How Scientists “Turn Off” a Shark 🦈🧠

Imagine this is your job: you have to attach a tracker to this tiger shark’s tail, which is pure muscle. What would you do? You probably wouldn’t think to… tickle it.
These scientists did just that. They gently rubbed the shark’s snout because it’s covered with hundreds of pores. These are sensors and help the shark to sense the heartbeat of hidden prey.
So, they are very sensitive, and rubbing them triggers a biological ‘off switch’ called tonic immobility. It’s a temporary paralysis that leaves the shark completely calm for up to 15 minutes.
But that leaves a huge mystery: why would an apex predator have this ‘off switch’?