CTMax and VTMax of leaf-cutting ants

My undergraduate research project was on physiological and behavioral responses to heat stress in leaf-cutting ants (Atta sexdens rubropilosa). In this project, I was interested in understanding how intrinsic and extrinsic factors (e.g., body size, humidity, experimental design) affected Critical and Voluntary thermal limits of  ants. 

In this work we found that while size does not predict critical limits, medium-size workers can take more heat before voluntarily leave a stressful environment relative to their smaller or larger sisters. This is cool because medium-size workers are responsible for leaving the colony in search of food (ie foraging), whereas their sisters take upon other tasks within the colony. 

The punchline here is that since critical thermal limits was not different among animals of different sizes, the medium-size foragers do not hold a physiological advantage to tolerate more heat, but rather appear to choose to stay under stressful conditions relative to other ants, which is really cool if you ask me!! 

The full report is open access and can be found here.