A serviceman walks near an APC while a helicopter flies on the position of the Ukrainian troops in Donetsk region on August 9, 2014. Fighting with pro-Russian separatists in eastern Ukraine has left 13 troops dead in the last 24 hours, Ukraine's military said Saturday. (Photo by Anatolii Stepanov/AFP Photo)

A U.S. Army soldier with the 10th Special Forces Group and his military working dog jump off the ramp of a CH-47 Chinook helicopter from the 160th Special Operations Aviation Regiment during water training over the Gulf of Mexico as part of exercise Emerald Warrior 2011 on March 1, 2011. (Photo by Tech. Sgt. Manuel J. Martinez/U.S. Air Force)

Gas-masked men of the British Machine Gun Corps with a Vickers machine gun during the first battle of the Somme, 1916. (Photo by General Photographic Agency/Getty Images)

Visitors are seen with giraffes on a bus at Safari Park in Kanchanaburi Province, Thailand, January 19, 2020. Kanchanaburi in western Thailand an area known for its waterfalls and caves. (Photo by Rachen Sageamsak/Xinhua News Agency/Eyevine)

An Extinction Rebellion activist takes part in a protest in Berlin, Germany on October 5, 2020. (Photo by Michele Tantussi/Reuters)

A girl walks an Akita-inu dog dressed in a military uniform in Vladivostok, Russia on April 9, 2019. (Photo by Yuri Smityuk/TASS)

WrestlerTeddy Sheedi (L) fights his opponent during the traditional Sindhi Malakhra wrestling in Karachi, Pakistan, 13 December 2020. A Malakhra match begins with both wrestlers tying a twisted cloth around the opponent's waist. Each one then holds onto the opponent's waistcloth and tries to throw him to the ground. (Photo by Shahzaib Akber/EPA/EFE)

Luke Jerram's “Museum of the Moon” at English Heritage's Illuminating Rievaulx installation at Rievaulx Abbey, near Helmsley, North Yorkshire, England on September 18, 2019. (Photo by Danny Lawson/PA Images via Getty Images)