A three-week-old chihuahua puppy named Tom Thumb poses in a tea cup on April 7, 2009 in Renton, Scotland. The pup, which measures eight inches long, is thought to be one of the smallest dogs born in the UK and is just two inches short of a world record. (Photo by Jeff J Mitchell/Getty Images)

Revellers chase a bull into the sea during the “Bous a la Mar” festival on July 14, 2011 in Denia, Spain. The Spanish “Bous a la Mar” or “Bulls to the Sea” festival is held in honour of the Santisima Sangre and commemorate a monk named Pedro Esteve, who, as the legend has it, saved the coastal town of Denia from a plague in 1633. The bulls chased into the sea are later brought back to land by small boats. (Photo by Jasper Juinen/Getty Images)

An adorable 11-week old lion cub named Karis had a very exciting day playing in a pile of autumn leaves that her keeper swept into her enclosure at the Blair Drummond Safari and Adventure Park in Scotland. This proved to be a very wise decision on her keeper’s part, as she seems to have had the time of her life frolicking around in the pile of leaves

California-based photographer Seth Casteel made his name taking photographs of dogs underwater, but before that, he was snapping cats on land.

Paddington the Shar Pei dog and his best friend cat named Butler are perhaps the cutest pair you've ever seen. The two of them live with their owner Annie Jacob and three other cats in Tasmania on the south coast of Australia and are pretty much inseparable.

A baby hippo swims under the water in its enclosure at Prague Zoo, Czech Republic, February 24, 2016. The baby was born on January 28, and is yet to be named. (Photo by David W. Cerny/Reuters)