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RESEARCH ARTICLE
Contents Vol 20(2)

Generation of sex ratio biases in the red-tailed phascogale (Phascogale calura)

W. K. Foster A B D and D. A. Taggart A B C
+ Author Affiliations
- Author Affiliations

A School of Earth and Environmental Sciences, University of Adelaide, Adelaide, SA 5005, Australia.

B Zoos South Australia, Frome Road, Adelaide, SA 5000, Australia.

C School of Medical Sciences, University of Adelaide, Adelaide, SA 5005, Australia.

D Corresponding author. Email: wendy.foster@adelaide.edu.au

Reproduction, Fertility and Development 20(2) 275-280 https://doi.org/10.1071/RD07031
Submitted: 15 February 2007  Accepted: 12 November 2007   Published: 4 January 2008

Abstract

Male semelparous dasyurid species are annual breeders that use a promiscuous mating system. These species have shown biases in litter sex ratios and, with females producing more young than they have available teats, this provides an opportunity for the manipulation of the sex ratio at birth. The sex ratio of embryos and pouch young, and the degree of embryonic overproduction, in red-tailed phascogales (Phascogale calura) was investigated to gain an understanding of the mechanism by which sex biases may be generated. The sex ratio of embryos did not differ from parity, but a male bias was observed in young attaching to teats. Females produced an average of 15.1 ± 1.9 corpora lutea and 10.5 ± 3.5 viable embryos, with no difference in fecundity observed with female age or weight. Because females only have eight teats, the overproduction of young, and male-biased attachment, was sufficient to explain the observed male bias in pouch young. No relationship was observed between maternal weight and sex ratio, but heavier females did tend to produce more ova. Meta-analysis of studies providing information on litter sex ratios in male semelparous dasyurid species did not show any consistent trend.

Additional keywords: dasyurid, fecundity, marsupial, reproductive investment.


Acknowledgements

The authors thank Adelaide Zoo for their assistance with animal housing, maintenance and project funding and Alice Springs Desert Park for supplying the animals. The authors also thank Natasha Sankovic and Monica Ruibal for providing primer sequences for the sexing of young and Lisa Miller and Tom Sullivan from the Public Health Department, University of Adelaide, for their assistance with the meta-analysis. Funding was obtained from the Royal Zoological Society of South Australia, the Schultz Foundation and a post-graduate scholarship from the University of Adelaide.


References

Banks, S. C. , Ward, S. J. , Lindenmayer, D. B. , Finlayson, G. R. , Lawson, S. J. , and Taylor, A. C. (2005). The effects of habitat fragmentation on the social kin structure and mating system of the agile antechinus, Antechinus agilis. Mol. Ecol. 14, 1789–1801.
| Crossref | GoogleScholarGoogle Scholar | PubMed | Hughes R. L. (1982). Reproduction in the Tasmanian devil Sarcophilus harrisii (Dasyuridae, Marsupialia). In ‘Carnivorous Marsupials’. (Ed. M. Archer.) pp. 49–63. (Royal Zoological Society of New South Wales: Sydney.)

Kraaijeveld-Smit, F. J. L. , Ward, S. J. , and Temple-Smith, P. D. (2002). Multiple paternity in a field population of a small carnivorous marsupial, the agile antechinus, Antechinus agilis. Behav. Ecol. Sociobiol. 52, 84–91.
| Crossref | GoogleScholarGoogle Scholar | Lee A. K., Woolley P., and Braithwaite W. (1982) Life history strategies of dasyurid marsupials. In ‘Carnivorous Marsupials’. (Ed. M. Archer.) pp. 1–11. (Royal Zoological Society of New South Wales: Sydney.)

Low, B. S. (1978). Environmental uncertainity and the parental strategies of marsupials and placentals. Am. Nat. 112, 197–213.
| Crossref | GoogleScholarGoogle Scholar | Selwood L. (1982). Brown antechinus Antechinus stuartii: management of breeding colonies to obtain embryonic material and pouch young. In ‘The Management of Australian Mammals in Captivity’. (Ed. D. Evans.) pp. 31–37. (Zoological Board of Victoria: North Melbourne.)

Selwood, L. (1983). Factors influencing pre-natal fertility in the brown marsupial mouse, Antechinus stuartii. J. Reprod. Fertil. 68, 317–324.
| PubMed | Taggart D. A., Shimmin G. A., Dickman C. R., and Breed W. G. (2003) Reproductive biology of carnivorous marsupials: clues to the likelihood of sperm competition. In ‘Predators with Pouches’. (Eds M. E. Jones, C. R. Dickman and M. Archer.) pp. 358–375. (CSIRO Publishing: Collingwood.)

Trivers, R. L. , and Willard, D. E. (1973). Natural selection of parental ability to vary the sex ratio of offspring. Science 179, 90–92.
| Crossref | GoogleScholarGoogle Scholar | PubMed | Tyndale-Biscoe C. H., and Renfree M. (1987). ‘Reproductive Physiology of Marsupials.’ (Cambridge University Press: Melbourne.)

Walsh, P. S. , Metzger, D. A. , and Higuchi, R. (1991). Chelex® 100 as a medium for simple extraction of DNA for PCR-based typing from forensic material. Biotechniques 10, 506–513.
| PubMed | Ward S. J. (2003) Biased sex ratios in litters of carnivorous marsupials: why, when and how? In ‘Predators with Pouches’. (Eds M. E. Jones, C. R. Dickman and M. Archer.) pp. 376–382. (CSIRO Publishing: Collingwood.)

Woolley, P. (1991). Reproduction in Dasykaluta rosamondae (Marsupialia: Dasyuridae): field and laboratory observations. Aust. J. Zool. 39, 549–568.
| Crossref | GoogleScholarGoogle Scholar |

Wright, D. D. , Ryser, J. T. , and Kiltie, R. A. (1995). First-cohort advantage hypothesis: a new twist on facultative sex ratio adjustment. Am. Nat. 145, 133–145.
| Crossref | GoogleScholarGoogle Scholar |