student profile: Miss Georgia Thomas


Thesis work

Thesis title: Characterisation of factors influencing male reproductive success in the eastern grey kangaroo (Macropus giganteus).

Supervisors: Catherine GRUEBER , Mark ELDRIDGE, Catherine HERBERT , Gabriel MACHOVSKY-CAPUSKA

Thesis abstract:

The process of natural selection drives the sustained survival of the fittest individuals within populations. Both natural and sexual selection pressures select for certain genetic, physiological, anatomical and/or behavioural traits that enhance individual reproductive success. Through the study of these traits and their relationship with reproductive success, valuable information regarding specific species attributes and long term evolutionary relationships can be extrapolated. A large proportion of these studies have focused on eutherian mammals, birds and reptile species leaving a large knowledge gap in the validation of evolutionary systems of the marsupial mammal lineage. The Eastern grey kangaroo (Macropus giganteus) is one of the largest existing marsupial species, endemic to the eastern and southern states of Australia. This species exhibits a polygamous mating system, established social structuring, prominent sexual size dimorphism and is abundant in accessible wild populations. Through discerning evolutionary tactics in this abundant and accessible species, research on closely related, elusive endangered marsupial populations, such as the bridled nailtail wallaby (Onychogalea fraenata), can be guided or inferred. The present study aims to identify factors influencing male reproductive success in the Eastern grey kangaroo. This will involve analysing various male kangaroo attributes, including body size, reproductive behaviours, genetics and health parameters. These factors will then be compared to the number of offspring sired by each male (reproductive success). We will then determine which factors are significant in influencing male reproductive success.

Selected grants


  • Characterisation of factors influencing male reproductive success in the eastern grey kangaroo (Macropus giganteus); Herbert C, Thomas G; Equity Trustees Limited/Holsworth Wildlife Research Endowment.

Note: This profile is for a student at the University of Sydney. Views presented here are not necessarily those of the University.