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)

Wild elephants, including a tusker (C), rummage through garbage dumped at an open ground in the village of Digampathana in north- central Sri Lanka on August 19, 2017. Sri Lanka has banned the dumping of garbage at open fields and near wildlife reserves, but the practice continues. (Photo by Lakruwan Wanniarachchi/AFP Photo)

Sakakibara Kikai's engineer Go Sakakibara poses with the bipedal robot Mononofu during its demonstration at its factory in Shinto Village, Gunma Prefecture, Japan on April 12, 2018. Developed at Sakakibara Kikai, a maker of farming machinery, LW-Mononofu is a 28-feet tall, two-legged robot weighing in at more than 7 tonnes. It contains a cockpit with monitors and levers for the pilot to control the robot's arms and legs. (Photo by Kim Kyung-Hoon/Reuters)

In this April 13, 2018 photo, motorcycle taxi driver Ricardo Medina, 60, transports vegetable vender Rigoberto Herrera Mendez, left, and coconut vendor Osvaldo Ochoa in Campo Florido, east of Havana, Cuba. The three men expressed hope that new government leadership will improve things, saying the country cannot move backwards. “We survive life with our work”, said Medina. (Photo by Ramon Espinosa/AP Photo)

The front wheels of a tractor lift off the ground as the driver moves a heavy trailer outside Peshawar, Pakistan February 19, 2018. (Photo by Fayaz Aziz/Reuters)

A street entertainer waits for tourists in Havana, Cuba on October 2009. (Photo by Desmond Boylan/Reuters)

Bottles of vintage cognac, with a royal warrant stamp, are seen in storage inside Berry Bros and Rudd wine merchants in central London, Britain, August 21, 2015. Berry Bros. & Rudd, which started as grocers over 300 years ago in St. James's, central London, has two royal warrants. Every year Queen Elizabeth grants about 20 royal warrants, the gold emblem of the British monarchy, in a practice dating back to medieval times. The warrant holders can display the certificate and use the royal coat of arms in their marketing. The warrants lasting five years can help businesses break into new markets overseas, using their role as supplier to the royal family as a gauge of quality. On September 9, Queen Elizabeth will overtake Queen Victoria as Britain's longest-serving monarch. (Photo by Toby Melville/Reuters)

Flames and smoke rising after a fire that broke out in Izmir province of Aegean Turkey on August 19, 2019. Fire brigade crew continue their works. Forest fires have consumed some 500 hectares (over 1,200 acres) of land in Izmir, Turkeys Aegean coast. On Sunday, the fires broke out in four different regions – including two in the southwestern Mugla province and others in Izmir province, according to Agriculture and Forest Ministry. (Photo by Emin Menguarslan/Anadolu Agency via Getty Images)