Murdoch University Research Repository

Welcome to the Murdoch University Research Repository

The Murdoch University Research Repository is an open access digital collection of research
created by Murdoch University staff, researchers and postgraduate students.

Learn more

Population genetic structure of island and mainland populations of the quokka, Setonix brachyurus (Macropodidae): a comparison of AFLP and microsatellite markers

Alacs, E.A., Spencer, P.B.S.ORCID: 0000-0002-4938-2615, Tores, P.J. and Krauss, S.L. (2011) Population genetic structure of island and mainland populations of the quokka, Setonix brachyurus (Macropodidae): a comparison of AFLP and microsatellite markers. Conservation Genetics, 12 (1). pp. 297-309.

Link to Published Version:
*Subscription may be required


Translocation and reintroduction are important tools for the conservation or recovery of species threatened with extinction in the wild. However, an understanding of the potential genetic consequences of mixing populations requires an understanding of the genetic variation within, and similarities among, donor and recipient populations. Genetic diversity was measured using two independent marker systems (microsatellites and AFLPs) for one island and four small remnant mainland populations of Setonix brachyurus, a threatened medium sized macropod restricted to fragmented habitat remnants and two off-shore islands in southwest Australia. Microsatellite diversity in the island population (Rs = 3.2, He = 71%) was similar to, or greater than, all mainland populations (Rs = 2.1-3.9, He = 34-71%). In contrast, AFLP diversity was significantly lower in the island population (PPL = 20. 5; Hj = 0.118) compared to all mainland populations (mean PPL = 79.5-89.7; mean Hj = 0.23-0.29). Microsatellites differentiated all (mainland and island) populations from each other. However, AFLP only differentiated the island population from the mainland populations-all mainland populations were not significantly differentiated from each other for this marker. Given a known time since isolation of the island population from the mainland (6,000 years ago), and an overall more conservative rate of evolution of AFLP markers, our results are consistent with mainland populations fragmenting thousands of years ago (but 6,000 years), probably as a consequence of reduced rainfall and the constriction of the preferred mesic habitat of quokkas. Our results also support a recent history of severe population bottlenecks in mainland populations, and a long history of bottlenecks of the island population, but reflect a recent explosion in numbers since European occupation of the island. Our results indicate that translocation of island populations to supplement mainland populations would introduce genetically markedly differentiated, and possibly maladapted, individuals.

Item Type: Journal Article
Murdoch Affiliation(s): School of Biological Sciences and Biotechnology
Publisher: Kluwer Academic Publishers
Copyright: © 2010 Springer Science+Business Media B.V.
Item Control Page Item Control Page