within populations and statistically significant variation among geographically-defined groups tested based on two a priori hypotheses of structure. Population structure among five distinct genetic clusters identifies approximate locations of barriers to gene flow among closely grouped caves in the upper Rockcastle River drainage. Partial sequences of one mitochondrial (COI) and one nuclear (wingless) gene were gathered from 60 to 106 terminal taxa, including representatives of all five genera of cave trechines from Kentucky and Tennessee. Alignments were analyzed using maximum parsimony, Bayesian, and maximum likelihood methods of phylogenetic inference. Comparison of analyses demonstrates conflicting tree topologies among individual markers and different reconstruction methods. Despite a lack of consensus regarding genus-level relationships, most analyses supported each genus as natural (monophyletic) with the exception of Pseudanophthalmus
78

Connectivity within a metapopulation of the foundation species, Ridgeia piscesae Jones (Annelida, Siboglinidae), from the Endeavour Hydrothermal Vents Marine Protected Area on the Juan de Fuca Ridge

Puetz, Lara 30 April 2014 (has links)
The natural instability of hydrothermal vents creates variable environmental conditions among habitat patches. Habitat differences correspond to phenotypic variation in Ridgeia piscesae, the only ‘vent tubeworm’ on the spreading ridges of the Northeast Pacific. Ridgeia piscesae that occupy high fluid flux habitats have rapid growth rates and high reproductive output compared to tubeworms in habitats with low rates of venting fluid delivery. As recruitment occurs in all settings, worms in the “optimal habitat” may act as source populations for all habitat types. Ridgeia piscesae is a foundation species in the Endeavour Hydrothermal Vents Marine Protected Area of the Juan de Fuca Ridge. The objective of this thesis was to assess fine scale population structure in Ridgeia piscesae within the Endeavour vent system using genetic data. Population structure was assessed by analysis of the mitochondrial COI gene in 498 individuals collected from three vent sites of the Juan de Fuca Ridge; Middle Valley (n=26), Endeavour Segment (n=444) and Axial Volcano (n=28). Genotyping using microsatellite markers was attempted but all loci developed for closely related tubeworm species failed to amplify microsatellites in Ridgeia piscesae. Sequence analysis identified 32 mitochondrial COI haplotypes; one dominant haplotype (68%), three common haplotypes (4%-7%) and the remainder were rare (<2%). Axial Volcano was differentiated from Middle Valley and Endeavour. Within Endeavour, genetic sub-structuring of Ridgeia piscesae occurred among vent fields (Clam Bed, Main Endeavour and Mothra) and habitat types < 10 km apart. Patterns of genetic variation and coalescent based models suggested that gene flow among vent fields moved in a north to south direction in individuals from high flux habitat but from south to north in individuals from low flux habitat. Tubeworms from low flux habitat had more nucleotide polymorphisms and haplotypes than those from high flux habitats. Estimates of the number of immigrants per generation moving from high flux to low flux subpopulations was four times higher than in the reverse direction. The effective population size was estimated to be three times greater in high flux habitat when the generation times for individuals from each habitat type were considered. Demographic tests for population equilibrium identified a recent and rapidly expanding metapopulation at Endeavour. Models of gene flow in Ridgeia piscesae reflected the general oceanographic circulation described at Endeavour. Genetic data illustrate that dispersing larvae exploit the bi-directional currents created through plume driven circulation within the Endeavour axial valley and suggest that adult position on or near chimneys may influence larval dispersal trajectories upon release. Building on known ecological and biological features, this study also showed that Ridgeia piscesae from limited and ephemeral high flux habitat act as sources to the overall metapopulation and that asymmetrical migration and habitat stability sustain high genetic diversity in low flux sinks. The overall metapopulation at Endeavour experiences frequent extinction and recolonization events, differences in individual reproductive success, and source-sink dynamics that decrease the overall effective size and genetic diversity within the population. These factors have important implications for the conservation of a foundation species. / Graduate / 0307 / 0329 / 0369 / lcpuetz@uvic.ca
79

Population structure and genetic diversity of Southeast Queensland populations of the Wallum Froglet, Crinia Tinnula (Tschudi)

Renwick, Juanita January 2006 (has links)
Genetic diversity is a fundamental attribute that contributes to a species evolutionary survival. In recent times, conservation managers have recognized the need to preserve genetic diversity of declining species, and have also acknowledged the utility of genetic markers for describing genetic and ecological relationships within and among populations. Information obtained from genetic studies can be used in conjunction with information on population demography, land use patterns and habitat distribution to develop effective management strategies for the conservation of species in decline. The wallum froglet, Crinia tinnula, is one of Australia's smallest habitat specialist anurans. In recent years there has been a dramatic decrease in population numbers of this species. The habitat to which C.tinnula is endemic ('wallum' habitat) is restricted to low coastal plains along the southeast Queensland and northern New South Wales coastline. As human populations in this region expanded, the coastal areas have undergone significant development and large areas of wallum habitat have been cleared. The effect has been to convert once largely continuous patches of coastal heathland in to a matrix of small habitat patches within an area undergoing rapid urban expansion. This study aimed to document levels and patterns of genetic diversity and to define the population structure of C.tinnula populations within southeast Queensland, with the objective of defining possible conservation management units for this species. Results from 12S and COI mitochondrial markers clearly showed that two distinct evolutionary lineages of C.tinnula are present within southeast Queensland. The high level of divergence between lineages and strict geographic partitioning suggests long term isolation of C.tinnula populations. It is hypothesized that ancestral C.tinnula populations were once confined to wallum habitat refugia during the Pliocene resulting in phylogeographic delineation of 'northern' and 'southern' C.tinnula clades. Populations within each geographic region show evidence of range contraction and expansion, with subsequent restricted gene flow. Levels of genetic diversity appear, largely, to be the product of historical associations rather than contemporary gene flow. A revision of the current systematics of C.tinnula is required to ensure that discrete population groups are recognized as distinct evolutionary lineages and will therefore be protected accordingly.
80

Análise dos genes mitocondriais COI e 16S de populações de Chrysoperla externa (Hagen, 1861) (Neuroptera: Chrysopidae) de diferentes localidades geográficas

Baggio, Mariah Valente [UNESP] 24 February 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-02-24Bitstream added on 2014-06-13T18:26:17Z : No. of bitstreams: 1 baggio_mv_me_jabo.pdf: 512063 bytes, checksum: 11244a431e6c0f8cc5195b1c7d20e1bd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Chrysoperla externa é uma espécie de crisopídeo encontrada em diversos agroecossistemas brasileiros, capaz de se alimentar de diferentes pragas agrícolas. Em cada ambiente em que for encontrada poderá sofrer diferentes pressões seletivas do ambiente. Para a verificação das mutações genéticas presentes nas populações de C. externa podem ser usados marcadores moleculares, em especial os genes mitocondriais, que são de fácil manipulação. C. externa é de fácil criação e a mais estudada para multiplicação massal, por isso se faz necessário estudar a resposta das populações quando liberadas em ambientes diferentes, visto que estas podem não sobreviver em áreas biogeográficas distintas, inviabilizando o seu papel como agente de controle de pragas. O objetivo deste trabalho foi caracterizar geneticamente as populações de C. externa nos municípios de Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) e São Sebastião do Paraíso (MG). Para o gene COI foram verificados oito haplótipos, seis mutações e a maior diversidade haplotípica foi encontrada em Brotas e São Sebastião do Paraíso. Para o gene 16S foram observadas quatro mutações, seis haplótipos e a maior diversidade haplotípica ocorreu no município de São Sebastião do Paraíso. A distância genética encontrada entre as populações de C. externa não foi significativa para os dois genes analisados, evidenciando que provavelmente as populações são geneticamente compatíveis. O estudo da estrutura genética dessas populações de C. externa, de ambos os genes, mostrou que essas populações não apresentam um padrão de distribuição haplotípica. Então, talvez sejam necessários outros estudos com populações desta espécie oriundas de localidades mais distantes geograficamente dos que as utilizadas neste trabalho / Chrysoperla externa is a species of green lacewing found in several Brazilian agroecosystems able to feed on various agricultural pests. In each environment that is found may experience different environmental selective pressures. In order to verify genetic mutations in C. externa populations it may be used molecular markers, in particular mitochondrial genes, which are easy handling and extraction. C. externa is easy to create and the most studied for mass multiplication, so it is necessary to study on the response of populations when released in different environments, since they may not survive in different biogeographic areas, derailing its role as a pest controller. The objective of this study was to characterize genetically the populations of C. externa from the cities of Brotas (SP), Jaboticabal (SP), Rifaina (SP), São Carlos (SP), São José dos Campos (SP) and São Sebastião do Paraíso (MG). For the COI gene it was found eight haplotypes, six mutations and greater haplotype diversity in Brotas and São Sebastião do Paraíso. In the 16S there were four mutations, six haplotypes and haplotype diversity was higher in São Sebastião do Paraíso. The genetic distance among populations of C. externa was not significant for the two genes analyzed, showing that the populations are probably genetically compatible. The study of the genetic structure of populations of C. externa, showed for both genes that these populations do not show a pattern of haplotype distribution. So, it may need further study on populations of this species originating from geographically more distant locations of those used in this work

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