A tribal fighter loyal to Yemen's government stands in Al Khurais village of Nihm district east of the capital Sanaa January 11, 2016. (Photo by Ali Owidha/Reuters)

An incredible clear-air lightning display from storms to the east of Noonamah, just outside Darwin on April 6, 2015. (Photo by Jacci Ingham/The Guardian)

In this photograph taken on December 8, 2017, Indian child Samarth Bangari, 2, plays with langur monkeys at his home in Allapur in India' s southwest Karnataka state, 250 miles from Bangalore. He is still too young to talk, but a 2- year- old Indian boy has become a subject of local intrigue after befriending a gang of langur monkeys. (Photo by Manjunath Kiran/AFP Photo)

Competitors release their hens during the World Championship Hen Racing Championships in Bonsall, Britain August 1, 2015. (Photo by Darren Staples/Reuters)

HRP-4C, a five-foot humanoid robot developed at Japan's National Institute of Advanced Industrial Science and Technology, sings and dances with performers at the Digital Contents Expo in Tokyo on October 17, 2010. The robot runs entertainment software called Choreonoid, a name formed from the words “choreograph” and “humanoid”. (Yoshikazu Tsuno/AFP)

Dutch artist Maxim Gazendam works on his sand sculpture during the third edition of the European Championship Sand Sculpting 2014 in Zandvoort aan Zee, The Netherlands, 08 August 2014. Eight sculptors from different European countries will each create an impressive sculpture on the main theme “Music and Dance”. (Photo by Remko De Waal/EPA)

Cadets from the National Cadet Corps (NCC) celebrate after being awarded the first position in the best marching trophy competition during the Republic Day celebrations in the northern Indian city of Chandigarh January 26, 2015. (Photo by Ajay Verma/Reuters)

The social media star Demi Rose, 23, wows her fans and showed off her famous curves as she poses in a thong bikini and high heels for “I Saw It First” in Ibiza, Spain on Monday, June 4, 2018. (Photo by KP Pictures)