Juergen & Christine Sohns / African Lion (Panthera leo) six week old cubs, Tswalu Game Reserve, South Africa

Juergen & Christine Sohns / African Lion (Panthera leo) six week old cub, Tswalu Game Reserve, South Africa

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub nursing, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cubs playing, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) six-week-old cub nuzzling mother, Jao Reserve, Botswana

Suzi Eszterhas / Leopard (Panthera pardus) mother playing with her six-week-old cub, Jao Reserve, Botswana

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two adults with chicks aged six to eight weeks. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two chicks aged six to eight weeks brooding on parents' feet. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two chicks aged six to eight weeks brooding on parents' feet, one vocalising. Atka Bay, Antarctica. September.

Stefan Christmann / Emperor penguin (Aptenodytes forsteri), two chicks aged six to eight weeks huddling together. Atka Bay, Antarctica. September.

Chien Lee / Asian Brown Tortoise (Manouria emys) male in rainforest, Tawau Hills Park, Sabah, Malaysia