David Fleetham / Bottletail squid (Sepiadarium kochi) Komodo, Indonesia.

Juergen Freund / Split level of Purple crown jellyfish (Netrostoma setouchina) in shallow waters, Nukubati Island Resort, Macuata Province, Fiji, South Pacific

Juergen Freund / Split level of Purple crown jellyfish (Netrostoma setouchina) in shallow waters, Nukubati Island Resort, Macuata Province, Fiji, South Pacific

Juergen Freund / Purple crown jellyfish (Netrostoma setouchina) in the shallow waters, Nukubati Island Resort, Macuata Province, Fiji, South Pacific

Juergen Freund / Coral bleaching in the northern Great Barrier Reef, Queensland, Australia March 2017.

Juergen Freund / Coral bleaching in the northern Great Barrier Reef, Queensland, Australia March 2017.

Emanuele Biggi / Land crab (Geosesarma sp.) which raids Pitcher plant (Nepenthes ampullaria) for prey, Sarawak, Borneo.

Alex Mustard / Whitebelly damselfish (Amblyglyphidodon leucogaster) pair spawning / laying eggs on a seafan (Annella mollis). Ras Mohammed National Park, Sinai, Egypt. Red Sea.

Alex Mustard / Bullethead parrotfish (Chlorurus sordidus) male, close up of eye, whilst sleeping at night. The Alternatives, Sinai, Egypt. Red Sea

Alex Mustard / Whitebelly damselfish (Amblyglyphidodon leucogaster) male and female laying egg on old gorgonian branch. The Alternatives, Sinai, Egypt. Red Sea.

Alex Mustard / Bluestreak cleaner wrasse (Labroides dimidiatus) sticking its head into the mouth of a Red Sea fusilier (Caesio lunaris) during a cleaning session. Small Crack, Sha'ab Mahmud, Sinai, Egypt. Red Se...

Alex Mustard / Orange-finned anemonefish (Amphiprion chrysopterus) guarding their recently spawned red eggs on a rock next to the host anemone. Rock Islands, Palau, Micronesia. Tropical west Pacific Ocean.