A Kenya Wildlife Services (KWS) veterinarian and security personnel back away from a tranquilised black-Rhino calf August 30, 2017 after she appeared to prematurely overcome the sedative at the Nairobi National Park, during an identification-tagging excercise to ease quick identification of resident rhino during anti-poaching patrols. (Photo by Tony Karumba/AFP Photo)

An injured young woman is led away after an incident at Parsons Green underground tube station in west London on September 15, 2017. Police and ambulance services said they were responding to an “incident” at Parsons Green underground station in west London on Friday, following media reports of an explosion. A Metro. co. uk reporter at the scene was quoted by the paper as saying that a white container exploded on the train and passengers had suffered facial burns. (Photo by Luke MacGregor/Reuters)

Mercury and Maia, fueled and overhauled, are waiting in the Tay at Dundee, for favorable weather to start the flight to the Cape, a distance of 6,370 miles. The composite machine moored in the Tay River, at Dundee, on September 23, 1938. (Photo by AP Photo)

“Be prepared” is the motto of petite Doris Sherrell, vocalist and dancer with “Blackouts of 1942”. In the event of a bombing, the young lady had her social security number tattooed on one leg by artist Jack Julian, and address placed on the other limb for means of identification in Los Angeles, September 29, 1942. (Photo by AP Photo)

Police detain an alleged thief in Lagos' Tafawa Balewa Square where the official People's Democratic Party (PDP) opposition party is holding a rally on February 12, 2019. Nigerians will cast their ballots on February 16 in presidential and legislative elections. The presidential contest will see incumbent Muhammadu Buhari seek to win a second four-year term against former vice president Atiku Abubakar in what is expected to be a close race. (Photo by Luis Tato/AFP Photo)

This picture taken on January 3, 2019 shows a Vietnamese woman collecting incense sticks in a courtyard in the village of Quang Phu Cau on the outskirts of Hanoi. In Vietnam's “incense village”, hundreds of workers are hard at work dying, drying and whittling down bamboo bark to make the fragrant sticks ahead of the busy lunar new year holiday. (Photo by Manan Vatsyayana/AFP Photo)

A mahout splashes water on his elephant on a hot summer day in Ahmedabad, India on April 8, 2019. (Photo by Amit Dave/Reuters)

People dressed in period costumes take part in the “Fetes Galantes” fancy dress evening at the “galerie des glaces” in the Chateau de Versailles, France on May 27, 2019. (Photo by Ludovic Marin/AFP Photo)