Use the force
Hiding under a rock is a pistol shrimp, and it packs a mighty weapon. The approaching crab is heading into trouble as the shrimp is ready for a fight. At first sight it looks like the shrimp punches the intruder with its claw, but in fact something much stranger is going on. His weapon isn't actually the claw itself, it's an amazing invisible force. The claw snapping shut happens so fast it causes a high velocity water jet which shoots forwards at almost 60 miles an hour - fast enough to vaporise the water and form a bubble. But this is no ordinary bubble. The temperature inside reaches over 4000 degrees and as the bubble collapses this energy is released like a super-heated shockwave, stunning and killing its prey.