News Item

How Ants Use Vision When Homing Backward

How Ants Use Vision When Homing Backward

The following title is included in this week's posted papers focussing on navigation and orientation.

Summaries of all papers have been circulated to members of the Animal Navigation Forum and full papers are available in the ANG Resources directory at the link below (available to non-members).

Schwarz, S., Mangan, M., Zeil, J., Webb, B. & Wystrach, A. 2017 How Ants Use Vision When Homing Backward. Current Biology. doi: 10.1016/j.cub.2016.12.019. Schwarz6 2017 (featured in Nature Research Highlights: http://dx.doi.org/10.1038/541439b)

Ants can navigate over long distances between their nest and food sites using visual cues [1, 2]. Recent studies show that this capacity is undiminished when walking backward while dragging a heavy food item [3–5]. This challenges the idea that ants use egocentric visual memories of the scene for guidance [1, 2, 6]. Can ants use their visual memories of the terrestrial cues when going backward? Our results suggest that ants do not adjust their direction of travel based on the perceived scene while going backward. Instead, they maintain a straight direction using their celestial compass. This direction can be dictated by their path integrator [5] but can also be set using terrestrial visual cues after a forward peek. If the food item is too heavy to enable body rotations, ants moving backward drop their food on occasion, rotate and walk a few steps forward, return to the food, and drag it backward in a now-corrected direction defined by terrestrial cues. Furthermore, we show that ants can maintain their direction of travel independently of their body orientation. It thus appears that egocentric retinal alignment is required for visual scene recognition, but ants can translate this acquired directional information into a holonomic frame of reference, which enables them to decouple their travel direction from their body orientation and hence navigate backward. This reveals substantial flexibility and communication between different types of navigational information: from terrestrial to celestial cues and from egocentric to holonomic directional memories.



  • 01 February 2017
  • Animal Navigation Group

Contact Us

The Royal Institute of Navigation
1 Kensington Gore
London
SW7 2AT

+44 (0)20 7591 3134
admin@rin.org.uk

E-Mail Communication

The Royal Institute of Navigation periodically sends out email updates to its membership and those who have subscribed to events and conferences run by the RIN. In doing so, the RIN takes all reasonable precautions to ensure that the emails are only sent to those who have requested them, and that no third party can make unauthorised use of any @rin.org.uk email address to send out mailings.If you receive unsolicited mail from any @rin.org.uk address then please inform us at admin@rin.org.uk and we will take appropriate action.

Join the RIN

You can apply for any category of RIN membership by completing the online membership application form and paying using our secure credit/debit card payment system.

Join Now