Pakistani Rangers (black) and Indian Border Security Force personnel (brown) perform perform during the daily beating of the retreat ceremony at the India- Pakistan Wagah Border Post, some 35 kms west of Amritsar on August 14, 2017. Pakistan celebrates its independence on August 14, one day before India' s independence day on August 15. (Photo by Narinder Nanu/AFP Photo)

A ranger of Kenya Wildlife Services (KWS) tries to cover the eyes of 2.5-year-old female Southern white rhino, Elia, to calm down after being shot a tranquilizer from a helicopter during Kenya Wildlife Services (KWS) rhino ear notching exercise for identification at Meru National Park, 350 km from Nairobi, Kenya, on April 5, 2018. (Photo by Yasuyoshi Chiba/AFP Photo)

Woman on swings attached to a float during the Sexual Freedom Parade, part of Naughty in N'awlins held in New Orleans, Louisiana, Wednesday July 5th, 2017. These are the photos from inside the world’s largest swinging convention for couples. The exclusive images reveal the unlikely couples who like to engage in sexual relations with other people besides their partners – and show that swinging is more ‘normal’ than you think. (Photo by Mathew Growcoot/News Dog Media)

A bonnet macaque sits on consecrated idols of snakes as it drinks milk offered by a devotee during the Hindu festival of Nag Panchami, which is celebrated by worshipping snakes to honour the serpent god, inside a temple on the outskirts of Bengaluru, India, July 27, 2017. (Photo by Abhishek N. Chinnappa/Reuters)

A Hindu priest waits to perform prayers next to Tejas, India's first locally-built Light Combat Aircraft (LCA), before its induction into the Indian Air Force at the Hindustan Aeronautics Limited (HAL) Airport in Bengaluru, India, July 1, 2016. (Photo by Abhishek N. Chinnappa/Reuters)

Two brave contestants take part in the World Gravy Wrestling Championships at the Rose 'n Bowl in Stacksteads, Lancashire, England on August 27 2018. Contestants must wrestle in the gravy for 2 minutes, points are scored for fancy dress, comedy effect, entertainment and wrestling ability. The event is held to raise funds for the East Lancashire Hospice and competitors nominated charities. (Photo by The Mercury Press)

Spectators cheer as the United Launch Alliance Delta 4-Heavy rocket, with NASA's Orion spacecraft mounted atop, lifts off from the Air Force Station, December 5, 2014, in Cape Canaveral, Fla. (Photo by Smiley N. Pool/AP Photo/Houston Chronicle)