This family of warthogs regularly visited our campsite in the Ethiopian highlands so I set up a remote camera with a wide-angle lens to photograph them as they rummaged around for food. They just had a mud bath. (Photo by Will Burrard-Lucas/Caters News Agency)

“Left behind” children Luo Hongni, 11 (L) and brother Luo Gan,10, carry flowers to be used as feed while doing chores in the fields on December 18, 2016 in Anshun, China. Like millions of Chinese children, the four Luo siblings are being raised by their grandparents in rural China as their parents left to find work in urban areas. (Photo by Kevin Frayer/Getty Images)

The Flying Bull's P-38 Lockheed Lightning N25Y / 13 – Red Bull – Flying Legends Airshow 2012 Duxford (Photo by Rob Lovesey)

A man dressed as a devil poses next to a grafitti of late rebel hero Ernesto "Che" Guevara in the indigenous community of Monimbo in Masaya, Nicaragua, October 16, 2015. People prepare to participate in the popular annual festival called "The Aguizotes" held on the last Friday of October, where residents dress up as characters from legends and folklore mythology of Nicaragua. (Photo by Oswaldo Rivas/Reuters)

Children exercise before a wrestling practice session at an old Basque ball game gymnasium in downtown Havana, October 30, 2014. (Photo by Alexandre Meneghini/Reuters)

Angela Griffin attends the UK premiere of Hop held at The Vue west end on March 20, 2011 in London, England.

Alkar Vito runs during the Children's Alka competition in Vuckovici village, Croatia, August 23, 2015. Children's Alka is a tournament which has been held every August in the Croatian village of Vuckovici since 1955, commemorating the victory over the Ottoman Turkish administration. The tournament is named after the ring, Alka, which children have to hit with their spears. (Photo by Antonio Bronic/Reuters)

Fans dressed as movie Star Wars characters pose as they cerebrate the Star Wars Day in Taipei, Taiwan, Wednesday, May 4, 2016. May 4 is known as Star Wars Day among fans worldwide since the date sounds phonetically similar to the franchise's slogan, “May the Force Be With You”. (Photo by Chiang Ying-ying/AP Photo)