A project undertaken at the University of New South Wales, and supervised by A/Prof Terry Ord.
Temperature is a critical factor impacting the behaviour of ectotherms. Meat ants are an iconic Australian ectotherm that construct large, long-lived nests made up of millions of ants.
This project manipulated the conditions experienced by nests over several years, subjecting some to increased cooling and others to increased warming. The work found both conditions induced colonies to shift their nests through budding, otherwise colonies faced extinction. Yet colonies only committed to moving a nest after at least a year of experiencing adverse temperature conditions, relying instead on changing the activity of workers over the short-term. Other experiments documented the remarkable capacity of meat ants to navigate effectively back to the nest after long foraging forays and how these navigation abilities were affected by large changes in ambient (air) temperature.
The meat ant, Iridomyrmex purpureus, are widespread throughout southeastern Australia and construct large nests that often house millions of ants. These nests can be over a decade old and must balance sun exposure and shading to maintain the nest within a particular temperature range. Photo credit: Terry J. Ord UNSW Sydney
This project provided new information on the temperature-dependent activity of a widespread and ecologically important Australian insect. It established a direct casual link between the consequences of temperature stress on the behaviour of individuals, and how this impacts the placement and survival of nests. The project also provided foundational data for assessing the extent to which we can expect ectotherms, like meat ants, to mitigate the impacts of the climate crisis through changes in behaviour.