Students pose for a pictures taken by their friends during spring break on the beach in the resort city of Cancun, Mexico, February 27, 2009. (Photo by Israel Leal/AP Photo)

A “creuseur”, or digger, a plastic lantern on his head, readies to enter a copper and cobalt mine in Kawama, Democratic Republic of Congo on June 8, 2016. Cobalt is used in the batteries for electric cars and mobile phones. Working conditions are dangerous, often with no safety equipment or structural support for the tunnels. The diggers say they are paid on average US$2-3/day. (Photo by Michael Robinson Chavez/The Washington Post)

A robot Ecce by the Robot studio is pictured at the world's largest industrial technology fair, the Hannover Messe, in Hanover April 13, 2015. (Photo by Wolfgang Rattay/Reuters)

First prize. Taken over Bali Barat National Park, Denpasar, Bali. Made with a GoPro Hero 2 camera. (Photo by Capungaero)

Israeli illusionist and endurance artist Hezi Dean performs a purported levitation trick in Tel Aviv March 22, 2015. Dean on Sunday began what he calls a “24-hour levitation” on the outside of a Tel Aviv building. (Photo by Baz Ratner/Reuters)

An oversized, prehistoric praying mantis wreaks havoc in a freeway underpass as it overturns cars and trucks, in a film still from “The Deadly Mantis”, directed by Nathan Juran, 1957. (Photo by Universal Pictures/Courtesy of Getty Images)