A zoo keeper carries a pelican to move it to its winter enclosure at Dvur Kralove Zoo in Dvur Kralove nad Labem, Czech Republic on November 5, 2019. (Photo by David W. Cerny/Reuters)

Jack, a Lurcher from Dogs Trust Salisbury, walks past a window display of models in a Dogs Trust shop window in Salisbury, as part of a campaign to discourage the impulse buying of dogs ahead of Valentine's Day, on February 10, 2014. (Photo by Matt Alexander/PA Wire)

A chevrotain or mouse deer feeds in its enclosure at Zurich Zoo, Zurich, Switzerland, October 17, 2012. (Photo by Patrick B. Kraemer/AP)

Three prostitutes lean out of a window in Santiago, Chile, in an attempt to entice customers inside, circa 1950. (Photo by Three Lions/Getty Images)

Miniature pig “Nueffel” is walked in a park in Hanover, Germany, 14 April 2016. (Photo by Sebastian Gollnow/EPA)

Unsettled life in Europe failed to change the slow pace of life on the Isle of Capri, off Naples, Italy. Some of the socialites who have come there to relax enjoy an aquatic luncheon serviced in the cool Mediterranean, September 1, 1939. Swimming waiters push out the floating tables bearing meals which include wine and spaghetti. In the background are the rocks of Faraglioni. (Photo by Hamilton Wright/AP Photo)

A German special anti-tank gun is ready to fire during the army maneuvers in Silesia, Poland, on September 22, 1928. (Photo by AP Photo)

In this Tuesday, March 20, 2018 photo, a Vampire Bat drinks bovine blood in the Criaturas de la Noche (Creatures of the Night) Bat House, the Audubon Zoo's new night house in New Orleans. The various species are all from Central and South America, and the building's interior simulates an abandoned warehouse set up to protect Mayan artifacts during a dig. (Photo by Gerald Herbert/AP Photo)