Steven David Miller / Sand bubble patterns created by Sand bubbler crabs (Scopimera inflata), Cape Hillsborough National Park, Queensland, Australia. September.

Juergen Freund / Wide-angle timelapse of Sand bubbler crabs (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Herita...

Juergen Freund / Sand bubbler crabs (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Heritage Area, Cape Tribulatio...

Juergen Freund / Sand bubbler crab (Dotillidae) feeding, filtering detritus and plankton from sand and discarding the processed sand as pellets, which cover the beach, Wet Tropics World Heritage Area, Cape Tribulation...

Remi Masson / European crayfish (Astacus astacus) in a lake. Alps, Switzerland, July.

David Fleetham / Cleaner wrasse (Labroides dimidiatus) swimming alongside Golden damsel (Amblyglyphidodon aureus) looking for parasites, Fiji, Pacific Ocean.

Solvin Zankl / Bioluminescent Sea-fireflies (Vargula hilgendorfii) producing a bright blue light. The light is produced by mixing two chemicals together in the presence of oxygen and is for mating displays or defenc...

Nick Upton / Common prawns (Palaemon serratus) and a Rock goby (Gobius paganellus) feeding on a dead Montagu's crab (Xantho hydrophilus) in a rockpool, Cornwall, England, UK, September.

Nick Upton / Rock goby (Gobius paganellus) stealing food from a scavenging Common prawn (Palaemon serratus) in a rockpool, Cornwall, England, UK, September.

Sue Daly / Common lobster (Homarus gammarus) shovelling gravel out of a hole, Sark, British Channel Islands, UK, August.

Sue Daly / Long legged spider crab (Macropodia) walking across the seabed, Sark, British Channel Islands, UK, June.

Ammonite / Close up of a Common snail (Cornu aspersum) moving, with Woodlice (Oniscidea). Controlled conditions.