“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)

What would superheroes do if they had a part time job? Well… besides fighting crime, the powers of most superheroes aren’t exactly very useful. Sure, Flash would make a great delivery boy, delivering the freshest pizza in the world, while Thor might turn out to be a great smith (though judging by the way he handles his mallet, it is very unlikely), but in the end of the day, all these things are pretty useless. It sure is hard being a superhero when you have no villains to catch; especially if the only superpower that you have is lighting yourself on fire. Reducing you to a mere job of being used as fuel for cooking grilled chicken. Besides, it’s not exactly useful for catching villains either, if you don't plan on burning them alive… (Photo by Chow Hon Lam)

US MotoGP rider Nicky Hayden of the Aspar MotoGP team performs a wheelie during third free practice session for the motorcycle GP in Montmelo, Spain, Saturday, June 13, 2015. The Catalunya Grand Prix will take place on Sunday in Montmelo. (AP Photo/Manu Fernandez)

In this April, 2015, photo provided by DC Shoes, daredevil Robbie Maddison in his latest stunt rides his motorcycle across waves in Tahiti, French Polynesia, using ski-like devices on his wheels. (Photo by Tim McKenna/DC Shoes via AP Photo)

Members of La Legion, an elite unit of the Spanish Army, including a goat they use as a pet wait for the start of a military parade as they celebrate a holiday known as “Dia de la Hispanidad” or Hispanic Day in Madrid, Wednesday, October 12, 2016. (Photo by Daniel Ochoa de Olza/AP Photo)

People walk past the Sleepwalker, a sculpture along the High Line in New York, US on May 10, 2016. The hyperrealistic work by Brooklyn artist Tony Matelli is part of the linear park’s Wanderlust exhibition. (Photo by Xinhua/Barcroft Images)

A motorcycle carrying protesters holding a placard using the acronym of the national electoral commission, drives ahead of demonstrators on foot calling for the disbandment of the commission over allegations of bias and corruption, in downtown Nairobi, Kenya Monday, June 6, 2016. (Photo by Ben Curtis/AP Photo)

A string is used to ensure that the skirts of female members of the honour guard are in the same height from the ground as they prepare for a welcoming ceremony for Congo Republic President Denis Sassou Nguesso outside the Great Hall of the People in Beijing, China, July 5, 2016. (Photo by Jason Lee/Reuters)