The three orangutans at Pairi Daiza zoo, Belgium, developed a “special bond” with the otters after their river was run through the ape enclosure on March 2020. The zoo said it enriched both species’ environments. An animal – and this is even more the case of orangutans, with whom humans share 97 per cent of their DNA – must be entertained, occupied, challenged and kept busy mentally, emotionally and physically at all times. (Photo by Pascale Jones/The Sun)

A donkey savors warming temperatures after a long winter at the zoo in Warsaw, Poland, on Wednesday, April 8, 2015. (Photo by Czarek Sokolowski/AP Photo)

Circus artists perform at the International Circus Show started in Avenue Habib Bourguiba in Tunis, Tunisia on June 23, 2022. (Photo by Yassine Gaidi/Anadolu Agency via Getty Images)

Grumpy Cat attends the “Grumpy Cat: A Grumpy Book” Book Event at Bookends Bookstore on October 16, 2013 in Ridgewood, New Jersey. (Photo by Michael N. Todaro/WireImage)

Turkana tribesmen walk with guns to protect their cattle from rival tribes near Baragoy, Kenya August 4, 2017. (Photo by Goran Tomasevic/Reuters)

Bonobo apes, primates unique to Congo and humankind's closest relative, groom one another at a sanctuary just outside the capital Kinshasa, Congo on October 31, 2006. (Photo by Finbarr O'Reilly/Reuters)