Dissertation
Investigating a Dinosaur: Conservation genetics and demographic analysis of the endangered cycad species Cycas megacarpa and implications for the proposed translocation
University of the Sunshine Coast, Queensland
Doctor of Philosophy, University of the Sunshine Coast
2016
DOI:
https://doi.org/10.25907/00546
Abstract
Cycads are well known iconic plant species known to have existed over 200 million years ago before dinosaurs roamed the earth. The species Cycas megacarpa is one of approximately 300 cycad species descended from lineages of that era now spread across the tropics and subtropics in Africa, Central America, and regions of Asia and in Australia. Approximately 82% of cycad species are considered to be threatened. Cycads in general are under threat from many different sources. These threats range from the broad problems associated with climate change to more direct effects like habitat transformation. The limited seed dispersal range of cycads, the characteristic longevity of individuals coupled with the dioecious nature suggests that the impact of habitat fragmentation on individual populations and species as a whole are not straightforward and require specific study. Cycas megacarpa is listed as an endangered cycad currently under threat from urban, rural and commercial infrastructure development. Cycad populations are often disjunct and scattered throughout the landscape and it has been thought that gene flow between populations is minimal or non-existent. Recent genetic studies on cycad species have found mixed results with some species showing little genetic differentiation and some showing lower levels of gene flow in contiguous habitat over those in fragmented habitat. This study investigates the effect fragmentation has had on the genetic structure of C. megacarpa populations across its entire range as well as the implications of translocating large numbers of cycads from several populations due to the construction of a gas transmission pipeline. This study focused on three different scales of analysis; a landscape scale involving the whole species, a regional scale involving multiple populations in the same geographic region, and a within population scale focusing on four individual populations.
Details
- Title
- Investigating a Dinosaur: Conservation genetics and demographic analysis of the endangered cycad species Cycas megacarpa and implications for the proposed translocation
- Authors
- Heather E James
- Contributors
- Alison Shapcott (Supervisor)
- Awarding institution
- University of the Sunshine Coast
- Degree awarded
- Doctor of Philosophy
- Publisher
- University of the Sunshine Coast, Queensland
- DOI
- 10.25907/00546
- Organisation Unit
- School of Science and Engineering - Legacy; University of the Sunshine Coast, Queensland; Academic Support Unit; School of Science, Technology and Engineering; Centre for Bioinnovation
- Language
- English
- Record Identifier
- 99450911802621
- Output Type
- Dissertation
- Research Statement
- false
Metrics
115 File views/ downloads
904 Record Views