Rhipicephalus microplus belongs to the Ixodidae, the largest family of ticks, which are of great economic importance due to their negative socio-economic impact on agriculture (BROUQUI 2011; PORTO NETOA et al. 2011; SONENSHINE 1991). Acaricides have been the first choice in tick control for cattle farmers, but R. microplus rapidly acquires resistance to these chemicals. Replication slippage and recombination drive genetic diversity in tick populations (BAFFI et al. 2007; GUERRERO et al. 2007; LI et al. 2007); generating point mutations and frame shifts within the genes targeted by acaricides, resulting in resistance (BAFFI et al. 2007; HERNANDEZ et al. 2002; HERNANDEZ et al. 2000; JONSSON et al. 2010; MORGAN et al. 2009). In addition, resistance can quickly accumulate in a population due to the pangamy mating structure of ticks (CHEVILLON et al. 2007b; CUTULLÉ et al. 2010) and their ability to produce multiple generations within one season (BUDELI et al. 2009; LI et al. 2007). Vaccines have become increasingly important to control ticks, as acaricide resistance can be acquired by field tick populations within two years (RODRIGUEZ-VIVAS et al. 2011). Although Bm86 has been successful against multiple-acaricide resistant ticks, recent reports indicate that the Bm86 vaccine has become ineffective, possibly due to resistance (PARIZI et al. 2009). Also, Bm86 vaccines display great variability in terms of their efficacy against ticks isolated across Argentina (GARCIA-GARCIA et al. 2000; PARIZI et al. 2009). This is hypothesised to be due to the genetic variability between R. micoplus populations. The majority of phylogenetic studies on ticks have been based on slow evolving sequences, such as 18S or 28S rRNA, which provide genus-level resolution. The COI, D3, ANT and ITS2 genes have the potential to resolve intra-specific and interspecies variation, and may assist with the identification of cryptic speciation within R. microplus of South Africa (ANSTEAD et al. 2011; BARKER 1998; CAREW et al. 2009; MURRELL et al. 2000; SONGA et al. 2011). Phylogeography is a multidisciplinary field that utilises phylogenetic (molecular evidence of speciation) and population genetic principles (coalescence theory), in combination with additional data (such as geography and population history), to determine the genetic relationships of populations within a species (AVISE 2009) and was one of the main aspects of this study. The phylogenetic and population genetic structure of R. microplus will provide valuable information to geneticists, farmers and acaricide/vaccine suppliers about the different R. microplus tick populations of South Africa. The information will facilitate more efficient and targeted tick control whether acaricide or vaccine based as opposed to the inefficient approaches generally adopted to tick control. / Dissertation (MSc)--University of Pretoria, 2014. / lk2014 / Genetics / MSc / Unrestricted

Two and a half years of data were collected from the Great Fish River and estuary using seine nets and gill nets to determine the fish species composition within these regions. The head region of the Great Fish River estuary was found to have a rich fish fauna, with the euryhaline marine fish component totally dominating the catch in all three regions. Gilchristella aesiuaria was the single most common species and several euryhaline marine species were captured in freshwater for the first time. Physical parameters were also measured in an effort to ascertain the possible factors which may affect the distribution and length frequency of the most common species within this area. Salinity was found to be the single most important factor affecting the species composition, and the sampling area was consequently divided into three regions, viz. river (< I ‰), head (1-4 ‰) and estuary (> 4 ‰). In addition, it was determined that river flow rate during the month prior to sampling also had a profound effect on species composition in all three regions. Based on the available evidence it is suggested that for most species this is related to conductivity levels rather than flow per se.

The greater kudu (Tragelaphus strepsiceros) is a large spiral-horned antelope that occurs in sub-Saharan Africa. The species is predominantly a browser and inhabits a diverse range of habitats including savanna woodland, scrub and open forests. The geographical distribution extends from south-eastern Chad, northern Central African Republic (CAR), through eastern Africa, to southern Africa. Throughout its range the species is threatened by habitat loss, fragmentation, diseases and hunting for trophy. Consequently, many populations have reduced numbers and are at great risk of local extinction. In the absence of evidence from comprehensive studies, strategies for conservation and management of many species are often based on subspecies designations despite the fact that the original descriptions were based on few samples and morphological characters that vary extensively. To develop appropriate conservation and management measures, it is imperative to obtain information on population structure, historical demography and evolutionary history of the species. The information generated is used to define units for conservation of the species. In this study, the objective was to investigate population structure and evolutionary history of the greater kudu by analysing mitochondrial DNA (mtDNA) control region sequences and examining size variation in eight microsatellite loci. The mtDNA control region sequences were examined using a combined approach that included phylogeographic, nested clade and mismatch frequency distribution analyses. It was anticipated that use of the two types of genetic markers with contrasting patterns of inheritance and mutation would enhance the understanding and interpretation of the evolutionary history of the species throughout its range. The results were used to evaluate subspecies taxonomy, draw inferences on historical demography and provide information relevant for conservation and management of T. strepsiceros. Intraspecific variation in the mtDNA was examined in 94 samples from 12 locations and revealed low to medium levels of nucleotide diversity. The average nucleotide diversity was 2.7% (0.3% to 2.9%). The average sequence divergence between populations was 2.3% (0.0% to 5.7%). Eight microsatellite loci were analysed in 203 samples representing 13 locations. The number of alleles scored from these loci was 7-12 while the mean heterozygosity was 70.4% (66% to 76%). Microsatellite data showed shallow phylogeographic structure and the average measure of genetic differentiation <1>ST was 0.046. Comparisons of allelic variation across all populations revealed that the Eastern Cape had lower allelic diversity and showed significant differences in allele frequency distribution suggesting a genetic bottleneck in the population's evolutionary past. The combined analyses suggest that the greater kudu originated from Namibia and spread southwards before colonising other parts of its modern range. The results revealed weak geographic partitioning at the regional level, but showed two genetically distinct groups at the continental level. The first group comprised of populations from Namibia, Kimberley and the Eastern Cape from South Africa, while the second comprised of the remaining populations. The results suggest a single evolutionary significant unit (ESU) with two management units (MUs). In the long term, conservation efforts should focus on maintaining demographic connectivity over broad geographical areas within each MU in order to approximate the natural dispersal patterns of the species. / Thesis (PhD (Zoology))--University of Pretoria, 2005. / Zoology and Entomology / unrestricted

Orientadores: Fernando Roberto Martins, Lucia Garcez Lohmann / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-22T05:17:40Z (GMT). No. of bitstreams: 1 Rochelle_AndreLuisCasarin_D.pdf: 2530968 bytes, checksum: 4125ca228d54cbb9e8ca94ccbb3965ff (MD5) Previous issue date: 2013 / Resumo: Integramos biogeografia, ecologia, filogenia e evolução da tribo Bignonieae (Bignoniaceae) para testar as seguintes hipóteses: (1) a área de distribuição geográfica das espécies é positivamente relacionada com sua idade filogenética, conhecida como "hipótese da idade e área", formulada por J.C. Willis, em 1922 que prevê que espécies antigas ocupariam maiores áreas de distribuição enquanto espécies recentes ocupariam menores áreas (endêmicas); (2) área de distribuição geográfica das espécies é positivamente relacionada com o potencial de dispersão anemocórico das sementes; e (3) o potencial de dispersão anemocórico é negativamente relacionado com a idade filogenética das espécies. Realizamos experimentos em túnel de vento para mensurar o potencial de dispersão anemocórico das sementes medindo sua distância de voo (SFD) e investigamos sua relação com oito atributos morfológicos biomecânicos - tamanho total (STS), tamanho do núcleo seminal (SNS), tamanho das alas (SWS), massa (SM), área (SA), razão entre tamanho do núcleo seminal e tamanho da asa (SNS/SWS), razão entre massa e tamanho da asa (SM/SWS) e razão entre massa e área (SM/SA). Analisamos a relação entre as características biomecânicas das sementes responsáveis por um maior potencial de dispersão com a idade filogenética das espécies e sua distribuição geográfica para investigar a evolução dos caracteres relacionados à maior habilidade de dispersão. Realizamos experimentos para verificar diferenças na morfologia e no potencial de dispersão das sementes de herbário em comparação com sementes coletadas em campo, visando validar estudos com sementes herborizadas. Não encontramos relação entre idade filogenética e área de distribuição. Esta relação parece ser influenciada pela diferença na eficiência de dispersão das espécies, apontada como um importante fator na distribuição, especialmente em espécies anemocóricas. 83% das espécies apresentaram correlação entre variáveis morfológicas e SFD. A razão SM/SA apresentou a maior correlação com SFD (36 espécies). SWS e SA apresentaram correlação positiva com SFD. SNS/SWS e SM/SA apresentaram correlações negativas com SFD, demonstrando que características morfológicas das sementes influenciam seu potencial de dispersão, principalmente massa e área. SFD apresentou correlação positiva com área de distribuição e negativa com idade. SNS apresentou correlação positiva com idade. SM/SA apresentou correlação positiva com idade e negativa com área de distribuição. Os resultados mostraram que espécies com sementes de maiores capacidades de voo possuem maiores áreas de distribuição e são mais recentes, evidenciando uma possível seleção no sentido da redução do núcleo seminal que diminuiu a massa das sementes e consequentemente reduziu a razão massa/área, aumentando a capacidade de voo e o potencial de dispersão da espécie. Inferimos que características morfológicas biomecânicas podem ter sido selecionadas no sentido de aprimorar o potencial de dispersão das sementes, principalmente na combinação entre sua massa e área, favorecendo as espécies mais jovens, possibilitando uma dispersão mais eficiente e a expansão da sua distribuição. Complementarmente, demonstramos que o processo de herborização não afeta significativamente os caracteres morfológicos e a distância de voo das sementes, validando os dados gerados pelo nosso experimento. Conhecimentos sobre distribuição de espécies são importantes para a conservação na região tropical onde a megadiversidade é composta majoritariamente por espécies endêmicas / Abstract: We integrated biogeography, ecology, phylogeny and evolution of the tribe Bignonieae (Bignoniaceae) to test the hypothesis that: (1) geographic range size is positively related with species phylogenetic age - the "Age and Area Hypothesis" - formulated by J.C. Willis (1922) and which states that older species would have larger geographic range sizes because they had more time to disperse while younger species would have smaller geographic range sizes; (2) range size is positively related with seed wind dispersal potential; and (3) wind dispersal potential is negatively correlated with species age. We used a wind tunnel to experimentally measure the seed wind dispersal potential measuring the seed flight distance (SFD). We analyzed the correlations of SFD with: seed total size (STS), seminal nucleus size (SNS), seed wing size (SWS), seed mass (SM), seed area (SA), ratio SNS/SWS, ratio SM/SWS, and ratio SM/SA. We analyzed the correlations between seed morphological traits related to wind dispersal potential with species phylogenetic age and their extant geographic range size to investigate a possible evolution of the traits related to an improved dispersal. We conducted an experiment to check if there are significant changes in morphology and flight potential in anemochoric seeds before and after herborization, aiming to validate experiments realized with herbarium seeds. We found no correlation between species phylogenetic age and their geographic distribution area. This relationship found for other taxonomic groups could have been affected here by species dispersal ability, which is an important driver of geographic distribution, especially in wind-dispersed species. 83% of the species had at least one variable correlating with SFD. Ratio SM/SA showed correlation with SFD in 36 species. Considering all the species together, SWS and SA showed positive correlation with SFD. Ratios SNS/SWS and SM/SA showed negative correlations with SFD. Results showed that seed morphological traits are correlated with wind dispersal potential, especially seed mass and area. Seed dispersal distance was positively correlated with the extant geographic range size, and negatively correlated with species phylogenetic age. SNS showed positive correlation with age, and ratio SM/SA showed positive correlation with age and negative correlation with geographic range size. Results indicate that species that have seeds with higher flight capacities are more recent phylogenetically and have larger geographic range sizes. It suggests a selection towards the reduction of the SNS, which reduced the seed mass and therefore their ratio SM/SA, increasing their flight ability and colonizing potential. We infer that some seed morphological traits may have been selected in order to improve seed dispersal potential, especially in the trade-off between seed mass and seed area. Therefore, it benefited younger species enabling them to disperse over larger areas in less time. Complementarily, we showed that herborization does not significantly affect seed morphological traits neither their flight distance, validating the data generated with experiments realized with Bignonieae herbarium seeds. Knowledge about the factors that shape species distribution is important for conservation, especially for the tropical region where the megadiversity is composed in most part by species with small distribution areas (endemics) / Doutorado / Biologia Vegetal / Doutor em Biologia Vegetal

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Original print version missing pages 130-133 (appendix B and Appendix C)

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Small mammal surveys were conducted in two geographically separated aspen areas, in the Chicken Creek Watershed Management Unit, Utah, and Break Neck Flat, Wyoming. Four small mammal species, Peromyscus maniculatus, Clethrionomys gapperi, Zapus princeps and Eutamias minimus were caught most often in both areas of the aspen ecosystem. Peromyscus maniculatus was usually the most abundant animal trapped at all locations indicating the success of this species in aspen communities. The proportion of each species trapped, however, fluctuated, likely in accordance with responses to periodic biotic and abiotic factors. This data will serve as baseline information for the U.S. Forest Service who are going to manipulate the aspen communities by burning in Wyoming and clear-cutting in Utah.

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