In this April 2, 2015 photo, dog owner Laura Aquilina strolls with her two year old Rottweiler Brutus, who was recently fitted with prosthetics on all four paws, and is currently learning to use them, near Aquilina's home in Loveland, Colo. Brutus lost all four paws to frostbite as a puppy while under care of a breeder, and Aquilina began caring for him about a year ago. (Photo by Brennan Linsley/AP Photo)

Nova Scotia Duck Tolling retriever Torrey competes in the 10th annual Petco Unleashed surfing dog contest at Imperial Beach, California August 1, 2015. Proceeds raised at the event go to benefit the San Diego Humane Society. (Photo by Mike Blake/Reuters)

People ride a motorcycle near Koudoukou Mosque where Pope Francis meets Imam Tidiani Moussa Naibi in Bangui, Central African Republic, November 30, 2015. (Photo by Stefano Rellandini/Reuters)

Playboy Bunnies pose for a selfie at the premiere of “The Transporter Refueled” at Playboy Mansion in Los Angeles, California August 25, 2015. The movie opens in the U.S. on September 4. (Photo by Mario Anzuoni/Reuters)

A policer officer hits a man with a baton as he tries to maintain order while migrants wait for trains at a temporary camp near Gevgelija, Macedonia, September 7, 2015. Several thousand migrants in Macedonia boarded trains on Sunday to travel north after spending a night in a provisional camp. Macedonia has organised trains twice a day to the north border where migrants cross into Serbia to make their way to Hungary. Since June, Macedonian authorities have said that more than 60,000 migrants have entered the country, and around 1,500 entered just in one day, mainly refugees from Syria. (Photo by Stoyan Nenov/Reuters)

An activist takes a selfie during a protest ahead of the 2015 Paris Climate Conference, in Paris, Sunday, November 29, 2015. More than 140 world leaders are gathering around Paris for high-stakes climate talks that start Monday, and activists are holding marches and protests around the world to urge them to reach a strong agreement to slow global warming. (Photo by Christophe Ena/AP Photo)

A resident walks past big waves spilling over a wall onto a coastal road in the city of Legaspi in Albay province, south of Manila on December 14, 2015, as typhoon Melor approaches the city. More than 700,000 people fled the central Philippines amid threats of giant waves, floods and landslides as powerful Typhoon Melor approached the archipelago nation, officials said December 14. (Photo by Charism Sayat/AFP Photo)

A Ukrainian woman begs Ukrainian President Petro Poroshenko to stop the bombing in Donetsk after shell hit the residential area where she lives, killing two civilians in Donetsk's Kyibishevsky district, on January 29, 2015. (Photo by Manu Brabo/AFP Photo)