A zebra rubs its head against another at London Zoo, London, Britain, August 22, 2019. REUTERS/Toby Melville 

Siberian tigers bathe in a pool to cool down at Al Zawra zoo in Baghdad, Iraq, June 29, 2019. Picture taken June 29, 2019. REUTERS/Thaier al-Sudani 

People sit in St James’s Park during sunny weather in London, Britain, June 1, 2019 REUTERS/Kevin Coombs 

Transgender rights activist waves a transgender flag as they protest the killings of transgender women this year, at a rally in Washington Square Park in New York, U.S., May 24, 2019. REUTERS/Demetrius Freeman 

One of three newborn white Bengal tiger cubs is pictured with its mother in La Pastora Zoo in the municipality of Guadalupe, Mexico April 25, 2019. REUTERS/Daniel Becerril TPX IMAGES OF THE DAY 

Three newborn white Bengal tiger cubs are pictured with their mother in La Pastora Zoo in the municipality of Guadalupe, Mexico April 25, 2019. REUTERS/Daniel Becerril 

Three newborn white Bengal tiger cubs are pictured with their mother in La Pastora Zoo in the municipality of Guadalupe, Mexico April 25, 2019. REUTERS/Daniel Becerril 

The queen bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica 

Bees are seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica 

The queen bee is seen on the frame of a hive in a village of Ripanj near Belgrade, Serbia, April 9, 2019. Picture taken April 9, 2019. REUTERS/Marko Djurica 

Birds sit on the back of a zebra in the Nairobi National Park, near Nairobi, Kenya, November 21, 2018. REUTERS/Baz Ratner TPX IMAGES OF THE DAY 

Bees come in and out from a beehive at beekeeper Leonid Baranenko's bee-garden in the village of Mikhaylovka, Belarus June 24, 2017. Picture taken June 24, 2017. REUTERS/Vasily Fedosenko TPX IMAGES OF THE DAY 

Bees are seen on a beehive frame with honeycomb filled with honey at beekeeper Leonid Baranenko's bee-garden in the village of Mikhaylovka, Belarus June 24, 2017. Picture taken June 24, 2017. REUTERS/Vasily Fedosenko 

Bees are seen on beehive frames with honeycombs at beekeeper Leonid Baranenko's bee-garden in the village of Mikhaylovka, Belarus June 24, 2017. Picture taken June 24, 2017. REUTERS/Vasily Fedosenko 

Sandstone sculpted by water and wind erosion is seen in a slot canyon, one of hundreds that surround Lake Powell near Page, Arizona, May 26, 2015. Lake Powell on the Colorado River provides water for Nevada, Arizona and California. A severe drought in recent years, combined with withdrawals that many believe are not sustainable, has reduced its levels to only about 42 percent of its capacity. REUTERS/Rick Wilking PICTURE 6 OF 26 FOR WIDER IMAGE STORY "EARTHPRINTS: LAKE POWELL"SEARCH "EARTHPRINTS POWELL" FOR ALL IMAGES TPX IMAGES OF THE DAY

A man takes his jacket off as he settles into his deck chair on a sunny day in St. James Park in London, Britain June 24, 2015. REUTERS/Suzanne Plunkett 

A man sits in a deck chair on a sunny day in St. James Park in London, Britain June 24, 2015. REUTERS/Suzanne Plunkett TPX IMAGES OF THE DAY

ATTENTION EDITORS: SPANISH LAW REQUIRES THAT THE FACES OF MINORS ARE MASKED IN PUBLICATIONS WITHIN SPAIN Women wearing sevillana dresses are seen during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville, southern Spain, April 23, 2015. The fair will run until April 26. REUTERS/Marcelo del Pozo

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse ,The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse , The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse , The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse, The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman TPX IMAGES OF THE DAY

Aerial view of flower fields near the Keukenhof park, also known as the Garden of Europe, in Lisse, The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse, The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

An aerial view of flower fields is seen near the Keukenhof park, also known as the Garden of Europe, in Lisse, The Netherlands April 15, 2015. Keukenhof, employing some 30 gardeners, is considered to be the world's largest flower garden displaying millions of flowers every year. REUTERS/Yves Herman

Women relax on deckchairs during hazy sunshine in Hyde Park in central London April 10, 2015. Local media reports that southeastern England could reach the highest level of air pollution today. REUTERS/Toby Melville 

A close-up view of Indian Prime Minister Narenda Modi's dark pinstripe suit, repeatedly embroidered with the words "Narendra Damodardas Modi", as he talks to U.S. President Barack Obama while walking through the garden at Hyderabad House in New Delhi January 25, 2015. Modi gave U.S. first lady Michelle Obama stiff fashion competition at the weekend, turning out in a dark pinstripe suit embroidered with his own name - repeatedly. Damodardas was Modi's father, a tea seller in western Indian state of Gujarat. Picture taken January 25, 2015. To match story INDIA-OBAMA/FASHION REUTERS/Jim Bourg (INDIA - Tags: POLITICS FASHION) 

Sumatran tiger cubs and their parents walk around their enclosure at London Zoo in London, January 5, 2015. The annual stock take and animal count, a requirement of London Zoo's license, included additions to the international conservation breeding programme such as the three tiger cubs and Philippine crocodiles. REUTERS/Toby Melville (BRITAIN - Tags: ANIMALS TPX IMAGES OF THE DAY) 

A taxi driver is silhouetted as she passes a poured paint public artwork by artist Ian Davenport in central London July 2, 2014. REUTERS/Luke MacGregor (BRITAIN - Tags: SOCIETY TRANSPORT) 

Colombian musicians stand before an urn containing the ashes of Colombian Nobel laureate Gabriel Garcia Marquez during a public viewing in the Palace of Fine Arts in Mexico City April 21, 2014. Fans and family paid their respects to Garcia Marquez on Monday, leaving flowers and playing music in remembrance of the Nobel laureate and giant of Latin American literature. Hundreds thronged outside Palace of Fine Arts to lay bouquets and see the urn containing the ashes of the author of "One Hundred Years of Solitude," who died in Mexico on April 17, 2014, at age 87. REUTERS/Edgard Garrido (MEXICO - Tags: SOCIETY OBITUARY) 

Women walk on a pedestrian cross in central Shanghai April 8, 2014. REUTERS/Aly Song (CHINA - Tags: SOCIETY TPX IMAGES OF THE DAY) 

Muslims pray and read the Koran at the Al-Masjid al-Nabawi (The Mosque of the Prophet) before the early morning prayer of al-Fajr in the holy city of Medina January 16, 2014. Muslims marked Eid Mawlid al-Nabawi, or the birth of Prophet Mohammad, on January 14. REUTERS/Amr Abdallah Dalsh (SAUDI ARABIA - Tags: RELIGION) 

A pedestrian walks by a fence outside Number One Regional Tuberculosis Hospital of the General Directorate of the Russian Federal Penitentiary Service, in Russia's Siberian city of Krasnoyarsk November 15, 2013. Pussy Riot punk band member Nadezhda Tolokonnikova has asked Russia's Supreme Court to throw out her conviction and two-year prison sentence, her lawyer Irina Khrunova said on Thursday. Tolokonnikova, 24, started a hunger strike in September, demanding a transfer from a prison where she said that a official had threatened her life and that inmates faced inhumane conditions including 17-hour work days. Prison authorities said on October 18 that Tolokonnikova would be moved, and Khrunova said there were indications she had been transferred to a prison in Siberia, about 3,600 km (2,250 miles) east of Moscow, but that she was unable to confirm it. According to local media on November 14, Tolokonnikova was escorted to Krasnoyarsk' s Number One Regional Tuberculosis Hospital. REUTERS/Ilya Naymushin (RUSSIA - Tags: CRIME LAW RELIGION ENTERTAINMENT HEALTH) 

Malaysian youths wave national flags during National Day celebrations marking the 56th anniversary of the country's independence, at Independence Square in Kuala Lumpur August 31, 2013. REUTERS/Bazuki Muhammad (MALAYSIA - Tags: ANNIVERSARY POLITICS SOCIETY TPX IMAGES OF THE DAY) 

A one-month-old zebra stands next to its mother in their enclosure at Planckendael's zoo near Mechelen August 20, 2013. REUTERS/Francois Lenoir (BELGIUM - Tags: ANIMALS) 

A boy takes a picture with a Soviet-made film camera of an art installation on a bank of the Yenisei River in the village of Ovsyanka, some 24km (15 miles) south of Russia's Siberian city of Krasnoyarsk, August 17, 2013. REUTERS/Ilya Naymushin (RUSSIA - Tags: SOCIETY TPX IMAGES OF THE DAY) 

Workers harvest asparagus in the field of an asparagus farm in Preschen near Cottbus May 1, 2013. Germans are famed for their love of white asparagus rather than the more common green variety. Some 90-95 percent of consumption in Germany is of white asparagus, which must be grown deep in the soil and dug out by hand. REUTERS/Michaela Rehle (GERMANY - Tags: AGRICULTURE ENVIRONMENT TPX IMAGES OF THE DAY) 

A woman carries her puppy at a cafe in the Gangnam area of Seoul October 3, 2012. Gangnam is the most upmarket neighbourhood in the South Korean capital. Known as Seoul's "Beverly Hills", its streets are lined with designer-brand shops and trendy bars and restaurants. Chubby South Korean singer Psy was raised in the area and his hit song "Gangnam Style", with his quirky horse-riding dance, has stormed to number one in charts around the world while the video has been watched more than 454 million times on YouTube since July. Picture taken October 3, 2012. REUTERS/Lee Jae-Won (SOUTH KOREA - Tags: ANIMALS ENTERTAINMENT SOCIETY) 

Khan, a 2-year-old male Bengali white tiger, is seen inside a cage at the Royev Ruchey zoo in Russia's Siberian city of Krasnoyarsk September 26, 2012. REUTERS/Ilya Naymushin (RUSSIA - Tags: ANIMALS SOCIETY) 

A woman rides her bicycle on a road in Jaffna September 10, 2012. REUTERS/Dinuka Liyanawatte (SRI LANKA - Tags: SOCIETY TRANSPORT) 

Men prepare a tent for a performance at a circus in Lahore May 17, 2012. REUTERS/Mohsin Raza (PAKISTAN - Tags: SOCIETY) 

A woman wearing a typical Sevillana outfit is seen in the traditional Feria de Abril (April fair) in the Andalusian capital of Seville April 25, 2012. REUTERS/Javier Diaz (SPAIN - Tags: SOCIETY) 

A man is seen silhouetted through fabric as he constructs a temporary shelter at a transit camp for villagers who have been displaced in Jagatsinghpur district, about 75 km (46 miles) east of Orissa's state capital Bhubaneswar, June 22, 2011. Local protests have forced the poor eastern state of Orissa to halt acquiring land for a proposed $12 billion steel plant to be built by South Korea's POSCO, further delaying the biggest foreign direct investment in Asia's third largest economy. Farmers accuse the Orissa state government of being in cahoots with big business to trick them out of land their families have held for generations. Picture taken June 22, 2011. To match Feature INDIA-POSCO/ REUTERS/Vivek Prakash (INDIA - Tags: POLITICS CIVIL UNREST BUSINESS SOCIETY) 

Sun chairs are prepared for visitors during the opening day at Berlin's Wannsee lido, April 22, 2011. REUTERS/Tobias Schwarz (GERMANY - Tags: ENVIRONMENT SOCIETY IMAGES OF THE DAY) 

A close-up view shows an eye of a zebra at the zoo in Cali March 24, 2011. REUTERS/Jaime Saldarriaga (COLOMBIA - Tags: ANIMALS) 

A pink and red inside-out long jacket with stripy white sleeves designed by Yohji Yamamoto from his Autumn/Winter 2009-10 collection is displayed at the V&A, in London March 10, 2011. The Yohji Yamamoto retrospective exhibition, which showcases over 80 women's and menswear garments, runs from March 12 to July 10, 2011. REUTERS/Suzanne Plunkett (BRITAIN - Tags: FASHION ENTERTAINMENT) 

A man rides an escalator outside a railway station in Tachikawa, western Tokyo November 30, 2010. REUTERS/Yuriko Nakao (JAPAN - Tags: SOCIETY) 

Actors dressed as elves, in a promotion for office supply retailer OfficeMax, walk on the floor of the New York Stock Exchange, November 23, 2010. REUTERS/Brendan McDermid (UNITED STATES - Tags: BUSINESS ODDLY) 

A miniature orchid, masdevallia striatella, which is a native species unique in Costa Rica, is seen on display at the Lankester Botanical Garden in Paraiso de Cartago, west of San Jose October 28, 2010. According to Robert Dressler, the botanical garden's biologist, there are nearly 800 species of miniature orchids grown in this garden, of which 90% are endemic. The miniature orchid collection is one of the largest in the world. REUTERS/Juan Carlos Ulate (COSTA RICA - Tags: ENVIRONMENT SOCIETY) 

A visitor wears an airplane lapel pin at Farnborough Airshow in southern England, July 22, 2010. REUTERS/Luke MacGregor (BRITAIN - Tags: TRANSPORT BUSINESS) 

A man and his daughter ride a bicycle along a street painted with the colors of the Brazilian soccer team, to celebrate the World Cup, at Tijuca neighbourhood in Rio de Janeiro June 11, 2010. In Brazil, where everything from the national Congress to the currency market stops in its tracks for Brazil games, it is safest to assume that nothing will be working as normal during the month-long tournament it has won a record five times. On the days Brazil's yellow-and-green shirted players take to the pitch in South Africa, banks have permission from the central bank to close early, the currency market will operate on shortened hours, and most government agencies will shut down. REUTERS/Sergio Moraes (BRAZIL - Tags: SPORT SOCCER SOCIETY TRANSPORT WORLD CUP) 

Navy cadets carry a giant St. George's ribbon (300 meters, or 984 feet, in length and 3 meters, or 10 feet, in width) to mark the upcoming 65th anniversary of the victory over Nazi Germany in 1945 in the Black Sea port of Sevastopol May 6, 2010. St. George's ribbon, part of the honorable Order of St. George, is now one of the most respected symbols of military valour in CIS countries. The black and orange stripes symbolize smoke and fire. REUTERS/Gleb Garanich (UKRAINE - Tags: MILITARY ANNIVERSARY IMAGES OF THE DAY) 

Women wearing traditional Sevillana dresses shelter from the rain as they take part in the April fair in Seville, April 21, 2010. The fair runs until April 25. REUTERS/Javier Barbancho (SPAIN - Tags: SOCIETY) 

A white tiger from China yawns inside a cage at Colombo's Zoological Gardens March 2, 2010. Officials say a pair of tigers were brought from China to show the friendship between the two countries. REUTERS/Dinuka Liyanawatte (SRI LANKA - Tags: ANIMALS POLITICS) 

Zebras stand inside a Kenya Wildlife Service (KWS) truck at the Soysambu Conservancy, 25 km from the Rift Valley town of Nakuru, February 10, 2010. KWS started the first phase capture of 7000 wild animals to restock Amboseli National Park. The restocking of Amboseli has been necessitated by last year?s prolonged drought that killed thousands of zebras and wildebeests in the park as well as the local community?s livestock. REUTERS/Thomas Mukoya (KENYA - Tags: ANIMALS) 

Students wear costumes inspired by nature at a parade during "Caracol 2010", a local version of Mardi Gras, along Makati, the financial district of Manila January 24, 2010. Caracol is part of the city government's commitment to conserve the environment and natural resources. REUTERS/Cheryl Ravelo (PHILIPPINES - Tags: SOCIETY) 

Dogs, one of them dyed to look like a tiger, are displayed for sale on a street in Nanjing, Jiangsu province January 7, 2010. According to the Chinese lunar calendar, the year of the tiger begins on February 14, 2010. REUTERS/Sean Yong(CHINA - Tags: ANIMALS SOCIETY) 

Dogs, one of them dyed to look like a tiger, are displayed for sale on a street in Nanjing, Jiangsu province January 7, 2010. According to the Chinese lunar calendar, the year of the tiger begins on February 14, 2010. REUTERS/Sean Yong(CHINA - Tags: ANIMALS SOCIETY) 

Two dyed donkeys stand at Marah Land zoo in Gaza City October 8, 2009. Two white donkeys dyed with black stripes delighted Palestinian kids at a small Gaza zoo on Thursday who had never seen a zebra in the flesh. A genuine zebra would have been too expensive to bring into Israel-blockaded Gaza via the smuggling tunnels under the border with Egypt, said zoo owner Mohammed Bargouthi. REUTERS/Mohammed Salem (GAZA SOCIETY ENVIRONMENT ANIMALS) 

Girondins Bordeaux's supporters wave and look out from underneath their team colours during their French Ligue 1 soccer match against Nice at the Chaban-Delmas stadium in Bordeaux August 23, 2009. REUTERS/Olivier Pon (FRANCE SPORT SOCCER)