“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 woman leaves with her television set, as she and others are evicted from their apartment blocks close to the site of last week's building collapse, after their homes were deemed unfit for habitation and marked for demolition, in the Huruma neighborhood of Nairobi, Kenya Friday, May 6, 2016. Following a building collapse which claimed at least 40 lives with more 80 people still unaccounted for, after severe flooding, the government has ordered the demolition of similar unsafe buildings in the area. (Photo by Ben Curtis/AP Photo)

A general view of dried-up rivers in the Pilbara region of Western Australia December 2, 2013. Western Australia's Pilbara region, which is the size of Spain, has the world's largest known deposits of iron ore and supplies nearly 45 percent of global trade in the mineral. (Photo by David Gray/Reuters)

“Basunga”. Basunga (3 weeks-old newborn with albinism) is happily sleeping with his cousin. For now, he does not yet realize the difficulties he will face to integrate into the Congolese society as a PWA. The success of his integration will greatly depends of how he accepts himself and his skin condition a and how educated he will be. Photo location: Kinshasa, Congo RDC. (Photo and caption by Patricia Willocq/National Geographic Photo Contest)

“Sperm whale opening it's huge mouth, Ogasawara Islands, Japan. Sperm whales are the biggest carnivorous animals on the planet. Each teeth in the mouth of adult specimen weights more than 1 kilogram. Interestingly enough that modern marine biologists believe that these teeth despite being fearsome play little role in capturing and eating giant squid – with their main function being mainly ritual aggression between males!”. (Photo by Alexander Safonov)

Sebastião Salgado is a Brazilian documentary photographer living in Paris. He has produced several books, and his work has been exhibited extensively around the world. His latest work, «Genesis», premieres at The Natural History Museum in London on April 11, on view through September 8, 2013. Photo: On South Georgia, a barren island in the far South Atlantic, a pair of southern elephant seal calves beckon before a colony of king penguins. “The male seals can grow to almost five tons,” says Salgado, “but these are just babies. This one looked at me with beautiful eyes”. (Photo by Sebastião Salgado/Amazonas/Contact Press Images)

A Russian prisoner eating bread. (Photo by Hulton Archive/Getty Images). Finland, circa 1940

File photo dated 21/04/66 of Pattie Boyd in London's West End wearing a mini skirt, as the British designer Mary Quant, widely credited with popularising the mini skirt has recalled its “feeling of freedom and liberation” 50 years after she took the fashion world by storm. Quant, who named the skirt after her favourite make of car, said she “couldn't have imagined” in 1964 that it would become a staple of women's clothing, but added: “It seemed then to be obvious, and so right”. (Photo by PA Wire)