A replica of pre-historic drawings showing horses, rhinoceros and aurochs is seen on a wall during a press visit at the site of the Cavern of Pont-d'Arc project in Vallon Pont d'Arc April 8, 2015. The Cavern of Pont-d'Arc project is a replica of the pre-historic Decorated Cave of Pont-d'Arc known as Grotte Chauvet, in Vallon Pont-d'Arc in the Ardeche region, containing the world's earliest known art which was recently named a UNESCO World Heritage site. The facsimile cavern, which condenses some 8000m² of the original site into 3000m², will display faithful reproductions of paintings and engravings and will be inaugurated on April 10 and will open to the public on April 25. (Photo by Robert Pratta/Reuters)

A man rows a boat on the Dal Lake as a woman holds an umbrella during snowfall in Srinagar February 19, 2015. (Photo by Danish Ismail/Reuters)

Yang Juan, an employee at Goopal Group, takes a nap in her seat after lunch, in Beijing, China, April 21, 2016. Office workers sleeping on the job is a common sight in China, where a surplus of cheap labour can lead to downtime at work. But in China's technology sector, where business is growing faster than many start-up firms can hire new staff, workers burn the midnight oil to meet deadlines and compete with their rivals. Some companies provide sleeping areas and beds for workers to rest during late nights. (Photo by Jason Lee/Reuters)

Carlos Cure holds packets of corn flour made in Colombia as he poses for a picture at a stall that sells food and staple items at a market in La Fria, Venezuela, June 2, 2016. (Photo by Carlos Garcia Rawlins/Reuters)

Tatiana Osorio, of Orlando, cries while giving blood at the OneBlood blood center near the mass shooting at a nightclub, June 13, 2016, in Orlando, Fla. Osorio lost three friends in the shooting. (Photo by David Goldman/AP Photo)

A human rainbow is created at a BASEOrlando coordinated event, “Orlando Strong Body Paint”, on Friday, June 17, 2016 in Orlando, Fl. The group created the rainbow, composed of volunteers numbering the same as that of the victims of the Pulse shooting, as a visual reminder of the amount of lives lost. (Photos by Amanda Voisard/The Washington Post)

The nearly four-week-old Tapir cub bathes on June 28, 2016 in Gondwanaland at the zoo in Leipzig, Saxony. (Photo by Jan Woitas/DPA)

A sniper of the French “Brigade d'Intervention” takes up his position at the top of the Arc de Triomphe during the annual Bastille Day military parade on the Champs-Elysees avenue in Paris on July 14, 2016. France holds annual Bastille Day military parade with troops from Australia and New Zealand as special guests among the 3,000 soldiers who will march up the Champs Elysees avenue. They will be accompanied by 200 vehicles with 85 aircraft flying overhead. (Photo by Stephane De Sakutin/AFP Photo)