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Bibliography: leaves 106-120.
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| Format: | Thesis |
| Language: | English |
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Department of Biological Sciences
2014
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| _version_ | 1867613214478434305 |
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| access_status_str | Open Access |
| author | Mapaya, Ruvimbo Jessy |
| author2 | Hedderson, Terry A |
| author_browse | Hedderson, Terry A Mapaya, Ruvimbo Jessy |
| author_facet | Hedderson, Terry A Mapaya, Ruvimbo Jessy |
| author_sort | Mapaya, Ruvimbo Jessy |
| collection | Thesis |
| description | Bibliography: leaves 106-120. |
| format | Thesis |
| id | oai:open.uct.ac.za:11427/6131 |
| institution | University of Cape Town (South Africa) |
| language | eng |
| last_indexed | 2026-06-10T12:32:34.479Z |
| license_str | Not specified — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository |
| publishDate | 2014 |
| publishDateRange | 2014 |
| publishDateSort | 2014 |
| publisher | Department of Biological Sciences |
| publisherStr | Department of Biological Sciences |
| record_format | dspace |
| source_str | UCTD — University of Cape Town Open Access Repository |
| spelling | oai:open.uct.ac.za:11427/6131 Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives Mapaya, Ruvimbo Jessy Hedderson, Terry A Bruyns, Peter V Systematics and Biodiversity Sciences Bibliography: leaves 106-120. The genus Euphorbia is morphologically diverse and nearly cosmopolitan. Both succulent and non-succulent species are found within the genus. Succulent species are found in most arid and semi-arid areas of the world, but show their greatest concentration and diversity of form in Southern Africa especially the Cape Floristic Region. The monophyly and phylogenetic relationships of the genus Euphorbia were investigated based on morphology and on sequences of the nuclear ribosomal internal transcribed spacer (ITS) and chloroplast psbA-trnH intergenic spacer. Fifty-one species of Euphorbia and four outgroups from Monadenium and Ciutia were sampled. Matrices were analysed using parsimony and maximum likelihood methods. Separate analyses of data partitions resulted in largely non-conflicting topologies; therefore the data sets were combined. The results showed that the genus Euphorbia is paraphyletic and four monophyletic groups with a number of putative synapomorphies defining each clade were strongly supported in most analyses. The Cape succulents fall into two well-supported clades. The results thus provided evidence for Cape radiations. Most analyses indicated that one of the Cape groups is sister to a group consisting of species mostly from Southern Africa (excludingthe Cape Region). Increased taxon sampling is however needed to clarify relationships within the monophyletic groups. Morphological characters recovered broad groups within Euphorbia. Due to inadequate sampling in some sections, modifications in the present classification of Euphorbia are not suggested. The total evidence tree was used to explore morphological character evolution through character state optimisations. The presence of root tubers was homoplasious and this character state is hypothesized to have arisen at least five times under current sampling. Cylindrical stems, conspicuous leaves and absence of leaf spines were some of the pleisiomorphic states observed in some sampled members of the genus Euphorbia. Although the results obtained in the CUlTent study are preliminary, they have created further challenges for future studies of phylogenetic relationships and morphological character evolution in the genus Euphorbia. 2014-08-13T14:05:08Z 2014-08-13T14:05:08Z 2003 Master Thesis Masters MSc http://hdl.handle.net/11427/6131 eng application/pdf Department of Biological Sciences Faculty of Science University of Cape Town |
| spellingShingle | Systematics and Biodiversity Sciences Mapaya, Ruvimbo Jessy Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| thesis_degree_str | Master's |
| title | Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| title_full | Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| title_fullStr | Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| title_full_unstemmed | Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| title_short | Molecular and morphological phylogenetic analyses of Euphorbia L. (Euphorbiaceae) with an emphasis on Southern African representatives |
| title_sort | molecular and morphological phylogenetic analyses of euphorbia l euphorbiaceae with an emphasis on southern african representatives |
| topic | Systematics and Biodiversity Sciences |
| url | http://hdl.handle.net/11427/6131 |
| work_keys_str_mv | AT mapayaruvimbojessy molecularandmorphologicalphylogeneticanalysesofeuphorbialeuphorbiaceaewithanemphasisonsouthernafricanrepresentatives |