Xin Xin, a female giant panda, is pictured inside her enclosure at Chapultepec zoo in Mexico City, Mexico May 25, 2018. REUTERS/Ginnette Riquelme 

Xin Xin, a female giant panda, is pictured inside her enclosure at Chapultepec zoo in Mexico City, Mexico May 25, 2018. REUTERS/Ginnette Riquelme 

Xin Xin, a female giant panda, is pictured inside her enclosure at Chapultepec zoo in Mexico City, Mexico May 25, 2018. REUTERS/Ginnette Riquelme 

An attendee dressed in comic character costume vapes as he arrives for the MCM London Comic Con, a convention to celebrate the culture of comic books and related art forms, in London, Britain, May 25, 2018. REUTERS/Toby Melville 

Attendees arrive dressed as their favourite comic characters for the MCM London Comic Con, a convention to celebrate the culture of comic books and related art forms, in London, Britain, May 25, 2018. REUTERS/Toby Melville 

Attendees arrive dressed as their favourite comic characters for the MCM London Comic Con, a convention to celebrate the culture of comic books and related art forms, in London, Britain, May 25, 2018. REUTERS/Toby Melville 

A pig, nearing market weight, stands in a pen at Duncan Farms in Polo, Illinois, U.S. April 9, 2018. Picture taken April 9, 2018. REUTERS/Daniel Acker TPX IMAGES OF THE DAY 

A dog named Golfa, dressed in a Spanish legionnaire costume, is seen after Spanish legionnaires carried a statue of the Christ of Mena outside a church during a ceremony ahead of the Mena brotherhood procession during Holy Week, in Malaga, southern Spain March 29, 2018. REUTERS/Jon Nazca TPX IMAGES OF THE DAY 

Penguins come ashore in Neko Harbour, Antarctica, February 16, 2018. REUTERS/Alexandre Meneghini SEARCH "ANTARCTICA" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. TPX IMAGES OF THE DAY 

A dog is pictured during a training session run at a park, after being collected from an apartment in the upscale neighborhood of Polanco, in Mexico City, Mexico March 2, 2018. REUTERS/Henry Romero 

Revellers wear masks during the traditional Buso Carnival in Mohacs, Hungary, February 11, 2018. REUTERS/Bernadett Szabo 

A cat rests in a street in Istanbul, Turkey, January 15, 2018. REUTERS/Goran Tomasevic SEARCH "TOMASEVIC CATS" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES. 

Pigs are seen on a family farm in Xiaoxinzhuang village, Hebei province, China January 25, 2018. Picture taken January 25, 2018. REUTERS/Dominique Patton 

Pigs are seen on a family farm in Xiaoxinzhuang village, Hebei province, China January 25, 2018. Picture taken January 25, 2018. REUTERS/Dominique Patton 

Pigs are seen on a family farm in Xiaoxinzhuang village, Hebei province, China January 25, 2018. Picture taken January 25, 2018. REUTERS/Dominique Patton 

A dog jumps into the air to catch a ball along the beach near the County Kerry village of Rossbeigh, Ireland, February 4, 2018. REUTERS/Clodagh Kilcoyne TPX IMAGES OF THE DAY 

Clowns and entertainers gather for an annual service of remembrance in honour of British clown Joseph Grimaldi, at All Saints Church in Haggerston, London, Britain February 4, 2018. REUTERS/Simon Dawson 

Sled dogs are tethered before practice for the Aviemore Sled Dog Rally in Feshiebridge, Scotland, Britain January 22, 2018. REUTERS/Russell Cheyne 

A dog in costume walks around San Anton Church in Madrid, Spain, January 17, 2018. Hundreds of pet owners bring their animals to be blessed every year on the day of Saint Anthony, Spain's saint patron of animals. REUTERS/Susana Vera 

An endangered baby high mountain gorilla from the Sabyinyo family plays inside the forest within the Volcanoes National Park near Kinigi, northwestern Rwanda, January 9, 2018. Picture taken January 9, 2018. REUTERS/Thomas Mukoya TPX IMAGES OF THE DAY 

A Bedouin walks with his camel in Zikim beach, on the Mediterranean coast near the southern city of Ashkelon, Israel January 5, 2018. REUTERS/Amir Cohen 

Sherman, the overweight hedgehog, sits in his cage at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sits in his cage at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sniffles leaves at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sits in his cage at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sits behind a plant at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sits on top of a scale displaying the weight of 1477 grams (3.26 lbs) at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Sherman, the overweight hedgehog, sits in his cage at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Zoo worker holds Sherman, the overweight hedgehog, at the Ramat Gan Safari Zoo, near Tel Aviv, Israel January 3, 2018. REUTERS/ Amir Cohen 

Revelers gather in Times Square ahead of the New Year's Eve celebrations in Manhattan, New York, U.S., December 31, 2017. REUTERS/Amr Alfiky 

A small dog wears boots and a coat during frigid weather on Parliament Hill in Ottawa, Ontario, Canada, December 29, 2017. REUTERS/Patrick Doyle TPX IMAGES OF THE DAY 

A dog dressed as Santa Claus takes part in the annual city race in Skopje, Macedonia December 24, 2017.REUTERS/Ognen Teofilovski TPX IMAGES OF THE DAY 

A dog wears a Santa Claus hat as more than a hundred cyclists dressed as Santa Claus meet at the Colosseum in Rome, Italy December 17, 2017. REUTERS/Tony Gentile 

A snowman is seen in the snow in Thames Barrier Park, London, Britain, December 10, 2017. REUTERS/Steven Watt 

German wirehaired dog Rif plays in the snow near Warngau, Germany, December 7, 2017. REUTERS/Michael Dalder 

A Komondor, a traditional Hungarian guard dog, shakes its long fur in Bodony, Hungary, December 6, 2017. REUTERS/Laszlo Balogh TPX IMAGES OF THE DAY 

A Komondor, a traditional Hungarian guard dog, shakes its long fur in Bodony, Hungary, December 6, 2017. REUTERS/Laszlo Balogh 

Bobo, a British Bulldog, takes a shower at The Wagington luxury pet hotel in Singapore December 6, 2017. REUTERS/Edgar Su TPX IMAGES OF THE DAY 

A dog is being washed in a pet shop in Valencia, Spain, December 4, 2017. REUTERS/Heino Kalis 

A visitor carries a dog in a bag at the "Christmas market for the human's best friend" event in Vienna, Austria, December 3, 2017. REUTERS/Leonhard Foeger 

A dog dressed in Santa Claus costume take part in the Santa Claus Run in Budapest, Hungary, December 3, 2017. REUTERS/Laszlo Balogh 

Ural owl (strix uralensis), which is included in Belarus national red data book of endangered birds and animals, rests on a tree branch in Minsk, Belarus November 23, 2017. REUTERS/Vasily Fedosenko TPX IMAGES OF THE DAY 

A remote controlled witch on a broom flies over a Southern California neighborhood after sunset on Halloween night in Encinitas, California, U.S. October 31, 2017. REUTERS/Mike Blake TPX IMAGES OF THE DAY 

Two stag deer pause during a rutt at Bradgate Park in Newtown Linford, Britain October 27, 2017. REUTERS/Darren Staples TPX IMAGES OF THE DAY 

A pair of barn owls looks on at a rehabilitation and conservation centre at the Spier wine estate near Cape Town, South Africa, October 22, 2017. REUTERS/Mike Hutchings TPX IMAGES OF THE DAY 

A baby orangutan looks on at the Singapore Zoo October 19, 2017. REUTERS/Edgar Su TPX IMAGES OF THE DAY 

Anfisa, a 12-year-old female chimpanzee, picks its nose at the Royev Ruchey Zoo in a suburb of the Siberian city of Krasnoyarsk, Russia October 18, 2017. REUTERS/Ilya Naymushin TPX IMAGES OF THE DAY 

A flamingo is seen in a corral before being fitted with an identity ring at a lagoon in the Fuente de Piedra natural reserve, near Malaga, southern Spain, July 29, 2017. REUTERS/Jon Nazca TPX IMAGES OF THE DAY 

Yozhik, a male Himalayan bear, cools down under a stream of water sprayed by an employee in an enclosure on a hot summer day, with the air temperature at about 34 degrees Celsius (93.2 degrees Fahrenheit), at the Royev Ruchey zoo in Krasnoyarsk, Russia June 21, 2017. REUTERS/Ilya Naymushin TPX IMAGES OF THE DAY 

A lion plays with balloons filled with water on a hot day at an amusement park in Yongin, South Korea, June 21, 2017. REUTERS/Kim Hong-Ji TPX IMAGES OF THE DAY 

Boys swim in a stream during a heatwave in Islamabad, Pakistan June 5, 2017. REUTERS/Caren Firouz TPX IMAGES OF THE DAY 

Smoking pipes are seen in a store in Mexico City, Mexico May 12, 2017. REUTERS/Henry Romero 

Smoking pipes are seen in a store in Mexico City, Mexico May 12, 2017. REUTERS/Henry Romero 

Smoking pipes are seen in a store in Mexico City, Mexico May 12, 2017. REUTERS/Henry Romero 

An iced "Unicorn Latte" is pictured at the cafe The End in New York, U.S. May 5, 2017. REUTERS/Lucas Jackson 

A barista creates 3D latte art on a cup of iced coffee at a cafe in Singapore May 5, 2017. REUTERS/Edgar Su 

A barista creates 3D latte art of cats on a cup of iced coffee at a cafe in Singapore May 5, 2017. REUTERS/Edgar Su 

Bats are seen in the Old City in Caesarea, Israel, April 26, 2017 REUTERS/Amir Cohen 

A donkey brays before the procession of the "Virgem da Atalaia" during Holy Week in Alcochete, near Lisbon, Portugal April 16, 2017. REUTERS/Rafael Marchante 

A Staffordshire Terrier wearing a muzzle looks out of a car in Krasnoyarsk, Russia, April 14, 2017. REUTERS/Ilya Naymushin TPX IMAGES OF THE DAY