2019 Completion Abstracts
Laura Fernandez Winzer
Talk Title: Impacts of the invasive pathogen myrtle rust on Australian native communities.
Abstract: Despite ongoing research into the invasion of the fungal pathogen myrtle rust (Austropuccinia psidii) in Australia, few studies have attempted to examine the impacts it has on natural native communities at both the species- and community-level. This is surprising considering that it infects the Myrtaceae, one of the dominant plant families in Australia. Furthermore, the lack of a national program collating data on A. psidii spread, hosts and impacts makes restoration and conservation decision making challenging for natural resource managers. Therefore, the overarching aim of Laura’s PhD thesis was to determine the impacts of the invasive pathogen myrtle rust on Australian native vegetation communities.
Talk Title: Lizard learning: The relationship between social/ mating system and behavioural flexibility
Abstract: Comparative cognition recently advanced towards a wider taxonomic approach evidenced by an increase in non-avian reptile learning studies but our knowledge still exhibits many gaps. In primates, social complexity was linked to enhanced cognitive abilities and my aim was to investigate if sociality affects cognition such as behavioural flexibility, the ability to cope with changes, in four Australian lizard species using the ID/ED attentional set-shifting task. To test behavioural flexibility, I used several colour/ shape discriminations including reversals, an acquisition of a new colour/ shape and a shift from colour to shape (and vice versa). Moreover, I tested how age affects learning and if behavioural flexibility correlates with unpredictable environmental conditions. All four tested species discriminated between one-dimensional stimuli, however, only three out of four showed behavioural flexibility and only two species successfully completed the shift stage likely learning each set of stages like a new problem. Furthermore, juvenile lizards learnt at adult levels and behavioural flexibility was enhanced in the arid-adapted species experiencing high unpredictability in resource availability. Neither trials to criterion nor the probability of making a correct choice differed between the tested species in any stage implicating no adaptations based on sociality in the tested context. Furthermore, the fourth tested, non-Egernia species, failed to perform even a single reversal likely because of a strong side bias. Overall, my results contribute important new insights into lizard cognition, however, we need more data on a broader range of lizards to make distinct conclusions on how sociality or ecology affect learning.
Talk Title: The biology and ecology of Genoplesium baueri R.Br., an endangered terrestrial orchid endemic to New South Wales, Australia
Abstract: The aim of this research was to examine the demographics and biology of Genoplesium baueri R.Br., an endangered terrestrial orchid species endemic to the Sydney Basin, New South Wales. This was done by carrying out a systematic study (2009-18) of all individual plants in two key northern G. baueri populations. The number and variation in population and plant size; reproductive effort; timing of population emergence and field mortality were studied. These results and natural history observations were used to construct a diagram of the above- and below-ground stages of the proposed lifecycle of plant development and mortality of G. baueri.