Measurement of the time required for a termite to pass through tunnels with different curvatures

Abstract

The subterranean termite, Reticulitermes speratus kyushuensis (Isoptera: Rhinotermitidae), excavate complex tunnel networks below the ground for foraging. The tunnels are either curved or meandering. In our previous study, results showed that termites passed smoothrounded corners faster than they did around sharp corners. Smoothrounded corners can be mathematically quantified by the curvature, representing the amount by which a geometric object deviates from a straight line. The present study explored how the time spent inside a tunnel changes in accordance with the degree of tunnel curvature. To do so, artificial tunnels with different curvatures were constructed in acryl substrates. Tunnels were 5 cm in length with widths of W 2, 3, or 4 mm, and the distance between the two ends of the tunnel was D = 2, 3, 4, or 5 cm. A higher value of D signified a lower curvature. The time () taken by a termite to pass through the tunnel was measured. In the case of W = 2 mm, the values of were statistically equal for D = 2, 3, or 4 cm, while for D = 5 cm was significantly lesser. In the case of W = 3, was statistically more for D = 2 and 3 cm than it was for D = 4 and 5 cm. For W = 4, was statistically equal for D = 2 and 3 cm, while for D = 4 cm was relatively shorter. Interestingly, the value of when D = 5 cm was statistically the same as D = 3 or 4 cm. These resulted from two types of termite behavior: biased walking and zigzag walking. © This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.