Juergen Freund / Whale shark and person swimming in silhouette {Rhinicodon typus} Indo Pacific

Norbert Wu / Blue Swimming Crab (Portunus pelagicus) pair mating, South Australia, Australia

Juergen Freund / A factory of women taking the meat out of cooked Blue swimmer crabs (Portunus pelagicus) to pack for export to America. Northern Palawan, Phillipines, May 2009

Juergen Freund / Blue swimmer crab (Portunus pelagicus) on the sea bed. Lembeh Strait, North Sulawesi, Indonesia

Juergen Freund / Swimmer crab / Harlequin crab (Lissocarcinus laevis) and Tube anemone. Lembeh Strait, North Sulawesi, Indonesia.

Toby Roxburgh / Aerial view of swimmer off Pipitos beach, northern Corfu, Greece, June 2010.

Robert Valentic / Broad banded sand swimmer skink {Eremiascincus richardsonii} foraging at dusk, Westmar, Queensland, Australia

Robert Valentic / Ghost Skink (Eremiascincus phantasmus) Lake Blanche, South Australia

Chris Newbert / Swimmer Crab (Lissocarcinus sp) in Anemone, 40 feet deep, Papua New Guinea

Chris Newbert / Harlequin Crab (Lissocarcinus orbicularis) on Tube Anemone, the crab lives protected on the tube of the anemone as its stinging tentacles wave in front of it, 40 feet deep, Papua New Guinea

Doug Perrine / Swimmer strokes Melon headed whale calf {Peponocephala electra} Hawaii, USA.

Todd Pusser / Atlantic spotted dolphin and swimmer underwater {Stenella frontalis} Bahamas, Atlantic

Chris Newbert / Rainbow Swimming Crab (Charybdis erythrodactyla) 20 feet deep, Hawaii

Chris Newbert / Rainbow Swimming Crab (Charybdis erythrodactyla) 20 feet deep, Hawaii

Birgitte Wilms / Swimmer Crab (Lissocarcinus sp) on Leopard Sea Cucumber (Bohadschia argus) 50 feet deep, Solomon Islands

Norbert Wu / Sea Wasp (Chironex fleckeri) warning sign notifying swimmers that sting can be fatal, Queensland, Australia

Norbert Wu / Swimmer and coral sand beaches with unique granite formations, Seychelles

Fred Bavendam / Southern Keeled Octopus (Octopus berrima) with a Sand Crab (Ovalipes sp) it has captured to eat, Edithburgh, South Australia

Fred Bavendam / Blue Swimming Crab (Portunus pelagicus) with its claws spread wide in a defensive posture, Edithburgh, South Australia, Australia

Flip Nicklin / Swimmer delivering mail to research boat, Sri Lanka

Norbert Wu / Swimmer Richard Drewelow, Stanford, California

Norbert Wu / Swimmer Richard Drewelow, Stanford, California