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Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity

Dissertation (MSc)--University of Pretoria, 2018.

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Other Authors: Cowan, Don A.
Format: Thesis
Language:English
Published: University of Pretoria 2018
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access_status_str Open Access
author2 Cowan, Don A.
author_browse Cowan, Don A.
author_facet Cowan, Don A.
collection Thesis
dc_rights_str_mv © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc)--University of Pretoria, 2018.
format Thesis
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institution University of Pretoria (South Africa)
language English
last_indexed 2026-06-10T12:37:00.236Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2018
publishDateRange 2018
publishDateSort 2018
publisher University of Pretoria
publisherStr University of Pretoria
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source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/67137 Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity Cowan, Don A. baxterjrose@gmail.com Hogg, Ian D. Baxter, Janine Rose DNA barcoding Redundancy analysis Namib desert Collembola UCTD Dissertation (MSc)--University of Pretoria, 2018. Desert environments are characterised by harsh conditions and possess low biodiversity largely caused by abiotic factors such as; low precipitation, soil organic matter, high temperatures, high levels of evapo-transpiration, pH and salinity. These factors significantly reduce primary production, which influences the availability of food resources for deserts organisms. The diversity and the drivers of diversity for below ground invertebrates including Collembola (springtails) are relatively unknown in the Namib Desert. Previous morphological studies have found only five species on the basis of traditional taxonomy. This study assesses the diversity of Namib Desert Collembola and determines the effect of environmental parameters on this diversity, The diversity of Namib Desert Collembola was assessed using DNA Barcoding. The sequence information of the 178 Collembola specimens, taken from mitochondrial barcoding using the Cytochrome-c oxidase subunit I (COI) gene, was analyzed and Molecular Operational Taxonomic Units (MOTUs) were defined. Collembola community responses to soil physicochemical properties were investigated by using Redundancy Analysis (RDA). MOTUs were successfully indentified to family level (Isotomidae, Neanuridae and Sminthuridae). The researcher found a total of 30 MOTUs, most of which showed limited geographical localisation. The mtDNA COI (barcode) locus revealed high levels of previously unreported genetic diversity of Collembola in the Namib Desert. The RDA indicated that none of the soil physicochemical properties significantly drove variation in Collembola community composition. However, total soil nitrogen was shown to be a strong but not significant driver of variation in community composition (p<0,054). The taxonomic identification of the Collembola specimens was also attempted using traditional morphological analysis. A total of 23 individuals, collected from pitfall traps or extracted from soil samples, were selected for identification. Available European keys were used for identification to genus level where possible. A total eight of specimens were identified to genus level (Folsomides sp), 14 to family level (Entomobryidae) and one to order level (Symphypleona). Both Symphypleona and Entomobryidae were previously unreported from the Namib Desert. The Folsomides genus and the family Entomobryidae were the most abundant groups. This research suggests that soil dwelling Collembola in the Namib Desert have a much higher level of diversity than previously known. However, the study also highlighted the need for a more comprehensive database for Namib Collembola that includes COI sequence data as well as the morphological identification of species. National Research Foundation (NRF) Genetics MSc Unrestricted 2018-11-02T08:59:32Z 2018-11-02T08:59:32Z 2018 2018 Dissertation Baxter, JR 2018, Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity, MSc Dissertation, University of Pretoria, Pretoria, viewed yymmdd <http://hdl.handle.net/2263/67137> S2018 http://hdl.handle.net/2263/67137 en © 2017 University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle DNA barcoding
Redundancy analysis
Namib desert
Collembola
UCTD
Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title_full Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title_fullStr Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title_full_unstemmed Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title_short Assessing genetic diversity of springtails (Collembola) across the Namib Desert and the potential role of environmental parameters in driving this diversity
title_sort assessing genetic diversity of springtails collembola across the namib desert and the potential role of environmental parameters in driving this diversity
topic DNA barcoding
Redundancy analysis
Namib desert
Collembola
UCTD
url http://hdl.handle.net/2263/67137