Gary Bell/ Oceanwide / Grey Nurse Shark (Carcharias taurus), Solitary Islands Marine Park, New South Wales, Australia

Alex Mustard / Tawny nurse sharks (Nebris ferrungineus) at night. Vavuu Atoll, Maldives. Indian Ocean

Shane Gross / Nurse sharks (Ginglymostoma cirratum) two in a courtship dance at sunrise in a mangrove area near Eleuthera, Bahamas.

Alex Mustard / Tawny nurse shark (Nebrius ferrugineus) group, individuals circling each other at dusk. Vavuu Atoll, Maldives. Indian Ocean.

Pete Oxford / Nurse Shark (Ginglymostoma cirratum) Hol Chan Marine Reserve, Belize Barrier Reef, Belize.

Alex Mustard / Nurse shark (Ginglymostoma cirratum) young caught in a fishtrap. North Sound, Grand Cayman, Cayman Islands. Caribbean Sea.

Doug Perrine / Nurse shark {Ginglymostoma cirratum}, Bahamas.

Gerry Ellis / African Elephant (Loxodonta africana) infant begging mother to nurse, Amboseli National Park, Kenya

Gerry Ellis / Nurse log stage five temperate rainforest, Olympic National Park, Washington

Sumio Harada / Red Squirrel (Tamiasciurus hudsonicus) mother returning to her 35 day old babies in nest to nurse them, Rocky Mountains, North America

Doug Perrine / Wild sociable Bottlnose dolphin harasses Nurse shark {Tursiops truncatus} Turks and (Non-ex).

Doug Perrine / Nurse shark on coral reef {Ginglymostoma cirratum} Bahamas, Caribbean Sea (Non-ex).