Juergen Freund / Split level of large Purple crown jellyfish (Netrostoma setouchina) in shallows of mangroves. Mali Island, Macuata Province, Fiji, South Pacific.

Juergen Freund / Chambered nautilus (Nautilus pompilius) with red whip coral. Osprey Reef, Great Barrier Reef, Queensland, Australia.

Tui De Roy / Dead Sally-lightfoot crab (Grapsus grapsus) washed up in surf, Puerto Egas, James Bay, Santiago Island, Galapagos, Ecuador, May.

Alex Mustard / Oceanic whitetip shark (Carcharhinus longimanus) accompanied by pilotfish (Naucrates ductor) as it cruises beneath the surface of the Red Sea, close to Little Brother Island. The Brothers Islands, Egy...

Pascal Kobeh / Multitudes of Moon jellyfish (Aurelia labiata), Alaska, USA, Gulf of Alaska. Pacific ocean.