A globular springtail jumping from the ground takes 1.5 milliseconds to become airborne and accelerates upward at 798 metres/second², or 81 gravities. Interestingly, although they are six-legged arthropods, springtails are not considered insects because they have internal mouth parts, as opposed to the external mouth parts of Insecta.
Video from “Ant Lab”. Interesting. Any connection with Fourmilab?
Just the name.
Motion of the head during acceleration is notable. It fully flexes ventrally. I can’t help but wonder if the head would remain attached to the thorax were a human body subjected to this many G’s with the force applied from low in the body, as it is here.
The human body is surprisingly robust in surviving transient accelerations from impacts, as the work of John Stapp demonstrated in rocket sled experiments in the 1950s, surviving deceleration of 46.2 g over 1.37 seconds. But that’s about the limit. The U.S. National Highway Traffic Safety Administration says the 50% lethal impact acceleration for an adult male is 75 g, adult female 65 g, and 50 g for a child, with the impact assumed to be on the chest/stomach. The acceleration to snap an unbraced neck would probably be much less.