“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)

A reveler jumps from a fountain onto the crowd below, after the launch of the “Chupinazo” rocket, to celebrate the official opening of the 2014 San Fermin fiestas in Pamplona, Spain, Sunday, July 6, 2014. Revelers from around the world turned out here to kick off the festival with a messy party in the Pamplona town square, one day before the first of eight days of the running of the bulls glorified by Ernest Hemingway's 1926 novel “The Sun Also Rises”. (Photo by Andres Kudacki/AP Photo)

«Little Red Riding Hood». “The moment I pulled this sweater out of the drawer for Frankie I knew what I wanted for my picture today. I envisioned the look, the style, and the composition. When working with a 2 year old it is never easy to actually get the shot you want, especially when they decide to skip nap time. But I really like how this one turned out” – Rich. (Photo by Rich)

Female North Korean traffic police officers gather in front of bronze statues of the late leaders Kim Il Sung and Kim Jong Il to pay their respects in Pyongyang, North Korea on Saturday, February 16, 2013. North Koreans turned out to commemorate what would have been the 71th birthday of Kim Jong Il who died on December 17, 2011. (Photo by David Guttenfelder/AP Photo)

Members of the 1st Tennessee wait to take part in in a demonstration of a battle during ongoing activities commemorating the 150th anniversary of the Battle of Gettysburg, Friday, June 28, 2013, at at Bushey Farm in Gettysburg, Pa. Union forces turned away a Confederate advance in the pivotal battle of the Civil War fought July 1-3, 1863, which was also the war's bloodiest conflict with more than 51,000 casualties. (Photo by Matt Rourke/AP Photo)

A cat with a “stegosaurus spine” design cut into its fur is seen next to a dog at a pet shop, in Tainan, Taiwan June 19, 2016. Lee Mei-chen, Taiwanese hairdresser turned pet groomer, shaves paw prints, lion faces and characters from Japanese brand Hello Kitty on to animal backs. The teddy bear design is one of the most complex in the furry repertoire. Photo by Tyrone Siu/Reuters)

In this October 24, 2010 file photo, Canadian-born actress Pamela Anderson poses for photographers during a photocall to unveil a new advertisement in aid of People for the Ethical Treatment of Animals (PETA) in London to encourage people to go vegetarian. PETA turns 35 years old in 2015, is the largest animal rights group in world with 3 million members, and has done a lot with a little s*x, shock and celebrity. (Photo by Akira Suemori/AP Photo)

Rooftops of solar powered houses are pictured in Ota, 80 km northwest of Tokyo in this October 28, 2008 file photo. One by one, Japan is turning off the lights at the giant oil-fired power plants that propelled it to the ranks of the world's top industrialised nations. With nuclear power in the doldrums after the Fukushima disaster, it's solar energy that is becoming the alternative. Solar power is set to become profitable in Japan as early as this quarter, according to the Japan Renewable Energy Foundation (JREF), freeing it from the need for government subsidies and making it the last of the G7 economies where the technology has become economically viable. (Photo by Yuriko Nakao/Reuters)