The Villarrica Volcano is seen at night in Chile, April 16, 2016. Villarrica is one of Chile's most active volcanoes. Picture taken with long exposure. (Photo by Cristobal Saavedra/Reuters)

People take pictures with their mobile phone of a scale model of a dinosaur displayed in front of La Sapienza University headquarters in Rome April 10, 2015. The realistic reproductions of dinosaurs are part of the “Dinosaurs in the flesh, science and art bring to life the rulers of a lost world” exhibition. (Photo by Alessandro Bianchi/Reuters)

A donkey savors warming temperatures after a long winter at the zoo in Warsaw, Poland, on Wednesday, April 8, 2015. (Photo by Czarek Sokolowski/AP Photo)

Mercedes Formula One driver Lewis Hamilton of Britain sprays champagne at a grid girl as he celebrates his victory on the podium after the Chinese F1 Grand Prix at the Shanghai International Circuit, April 12, 2015. (Photo by Carlos Barria/Reuters)

Cheng Chen (R), a 27-year-old worker at a state-owned enterprise, poses for a photograph with his nephew who is wearing his home-made Iron Man armour, in Xuzhou, Jiangsu province April 13, 2015. It cost Cheng about 500 yuan ($81 USD) to make the armour, which weighs about 4 kilograms, with plastic boards and LED lights, local media reported. (Photo by Reuters/Stringer)

A woman eats candy in the shape of a phallus during the Kanamara Matsuri, or Iron Phallus Festival through a street near the Kanamara shrine in Kawasaki outside of Tokyo April 5, 2015. The festival celebrates fertility and is used to raise awareness and money for the prevention of sexually transmitted diseases. (Photo by Thomas Peter/Reuters)

Star Wars actors on the Cantina set at Star Wars Celebration: The Ultimate Fan Experience held at the Anaheim Convention Center on Thursday, April 16, 2015, in Anaheim, Calif. (Photo by Richard Shotwell/Invision/AP Photo)

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)