“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)

The northern lights, or aurora borealis, appear in the sky over the Bamburgh lighthouse at Stag Rock in Northumberland, England on September 28, 2016. (Photo by Owen Humphreys/PA Wire via ZUMA Press)

A man poses with a hyena along a street in Lagos, Nigeria November 4, 2008. (Photo by Akintunde Akinleye/Reuters)

A soldier supporting anti-government opposition groups carries a rocket-propelled grenade launcher on a street in the Fagah area of Mogadishu, Somalia Sunday, April 25, 2021. Gunfire was exchanged Sunday between government forces loyal to President Mohamed Abdullahi Mohamed, who signed into law on April 14 a two year extension of his mandate and that of his government, and other sections of the military opposed to the move and sympathetic to former presidents Hassan Sheikh Mohamud and Sharif Sheikh Ahmed. (Photo by Farah Abdi Warsameh/AP Photo)

A Buddhist monk wearing a protective mask walks around the Sewu temple during the celebrations of Vesak Day, marking the birth, enlightenment and death of Buddha, amid the coronavirus disease (COVID-19) pandemic in Sleman, Yogyakarta, Indonesia, May 26, 2021. (Photo by Willy Kurniawan/Reuters)

American model Bella Hadid poses as she arrives for the screening of the film “Tre Piani” (Three Floors) at the 74th edition of the Cannes Film Festival in Cannes, southern France, on July 11, 2021. (Photo by Reinhard Krause/Reuters)

A colorful drawing is seen on a wall in Baghdad, Iraq on October 24, 2021. A group of volunteer painters tries to give hope and joy to the Iraqi residents by painting colorful murals on the walls of the houses and streets of the city, tired of violance. Seve-member group named “Butterfly Effect” is busy in drawing paintings to depict life in Baghdad and its cultural heritage on the buildings (Photo by Murtadha Al-Sudani/Anadolu Agency via Getty Images)

Leanna Arcila, 7, is licked by Watson, a therapy dog with the Pawtucket police department, as she receives her COVID-19 vaccination from Dr. Eugenio Fernandez at Nathanael Greene Elementary School in Pawtucket, R.I., Tuesday, December 7, 2021. Even as the U.S. reaches a COVID-19 milestone of roughly 200 million fully-vaccinated people, infections and hospitalizations are spiking, including in highly-vaccinated pockets of the country like New England. (Photo by David Goldman/AP Photo)