A zookeeper feeds a hippopotamus with a watermelon in its enclosure in Belgrade's zoo, Serbia, July 20, 2015. Temperatures in Serbia have risen up to 40 degrees Celsius (104 degrees Fahrenheit), according to official meteorological data. (Photo by Marko Djurica/Reuters)

Andy Goldfarb, a staff biologist at the Point Defiance Zoo & Aquarium, plays with one of the four clouded leopard cubs currently at the zoo Friday, June 5, 2015 in Tacoma, Wash. The quadruplets were born on May 12, 2015 and now weigh about 1.7 lbs. each. Friday was their first official day on display for public viewing, usually during their every-four-hours bottle-feeding sessions, which were started after the cubs' mother did not show enough interest in continuing to nurse them. (AP Photo/Ted S. Warren)

“Sniff out the Appenzell Cheese”. Alexander Hunter, 30, of Greenwich, Conn., took this photo in Appenzell, Switzerland, in September 2014. (Photo by Alexander Hunter)

“Touring the Koko-en Gardens adjacent to the Himeji castle was an unexpected highlight of our visit”, wrote Jeff Solar, 64, of Silver Spring, Md., about his trip to Japan. “The fall colors were outstanding and the gardens were both amazing and a bargain (just a few Yen added to the cost of the Himeji Castle admission)”. (Photo by Jeff Solar/2017 Washington Post Travel Photo Contest)

Japanese Macaque monkeys soak in the warmth of mountain hotsprings at Jigokudani Monkey Park, in Yamanouchi, central Japan, 19 January 2014. The Japanese Macaques (Macaca fuscata), also referred to as Snow Monkeys, live freely in this area that is covered by snow one third of the year. Jigokudani is the only known place in the world where monkeys bathe in natural hot springs. As a habit, they come down from the mountains where they spend the night and bath during the day. (Photo by Kimimasa Mayama/EPA)

“Car2go fleet is located throughout the greater downtown area and can be accessed on-demand or booked 24 hours in advance. The members may use the vehicle for as long as they like, without committing to a specific return time or return location”. – Wikipedia

Photo: A car2go employee shows how members can use a smartphone or iPad app to locate and reservec car2go vehicles March 22, 2012 in Washington, DC. Beginning March 24, car2go will offer the first free-floating car-sharing service in Washington and Portland, Oregon, where customers can use the smartphone app within the 34-square-mile “Home Area”. After paying a one-time $35 membership fee, drivers can then rent the Smart Fortwo vehicles by the minute, paying only for the time they use the vehicle, with discounted rates for hourly and daily use. (Photo by Chip Somodevilla/Getty Images)

Katie Francis, a member of the Difficult Access Team from Wiss, Janney, Elstner Associates, inspects a gargoyle while rapelling down one of the north tower on the west front of the National Cathedral while looking for damage from August's magnitude 5.8 earthquake and high winds from Hurricane Irene October 17, 2011 in Washington, DC. DAT members used cameras, cell phones and iPad computers to record places on the cathedral's west front where damage was apparent. (Photo by Chip Somodevilla/Getty Images)

A dog named Rama surfs a wave off Sydney's Palm Beach with its owner, Australian dog trainer and former surfing champion Chris de Aboitiz (not pictured), February 18, 2016. An Australian dog trainer and former surfing champion is using the discipline of surfing as a way of teaching owners to build healthy relationships with man's best friend. (Photo by Jason Reed/Reuters)