Data for: Pendulum-based measurements reveal impact dynamics at the scale of a trap-jaw ant

Small organisms can produce powerful, sub-millisecond impacts by moving
tiny structures at high accelerations. We developed and validated a
pendulum device to measure the impact energetics of microgram-sized
trap-jaw ant mandibles accelerated against targets at 105 m s-2. Trap-jaw
ants (Odontomachus brunneus; 19 individuals; 212 strikes) were suspended
on one pendulum and struck swappable targets that were either attached to
an opposing pendulum or fixed in place. Mean post-impact kinetic energy
(energy from strike converted to pendulum motion) was higher with a stiff
target (21.0-21.5 µJ) than a compliant target (6.4-6.5 µJ). Target
mobility had relatively little influence. Mean contact duration of strikes
against stiff targets was shorter (3.9-4.5 ms) than against compliant
targets (6.2-7.9 ms). Shorter contact duration was correlated with higher
post-impact kinetic energy. These findings contextualize and provide an
energetic explanation for the diverse, natural uses of trap-jaw ant
strikes such as impaling prey, launching away threats, and performing
mandible-powered jumps. The strong effect of target material on energetic
exchange suggests material interactions as an avenue for tuning
performance of small, high acceleration impacts. Our device offers a
foundation for novel research into the ecomechanics and evolution of tiny
biological impacts and their application in synthetic systems.