“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)

“Double head vulture”. On the day of windy days during raptors migration some people in my country start to catch these tired raptors, so in this day we go to photograph some raptors and we saw these tow tired vultures, so we start to drag them away from the hunters until they reach a good hidden place, to make them safe until they start a new journey. Photo location: Kuwait. (Photo and caption by Mohd Khorshed/National Geographic Photo Contest)

“Cassowaries are large, flightless birds related to emus and (more distantly) to ostriches, rheas, and kiwis”, writes Olivia Judson in the September issue of National Geographic magazine. How large? People-size: Adult males stand well over five foot five and top 110 pounds. Females are even taller, and can weigh more than 160 pounds. Dangerous when roused, they’re shy and peaceable when left alone. But even birds this big and tough are prey to habitat loss. The dense New Guinea and Australia rain forests where they live have dwindled. Today cassowaries might number 1,500 to 2,000. And because they help shape those same forests – by moving seeds from one place to another – “if they vanish”, Judson writes, “the structure of the forest would gradually change” too. (Photo by Christian Ziegler/National Geographic)

“The Independence day”. While on storm chasing expeditions in the Tornado Alley in USA I have encountered many photogenic supercell storms. This photograph was taken while we were approaching the storm near Julesburg, Colorado on My 28th, 2013. The storm was tornado warned for more than one hour, but stayed an LP storm through all its cycles and never produced a tornado, just occasional brief funnels, large hail and some rain. Photo location: Julesburg, Colorado, USA. (Photo and caption by Marko Korošec/National Geographic Photo Contest)

This 1972 VW Beetle was one of over 150 cars at the eighth annual historic U.S Route 40 Mini-Nationals car show held on Sunday at Tecumseh high school. (Photo by Marshall Gorby/AP Photo)

1st Place in Wildlife: A male orangutan peers from behind a tree while crossing a river in Borneo, Indonesia. (Photo by Jayaprakash Joghee Bojan/National Geographic Nature Photographer of the Year contest 2017)

Uranjargal, a leader of the Mongolian neo-Nazi group Tsagaan Khass, stands next to a statue of Chingunjav, a Mongolian national hero, in Ulan Bator June 22, 2013. The group has rebranded itself as an environmentalist organisation fighting pollution by foreign-owned mines, seeking legitimacy as it sends Swastika-wearing members to check mining permits. Over the past years, ultra-nationalist groups have expanded in the country and among those garnering attention is Tsagaan Khass, which has recently shifted its focus from activities such as attacks on women it accuses of consorting with foreign men to environmental issues, with the stated goal of protecting Mongolia from foreign mining interests. This ultra-nationalist group was founded in the 1990s and currently has 100-plus members. (Photo by Carlos Barria/Reuters)

A cameraman films “Diana And Callisto” (circa 1556-59) oil painting by Venetian artist Titian as it goes on display for the first time at the National Gallery on March 1, 2012 in London, England.(Photo by Dan Kitwood/Getty Images)