Biology
The mechanics of jet propulsion and mantle contraction in squid
Quick fact
A squid can accelerate from rest to over 10 body lengths per second in less than a second by contracting its mantle muscles to expel water through a funnel—a feat that relies on the principle of action-reaction (Newton's third law).
Why this is interesting
Imagine being able to shoot through the water by squeezing a balloon—squid do exactly that, and with incredible finesse. But there's a catch: this powerful propulsion comes at a high energy cost. Let's see how it works.