This picture taken on March 21, 2015 shows a couple kissing in front of blooming cherry blossoms in Wuhan in central China's Hubei province. The cherry blossoms, now in full bloom, attracted tens of thousands of visitors, local media reported. (Photo by AFP Photo/Stringer)

In this Tuesday, March 12, 2019 photo, a visitor takes part in an immersive experience showing visitors how dogs see from inside the head of a dog at the California Science Center in Los Angeles. A new exhibit at a Los Angeles museum examines the relationship between dogs and humans and explores why the two species seem to think so much alike and get along so well. “Dogs! A Science Tail” opens Saturday, March 16, 2019, at the California Science Center. (Photo by Richard Vogel/AP Photo)

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 picture made available on 17 September 2014 shows extreme athletes resting in hammocks on webbings stretched between rocks during the International Highline Meeting in Monte Piana, near Misurina, in the northern Italian Alps, Italy, 08 September 2014. (Photo by Balazs Mohai/EPA)

Female Chimpanzee “Fifi” eats carrots as she sits in her enclosure at Taronga Zoo on her 60th birthday May 21, 2007 in Sydney, Australia. Fifi is the oldest of the Zoo's chimp population, which consists of 19 individuals. (Photo by Ian Waldie/Getty Images)

(L-R) Actors Oscar Sinela, Luis Fernandez, Ursula Corbero, Amaia Salamanca, Maxi Iglesias and Alba Ribas attend “XP3D” premiere at the Callao cinema on December 27, 2011 in Madrid, Spain. (Photo by Carlos Alvarez/Getty Images)

Afghan children play on the remains of a Soviet-era armored personnel carrier on the outskirts of Jalalabad on February 15, 2016. Soviet troops withdrew from Afghanistan on February 15, 1989, after ten years of fighting against Mujahidin militiamen. (Photo by Noorullah Shirzada/AFP Photo)

Cara Delevingne and Kate Moss attend the Burberry Prorsum show during London Fashion Week Spring Summer 2015 on September 15, 2014 in London, England. (Photo by Anthony Harvey/Getty Images)