Behaviour 2019
Importance of vision in tandem running during colony relocation in an Indian ant Diacamma indicum
Snigdha Mukhopadhyay, Sumana Annagiri. Indian Institute of Science Education and Research (IISER), Kolkata, Mohanpur, West Bengal, India

Visual inputs are essential for navigation in animals to determine the route of their journey and locate their destination. In contrast, several ant species are known to rely on visual inputs for navigation while foraging, little is known about the importance of visual cues when they engage in a goal-oriented task of colony relocation. This study investigated the importance of vision for a tandem-running tropical ant Diacamma indicum during colony relocation by impairing the vision in both eyes of all colony members and comparing our findings with ants having normal vision. On examining 265 tandem runs performed by vision-impaired ants, we found that these ants became tandem leaders, unlike another tandem running ant species, but they had lower efficiency than the controls. They traveled along more tortuous paths at a lower speed, leading to a delay in the overall transportation.  Our results also suggest that these ants use thigmotactic cues from their environment to navigate towards their new nest in the absence of visual inputs. By delineating the role of vision, we are only starting to understand how this multi-modal recruitment behavior tandem running operates.