These two young siblings appear to cling on to a tree for dear life and even hold hands as they learn the ropes of climbing, on June 25, 2013. (Photo by Tim Fitzharris/Minden/Solent)

Ary Borges feeds his tiger named Dan at his home in Maringa, Brazil, Thursday, September 26, 2013. Borges is in a legal battle with federal wildlife officials to keep his endangered animals from undergoing vasectomies and being taken away from him. He defends his right to breed the animals and says he gives them a better home than they might find elsewhere in Brazil. (Photo by Renata Brito/AP Photo)

Bangladeshi fisherman feed their otters as they catch fish in Narail some 208 kms from Dhaka on March 11, 2014. The fishermen are using a rare technique that relies on coordination between man and trained otters, a centuries-old fishing partnership that has already long died out in other parts of Asia. (Photo by Munir Uz Zaman/AFP Photo)

Rickshaw drivers wade through a flooded road after heavy rains swept through Guwahati, in the northeastern Indian state of Assam, on June 26, 2014. Seven people have been killed there in flash floods, landslides and heavy rainfall, local media reported Friday. (Photo by Utpal Baruah/Reuters)

A member of Team Chez Victor falls in the water while competing during the Ice Canoe race at the Quebec Winter Carnival in Quebec City, February 5, 2017. (Photo by Mathieu Belanger/Reuters)

Models walk the runway at the Yandy Swim Show during February 2017 New York Fashion Week at Pier 59 on February 14, 2017 in New York City. (Photo by Noam Galai/Getty Images)

A masked reveller poses during the Venice Carnival in Venice, Italy February 17, 2017. (Photo by Alessandro Bianchi/Reuters)

A Hindu holy man, or sadhu, sits beside a fire after smearing his body with ashes at the premises of Pashupatinath Temple, ahead of the Shivaratri festival in Kathmandu, Nepal February 21, 2017. Hindus mark the Maha Shivratri festival by offering special prayers and fasting, with sadhus arriving at Pashupatinath to take part in the event, which takes place on February 24. (Photo by Navesh Chitrakar/Reuters)