Pufferfish have a couple of ways to defend themselves: They have an incredibly potent toxin in their flesh, and they can puff themselves out into a spine-covered ball that’s pretty difficult to eat.

Pufferfish can balloon into a spikey sphere within moments of sensing a nearby threat, and while it may seem like these creatures hold their breath as they inflate, they can actually breathe as they ...

Breakthroughs, discoveries, and DIY tips sent every weekday. Terms of Service and Privacy Policy. How does the pufferfish stay inflated? Not by holding its breath, a ...