Gary Bell/ Oceanwide / Porcupinefish (Diodon nicthemerus) in defensive posture, Port Phillip Bay, Mornington Peninsula, Victoria, Australia

Juergen Freund / Globefish (Diodon nicthemerus) swimming past a mass of plastic moving in the current, North Sulawesi, Indonesia.

Alex Mustard / Spotted porcupinefish (Diodon hystrix) swimming in open water above a coral reef, West Bay, Grand Cayman, Cayman Islands, British West Indies, Caribbean Sea.

Flip Nicklin / Long-spine Porcupinefish (Diodon holocanthus) in defense posture, North America

Fred Bavendam / Porcupinefish (Diodon nicthemerus) swallows water to puff itself up and points its spines outward as a defense against predators, South Australia

Gary Bell/ Oceanwide / Sea Star (Coscinasterias muricata) feeding on Porcupinefish (Diodon nicthemerus) carcass, Port Phillip Bay, Mornington Peninsula, Victoria, Australia

Gary Bell/ Oceanwide / Porcupinefish (Diodon nicthemerus), Port Phillip Bay, Mornington Peninsula, Victoria, Australia

Franco Banfi / Diamond stingray (Dasyatis brevis) with Longspined porcupinefish (Diodon holocanthus), Cabo Pulmo Marine National Park, Baja California Sur, Mexico

Juergen Freund / Long-spine Porcupinefish (Diodon holocanthus) in its discarded aluminum can home, North Sulawesi, Indonesia. November.

Juergen Freund / Long-spine Porcupinefish (Diodon holocanthus) in its discarded aluminum can home, North Sulawesi, Indonesia. November.

Gary Bell/ Oceanwide / Porcupinefish (Diodon nicthemerus) in defensive posture, Port Phillip Bay, Mornington Peninsula, Victoria, Australia

David Fleetham / Giant porcupinefish (Diodon hystrix) at night. Kauai, Hawaii.