A vervet monkey passes in front of a woman on the shores of lake Naivasha, Kenya January 24, 2017. (Photo by Goran Tomasevic/Reuters)

Men slide in the mud during the Boryeong Mud Festival at Daecheon Beach in Boryeong, South Korea, Saturday, July 22, 2017. The 20th annual mud festival features mud wrestling and mud sliding. (Photo by Ahn Young-joon/AP Photo)

Jo-Anne McArthur’s book of photographs puts the spotlight on ethics of zoos around the world. Accompanied by essays by Born Free Foundation’s Virginia McKenna and philosopher Lori Gruen, the images and stories are also shared online through “A Year of Captivity”. Here: Asian Elephant, Denmark, 2016. (Photo by Jo-Anne McArthur/Born Free Foundation/The Guardian)

Clouds gather as walkers pause atop a ridge in Mountain View, California January 7, 2016. (Photo by Noah Berger/Reuters)

Hostesses pose in front of a Suzuki Ignis car at the European Motor Show in Brussels, Belgium, January 13, 2017. (Photo by Francois Lenoir/Reuters)

A boy bursts a soap-bubble at Gorky Park in Moscow on July 19, 2017. (Photo by Mladen Antonov/AFP Photo)

Four-year-old Rashida from Kobani, Syria, part of a new group of more than a thousand immigrants, sleeps as they wait at border line of Macedonia and Greece to enter into Macedonia near Gevgelija railway station August 20, 2015. (Photo by Ognen Teofilovski/Reuters)

French artist Christophe Guinet, also known as “Mr Plant”, works on his plant shoe creation “Wood”, part of the artistic project “Just Grow It”, in his art gallery in Marseille, November 25, 2014. Guinet transforms name-brand Nike sneakers, cult footwear for urban youth, into vegetable compositions, creating a collection of artwork with trainers modified with tree bark, foam and flowers. (Photo by Jean-Paul Pelissier/Reuters)