Birds sit on the back of a zebra in the Nairobi National Park, near Nairobi, Kenya, November 21, 2018. (Photo by Baz Ratner/Reuters)

Mini-pigs perform during the presentation in Balashikha, Russia on December 19, 2018. (Photo by Maxim Shemetov/Reuters)

A woman walks in central Rason city, northeast of Pyongyang, August 29, 2011. (Photo by Carlos Barria/Reuters)

A man makes a mud oven to be used for baking bread at a workshop in Najaf, south of Baghdad, July 23, 2015. (Photo by Alaa Al-Marjani/Reuters)

Girls ride on a donkey cart with grass for animals on the outside of Nangarhar province, Afghanistan May 19, 2015. (Photo by Reuters/Parwiz)

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

A camel is seen as he is being brought for the foot surgery at the Dubai Camel Hospital in Dubai, UAE, December 11, 2017. (Photo by Satish Kumar/Reuters)

A keeper stands next to llamas during the Annual Stocktake at ZSL London Zoo in London, Britain February 7, 2018. (Photo by Tom Jacobs/Reuters)