Humanoid robot bartender “Carl” interacts with guests at the Robots Bar and Lounge in the eastern German town of Ilmenau, July 26, 2013. “Carl”, developed and built by mechatronics engineer Ben Schaefer who runs a company for humanoid robots, prepares spirits for the mixing of cocktails and is able to interact with customers in small conversations. (Photo by Fabrizio Bensch/Reuters)

A man prepares his kite to fly during an international kite festival in Alcochete, near Lisbon, Portugal, Sunday, June 28, 2015. Teams from Spain, US, Britain, Italy, France and Portugal performed with their kites during two days on the 13th edition of the event. (Photo by Francisco Seco/AP Photo)

A passenger aircraft passes over a residential house as it prepares to land at London Heathrow Airport in west London on October 17, 2016. Britain's government is considering whether to approve a third runway at Heathrow or expand air capacity in southeast England at another airport such as London Gatwick. (Photo by Daniel Leal-Olivas/AFP Photo)

An Israeli teenager crawls through mud as he participates in an annual combat fitness training competition, as part of his preparations ahead of his compulsory army service, near Kibbutz Yakum, central Israel February 19, 2016. (Photo by Baz Ratner/Reuters)

Local villagers prepare to bury the body of elephant Hemantha during a religious ceremony at a Buddhist temple in Colombo March 15, 2016. Elephant Hemantha, which died from injuries to its feet, was under medical treatment for the last six months. The elephant used to march at street parades during festivals held by the temple. Elephant Hemantha died at age 23. Wild elephants have long lifespans, reaching 60–70 years of age. (Photo by Dinuka Liyanawatte/Reuters)

Polar bears prepare to feast on the remains of a bowhead whale, harvested legally by whalers during their annual subsistence hunt, just outside the Inupiat village of Kaktovik, Alaska, USA, 10 September 2017. As climate change shrinks their natural habitat, polar bears are turning Kaktovik into their very own sanctuary city. (Photo by Jim Lo Scalzo/EPA/EFE)

Workers adjust rails at the bed of a drained area of a lake used for the production of salt at the Sasyk-Sivash lake near the city of Yevpatoria, Crimea, September 25, 2015. The area has a long tradition of salt production, prepared from salt flats flooded with water from the Black Sea. (Photo by Pavel Rebrov/Reuters)

Campers set structures on fire in preparation of the Army Corp's 2pm deadline to leave the Oceti Sakowin protest camp on February 22, 2017 in Cannon Ball, North Dakota. Activists and protesters have occupied the Standing Rock Sioux reservation for months in opposotion to the completion of the Dakota Access Pipeline. (Photo by Stephen Yang/Getty Images)