The eastern subterranean termite, Reticulitermes flavipes, is the most widely dispersed termite in North America. The genus Reticulitermes spp. is responsible for 80% of total termite damage caused to urban structures each year. Little is known about the genetic structure of termites, particularly at the colony level. Evidence for what genetically defines a termite colony is a hotly debated topic in current literature due to the implications such findings would have regarding current lawsuits against pest control operations. Information on termite genetic structure is sparse. In this study, the genetic variation and gene flow among Texas populations of R. flavipes at the statewide level and city level was examined. A 324-337 base pairs segment of the mtDNA, AT-rich region was a polymerase chain reaction amplified from 104 different termite specimens from 12 Texas cities. The DNA extracts were then subjected to PCR amplification using specific primers and it was then sequenced. Using the sequence data and appropriate statistical measures it was found that, at the statewide level, nucleotide and haplotypic diversity is low. Gene flow was found to be low on a statewide basis. At the city level nucleotide and haplotypic diversity was high. The findings of this study provide insights into termite genetic structure.

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A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfillment of the requirements for the Degree of Doctor of Philosophy. / Y chromosome DNA and mitochondrial DNA (mtDNA) variation were examined in Ugandans, Zambians, Biaka Pygmies and non-Pygmies from the Central African Republic. Y chromosome DNA variation was also examined in populations from the Democratic Republic of Congo. Data generated in this study were analysed together with published data to (1) clarify the understanding of the overall patterns of haploid genetic variation in Africa; (2) examine genetic affinities among central African and other African populations; (3) assess the concordance of haploid markers with different mutation rates in assessing population affinities; (4) compare male and female migration rates in African populations; and (5) refine theories regarding the prehistory of central Africa populations based on linguistics and archaeology. Sixteen biallelic and eight microsatellite Y-specific markers were examined in 369 central African individuals. Eleven Y chromosome haplogroups (HGs A, B*, B-M150, B-Ml 12, B- M211, E-M191, E-M2, E-M35, E-M40, FJ and R) and 174 compound haplotypes were identified. The mtDNA 9-bp deletion, 3592 Hpal and 10397 Alul restriction polymorphisms, and two hypervariable regions (HVRs) were examined in 397 individuals. A total of 246 mtDNA types were identified and classified into 19 mtDNA subhaplogroups. Using Y chromosome data, central African populations shared close genetic affinities with each other and with populations from west and southern Africa. Extensive unidirectional Y chromosome gene flow from non-Pygmy populations to Biaka Pygmies was observed. Using mtDNA data, central African non-Pygmy populations shared close genetic affinities with each other and with populations from west, east and southern Africa. MtDNA studies indicated almost complete maternal genetic isolation of Biaka. Overall, using both mtDNA and Y chromosome data, pan-African populations were best grouped by geographic rather than by linguistic criteria. Different mtDNA and Y chromosome data types revealed similar genetic relationships among African populations. Female migration rates appear to have exceeded male migration rates in non-Pygmy central African populations in this study, whilst the opposite was found in Biaka Pygmies. Data types at different levels of resolution suggested that male and female migration rates in Africa may have differed over time, and may not have been significantly different. This research has provided new insights into the complex demographic history that shaped the present-day genetic landscape of central African populations. / WHSLYP2016

Population genetic variation of cultured oyster Crassostrea spp. in Taiwan and neighborhood Cheng-Pin Yu ¡]Advisor¡GDr. Jin-Hua Cheng¡^ Institute of Marine Biology, National Sun Yat-sen University, Kaohsuang 804 Taiwan R.O.C. Thesis Abstract The genetic variations among oyster populations of Taiwan, Ginmen and Fu-kein coast are analyzed using molecular method. Firstly, DNA sequences of mitochondrial 16S rRNA and COI genes are analyzed according to nucleotide differences and restriction enzyme recognition site. Then, population variations were analyzed by the lane pattern of restriction enzyme fragment¡]RFLP¡^. The sequences of 530 bp DNA fragment of 16S rRNA gene showed little difference¡]0-1 bp¡^between Portuguese oyster and oyster cultured in Taiwan, both have larger differences¡]3-4 bp¡^compared with C. gigas. The sequences of 700 bp DNA fragment of COI gene showed similar results. C. angulata is found in Ginmen and Fu-kein coast for the first time which is identified by the PCR-RFLP of COI gene fragment. PCR-RFLP analysis of COI gene fragment showed C. angulata from Portugal are genetically closest to the oysters collected from Ginmen and Fu-kein.

Environmental variation of Thamnocortus insignis Mast. (Restionaceae) is presented, by using average dry weight measurements of six populations of this species found along the coast of the Cape Province. The dry weight measurements were used to detect variation in the growth rates of the six populations, which in tum indicates the environmental variation among the populations. The results were showed no significant difference between all six populations and this was due to the relatively very small sizes of the seedlings when the measurements were taken. Genetic variation was investigated by using isozyme electrophoresis of the EST locus. One population (Puntjie) showed significant deviation from the Hardy-Weinberg equilibrium, whilst all the others agreed with the assumptions of the model except for the Superthatch-extra tall population, which was homologous. Estimation of allelic diversity among the populations produced a Fst of 0.098 that implies that there is a high level of gene flow among the six populations of the species. The allelic diversity estimate within populations was also very low (Fis = 0.079) implying that the genetic neighbourhoods are relatively large and there is a high incidence of gene flow within the populations. Both estimation results support the predicted results for dioecious wind-pollinated species such as T. insignis.