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Australian Journal of Zoology Australian Journal of Zoology Society
Evolutionary, molecular and comparative zoology
RESEARCH ARTICLE

Characterisation and cross-amplification of sex-specific genetic markers in Australasian Egerniinae lizards and their implications for understanding the evolution of sex determination and social complexity

Alix Bouffet-Halle A , Weizhao Yang B , Michael G. Gardner C D , Martin J. Whiting E , Erik Wapstra https://orcid.org/0000-0002-2050-8026 A , Tobias Uller B and Geoffrey M. While https://orcid.org/0000-0001-8122-9322 A *
+ Author Affiliations
- Author Affiliations

A School of Natural Sciences, University of Tasmania, Hobart, Tas. 7005, Australia.

B Department of Biology, Lund University, Lund, Sweden.

C College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia.

D Evolutionary Biology Unit, South Australian Museum, Adelaide, SA 5001, Australia.

E Department of Biological Sciences, Macquarie University, Sydney, NSW 2109, Australia.

* Correspondence to: gwhile@utas.edu.au

Handling Editor: Steven Cooper

Australian Journal of Zoology 69(2) 33-40 https://doi.org/10.1071/ZO21023
Submitted: 11 June 2021  Accepted: 29 November 2021   Published: 3 February 2022

© 2021 The Author(s) (or their employer(s)). Published by CSIRO Publishing

Abstract

Sex is a pervasive factor that underpins functional phenotypic variation across a range of traits. Although sex can usually be distinguished morphologically, in some species this is not possible. The development of genetic markers for sex identification is, thus, key if we are to incorporate sex into an understanding of ecological or evolutionary process. Here we develop genetic markers for the identification of sex within an iconic Australian lizard group, the Egernia group, which is notable for its complex social behaviour. We used restriction-site associated DNA sequencing to characterise sex-specific genetic sequences for a key member of the group, Liopholis whitii, and designed primers for four of these putative sex-specific sequences. These primers amplified across some, but not all, species of the group. Our results provided several important insights. They suggest conservatism of a XX/XY sex determination system within the group as well as sex-specific genomic regions that appear independent of the conserved genomic regions identified in other skink species. More broadly, the development of sex markers for the Egernia group opens up a range of potential research questions related to the role that sex plays in the mediation of social behaviour and, through this, the emergence and stability of social life.

Keywords: Egernia, Liopholis, RAD-Seq, reptiles, sex chromosomes, sex determination, sex marker, social behaviour.


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