Directional selection by the subterranean termite Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) at tunnel intersections
Article first published online: 15 OCT 2010
© 2010 The Entomological Society of Japan
Volume 13, Issue 4, pages 363–366, December 2010
How to Cite
KU, S. J., SU, N.-Y. and LEE, S.-H. (2010), Directional selection by the subterranean termite Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae) at tunnel intersections. Entomological Science, 13: 363–366. doi: 10.1111/j.1479-8298.2010.00402.x
- Issue published online: 28 DEC 2010
- Article first published online: 15 OCT 2010
- Received 9 January 2010; accepted 5 May 2010.
- directional preference;
- foraging efficiency;
- termite tunnel network;
- tunnel intersection
Subterranean termites construct complicated tunnel networks for foraging below ground. Thus, they often encounter tunnel intersections during foraging activity. Directional selection by termites at intersections is likely to affect foraging efficiency because depending on their selection, the path length from food resources to the nest can vary significantly. In order to understand how termites are guided to choose the most economical path without the use of pheromones, we artificially excavated two tunnels of varying widths (W1 and W2; 2, 3, or 4 mm) that intersected at a 90° angle in each of nine soil-filled arenas. We observed the directional selection of termites at intersections in arenas with combinations of W1 (mm) and W2 (mm) (W1, W2). For (W1, W2) = (2, 2) and (4, 4), termites statistically equally chose the three directions left, right, and straight, while for the (3, 3) arena combination, termites preferentially decided to go straight. On the other hand, for (W1, W2) = (2, 3) (2, 4), and (3, 4), termites advancing from narrower tunnels into intersections tended to turn right or left, while termites coming from the wider tunnel were more inclined to go straight. On the assumption that a wider tunnel is more frequently used by termites in the field, we can deduce that the wider tunnel may represent the most efficient/shortest path. Thus, this simple selection mechanism can prevent termites from deviating from the most economical path.