“Hippo Chase”. As we approached the camp the Selinda Reserve of northern Botswana our boat passed by a hippo resting in the water. I turned around to look back at the boat's wake and saw the hippo charging after us! The hippo must've been tired from an all-nighter because he was angry. He rose way up out of the water three times trying to chase our boat! He was coming at us with such force that he created a wake of his own. Photo location: Selinda Reserve of northern Botswana. (Photo and caption by Curtis Simmons/National Geographic Photo Contest)

New species have been created by an enterprising artist who has merged photos of animals together in this incredible series of pictures. Californian Sarah DeRemer, 25, started making hybrid animals as a way to improve her photoshop skills. Here: cross between a tabby cat and a sparrow. (Photo by Sarah DeRemer/Caters News)

In this Sunday, March 2, 2014 photo, animal barber Mohamed Mahmoud shaves a customer's initials onto the rump of a donkey in Cairo, Egypt. Clients typically request for regular trims to keep animals cool in the summer, initials in English letters, and patterns – but sometimes they give Mahmoud full creative license. (Photo by Maya Alleruzzo/AP Photo)

Indian authorities hold a tiger skin as they set fire to a stockpile of illegal wildlife parts at the Delhi Zoo in New Delhi, India, Sunday, November 2, 2014. A stockpile of tiger skins, elephant tusks, rhino horns and other illegal animal parts were burned Sunday in an effort to discourage wildlife smuggling in South Asia. (Photo by Tsering Topgyal/AP Photo)

There is nothing more endearing than seeing true friendship and love. Especially, if it as improbable as that of a big dog and a tiny kitten. Somehow, animals feel when they are dealing with a baby. For example, no matter how much a toddler will tug on the tail of a cat and play roughly with it, it will never or very rarely fight back. This set of pictures taken by Jessie Pon shows a tiny kitten mistaking an adult golden retriever for his mother. Though it may hurt the dog’s nose with its sharp claws, the dog does nothing to harm the kitty. On the contrary, it’s watching over the kitty-cat as if it were her own puppy. (Photo by Jessie Pon)

Sheep are herded during the annual sheep parade through Madrid November 2, 2014. Shepherds parade the sheep through the city every year in order to exercise their right to use traditional routes to migrate their livestock from northern Spain to winter grazing pasture land in southern Spain. (Photo by Susana Vera/Reuters)

Roxy, Bono and Blue in costumes inspired by Tim Burton's films in Sonoma County, California, 2014. As Halloween draws closer even pugs are dressing up in costumes. But these outfits are unlikely to give anyone nightmares and are more cute than creepy. Philip Lauer, from California, has dressed his three pets Bono, Blue and Roxy, in adorable costumes – with witch hats and black capes. His home in Sonoma County, California, has its own studio to take professional pictures of the posing pups. Every year he and wife wife Sue dress their pets in creepy costumes and send pictures of them to their friends and family as a spooky treat. (Photo by Phillip Lauer/Barcroft Media)

Hundreds of festive, adorable canines and their owners took part in the annual “A Very Corgi Howloween” costume walk Saturday, October 25, 2014, at Green Lake in Seattle, Wash. The walk was put on by the Seattle-local “Corgi's R Us” MeetUp group. (Photo by Jordan Stead/AP Photo/Seattlepi.com)