Present address: Centre for Environmental Stress and Adaptation Research, The University of Melbourne, Parkville, Victoria, Australia 3010.
Phylogeography of sexual Heteronotia binoei (Gekkonidae) in the Australian arid zone: climatic cycling and repetitive hybridization
Article first published online: 21 JUN 2005
Volume 14, Issue 9, pages 2755–2772, August 2005
How to Cite
STRASBURG, J. L. and KEARNEY, M. (2005), Phylogeography of sexual Heteronotia binoei (Gekkonidae) in the Australian arid zone: climatic cycling and repetitive hybridization. Molecular Ecology, 14: 2755–2772. doi: 10.1111/j.1365-294X.2005.02627.x
- Issue published online: 21 JUN 2005
- Article first published online: 21 JUN 2005
- Received 20 January 2005; revision accepted 28 April 2005
- arid zone;
- climatic cycling;
The biota of much of continental Australia have evolved within the context of gradual aridification of the region over several million years, and more recently of climatic cycling between relatively dry and humid conditions. We performed a phylogeographical study of three sexual chromosome races of the Heteronotia binoei complex of geckos found throughout the Australian arid zone. Two of these three races were involved in two separate hybridization events leading to parthenogenetic lineages (also H. binoei), and the third is widespread and broadly sympatric with the parthenogens. Based on our analyses, the three sexual races diversified approximately 6 million years ago in eastern Australia, during a period of aridification, then each moved west through northern, southern, and central dispersal corridors to occupy their current ranges. In each case, the timing of major phylogeographical inferences corresponds to inferred palaeoclimatic changes in continental Australia. This scenario provides a simple explanation for diversification, secondary contact, and hybridization between the races. However, data presented elsewhere indicate that formation of the parthenogens was considerably more recent than the westward expansion of the hybridizing races, and that multiple hybridization events were geographically and temporally distinct. We suggest that cyclical climate changes may have led to regional range changes that facilitated hybridization between the races, which are not currently known to be in sympatry.