Termite's Twisted Mandible Presents Fast, Powerful, and Precise Strikes

The asymmetric mandibles of termites are hypothetically more efficient, rapid, and powerful than the symmetric mandibles of snap-jaw ants or termites. We investigated the velocity, force, precision, and defensive performance of the asymmetric mandibular snaps of a termite species, Pericapritermes nitobei. Ultrahigh-speed recordings of termites revealed a new record in biological movement, with a peak linear velocity of 89.7-132.4 m/s within 8.68 μs after snapping, which caused an impact force of 105.8-156.2 mN. High-speed video recordings of ball-strike experiments on termites were analysed using the principle of energy conservation; the left mandibles precisely hit metal balls at the left-to-front side with a maximum linear velocity of 80.3 ± 15.9 m/s (44.0-107.7 m/s) and an impact force of 94.7 ± 18.8 mN (51.9-127.1 mN). In experimental fights between termites and ant predators, Pe. nitobei killed 90-100% of the generalist ants with a single snap and was less likely to harm specialist ponerine ants. Compared with other forms, the asymmetric snapping mandibles of Pe. nitobei required less elastic energy to achieve high velocity. Moreover, the ability of P. nitobei to strike its target at the front side is advantageous for defence in tunnels.