A heat-stressed koala waits as a resident pours water on its back on December 19, 2015 in Adelaide, Australia. Adelaide is experiencing an extreme heatwave, with temperatures reaching over 40 degrees for five consecutive days. (Photo by Morne de Klerk/Getty Images)
California-based photographer Seth Casteel made his name taking photographs of dogs underwater, but before that, he was snapping cats on land. In fact, they were his first animal subjects. Casteel’s new book, Pounce – a follow-up to his bestselling Underwater Dogs and Underwater Puppies – features more than 80 photographs of playful cats doing what they do best. Here: Fuzzbucket. (Photo by Seth Casteel/Hachette Australia)
Iberian lynx Mistral jumps in a field after being released by Portugal's Minister of Environment Joao Matos Fernandes (unseen) and others in the Mount Milhouro (Herdade da Cela) region in Mertola, Portugal, 13 May 2016. Mistralis the 18th lynx bred in captivity released since late 2014. (Photo by Nuno Veiga/EPA)
Marine biologist Simon Pierce, who studies whale sharks, happened to be in the right place at the right time to capture amazing photo off Cancun, Mexico. (Photo by Simon Pierce/Mercury Press/Caters News)
A group of children and their dog playing an Easter game in Cardiff. The game involves trying to eat an Easter egg off a piece of string without using their hands. (Photo by Richards/Fox Photos/Getty Images). 26th March 1937