An American soldier walks ahead of an MKIV (Mark IV) British-made tank, circa 1918. (Photo by Hulton Archive/Getty Images)

In this November 26, 2018 photo, men run during 100 meters athletics competition of the second edition of the Panamanian indigenous games in Piriati, Panama. These games were held in the Embera town of Piriati, some 55 miles (90 kilometers) east of Panama City. (Photo by Arnulfo Franco/AP Photo)

People on inflatable boats enjoy the weather on the Lake Lucerne in Sisikon, Switzerland, August 5, 2018. (Photo by Denis Balibouse/Reuters)

Poshia, 16, who said she is a fashion designer smiles as she holds an umbrella for her relative near princess town, Ghana on November 23, 2018. (Photo by Zohra Bensemra/Reuters)

Meital Ben Ari, a co-founder of “Freedom Farm” pats Gary, a sheep with leg braces, at the farm which serves as a refuge for mostly disabled animals in Moshav Olesh, Israel on March 7, 2019. (Photo by Nir Elias/Reuters)

An Indian sadhu (Hindu holy man) sits on the banks of Sangam – the confluence of the Ganges, Yamuna and mythical Saraswati rivers – on the auspicious bathing day of 'Maghi Purnima' during the Kumbh Mela festival in Allahabad on February 19, 2019. Millions of Hindu pilgrims took the plunge in holy rivers on the most auspicious bathing days of the Kumbh Mela festival, led by naked, ash-smeared holy men and accompanied by chants from Hindu holy texts. (Photo by Sanjay Kanojia/AFP Photo)

A participant takes part in a high heel race to protest in favor of gender equality in Monterrey, Mexico on May 12, 2019. (Photo by Daniel Becerril/Reuters)

Buyan, a male Siberian brown bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, at the Royev Ruchey zoo in Krasnoyarsk, Russia on June 14, 2019. (Photo by Ilya Naymushin/Reuters)