- Zoe Brain
It's interesting that no Koalas have been reported as having been attacked by T. plummetus.
Is it possible that the Koala's exclusive diet of eucalyptus leaves may taint the meat, making them ineligible as prey? If so, the diet and digestive system may be an evolutionary adaptation.
The lack of evidence for these "folk remedies" may be due to the ethical problems in conducting double-blind experiments using human subjects. If two sets of tourists (for example) are selected, one set told to anoint their necks with vegemite, the other not - and the remedy is effective - then we have endangered the control group.
Perhaps a study could be conducted on all tourists journeying into the bush. Get them to all put vegemite on their necks, and if none get attacked over a 5-year period, we would have evidence suggesting the possibility of effectiveness - while still being able to pass ethical review.