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)

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)

Revellers take part in the Els Enfarinats festival, in the town of Ibi near Alicante, Spain, Saturday December 28, 2019. For about 200-years the inhabitants of Ibi annually celebrate with a battle using flour, eggs and firecrackers, outside the city town hall. (Photo by Alberto Saiz/AP Photo)

Climate change activist Greta Thunberg reacts during a news conference during COP25 climate summit in Madrid, Spain, December 9, 2019. (Photo by Juan Medina/Reuters)

Natural world and wildlife shortlist. Lop Buri in Thailand is home to hundreds of macaques, which local residents consider to be disciples of the Hindu god Hanuman. While some people love them, others fear or even hate them. Despite the inconvenience they often cause, the macaques are generally respected and considered sacred. (Photo by Joan de la Malla/Sony World Photography Awards)

Border Security Force (BSF) soldiers ride their camels as they take part in a rehearsal for a road show ahead of the visit of U.S. President Donald Trump, in Ahmedabad, India, February 21, 2020. (Photo by Amit Dave/Reuters)

A girl looks on after a fire broke out in a slum in Dhaka, Bangladesh, March 11, 2020. (Photo by Mohammad Ponir Hossain/Reuters)

People get covered with powdered colors to celebrate the Holi festival in Bangalore, India on March 21, 2019. Holi is observed at the end of the winter season on the last full moon day of the lunar month Phalguna, which usually falls in the later part of February or March. (Photo by Jagadeesh N.V./EPA/EFE/Rex Features/Shutterstock)