Environmental Control of Physiology Lab - Honours projects available in 2010

An Honours project undertaken in this lab would be administered by the Discipline of Physiology.

Animal models are frequently used to understand physiological mechanisms. Comparative Physiologists use the diverse information that can be discovered in a wide variety of non-laboratory animals to help formulate ideas about physiological processes. Current research interests have focused on the environmental control of structure and function in mammals, especially marsupials. Research areas include the photoperiodic control of reproduction, and the seasonal implications for metabolism. Other research relates to the seasonal physiological and endocrinological changes in mammals and their morphological implications. This has involved endocrine influences on non-target physiological systems, such as the renal system. Currently we are developing programmes to look at the interactions between stress, reproduction and ageing, using the small marsupials Antechinus stuartii (brown antechinus) and Sminthopsis macroura (striped-faced dunnart) as animal models.

NOTE: At present the colony of the marsupials, Sminthopsis macroura and Sminthopsis crassicaudata, is based off-campus and is unlikely to be moved to the University of Sydney before early 2008. The projects outlined below are only suitable for students wishing to start mid-2008 at the earliest.

1. The regulation of reproductive physiology by environmental photoperiod

Supervisor + contact details:

• Dr Bronwyn McAllan

The regulation of reproductive physiology by environmental photoperiod is poorly known in marsupials. By manipulating photoperiod and measuring reproductive outcomes in Sminthopsis macroura, including detecting hormonal changes by RIA, we can learn more about the control of seasonal reproduction in marsupials.

2. The regulation of reproduction and metabolism by photoperiod and temperature

Supervisor + contact details:

• Dr Bronwyn McAllan

Seasonal changes in reproduction and torpor use (measured by open flow respirometry) are important for the survival of many small mammals. By exposing the marsupials Sminthopsis macroura and Sminthopsis crassicadata to different photoperiods and temperatures we can understand more about the survival responses of mammals to environmental change.

Selected references:

1. Geiser, F, McAllan, B, Kenagy, G, Hiebert, S. Photoperiod affects daily torpor and tissue fatty acid composition in deer mice. Die Naturwissenschaften. 2007; 94:319-325
2. McAllan, B, Dickman, C, Crowther, M. Photoperiod as a reproductive cue in the marsupial genus Antechinus: ecological and evolutionary consequences. Biological Journal of the Linnean Society. 2006; 87:365-379
3. McAllan, B, Geiser, F. Photoperiod and the timing of reproduction in Antechinus flavipes (Dasyuridae: Marsupialia). Mammalian Biology. 2006; 71:129-138
4. McAllan, B. Dasyurid marsupials as models for the physiology of ageing in humans. Australian Journal of Zoology. 2006; 54:159-172
5. Lippolis, G, Westman, W, McAllan, B, Rogers, L. Lateralisation of escape responses in the stripe-faced dunnart, Sminthopsis macroura (Dasyuridae: Marsupialia). Laterality. 2005; 10:457-70
6. McAllan, B, Westman, W, Joss, J. The seasonal reproductive cycle of a marsupial, Antechinus stuartii: effects of oral administration of melatonin. General and Comparative Endocrinology. 2002; 128:82-90