In this Saturday, June 24, 2017 file photo, Zeid Ali, 12, left, and Hodayfa Ali, 11, comfort each other after their house was hit and collapsed during fighting between Iraqi forces and Islamic State militants in Mosul, Iraq. The Ali cousins said some of their family members are still under the rubble. (Photo by Felipe Dana/AP Photo/File)

Ammunition airlift into besieged Khe Sanh, Operation Pegasus, April 1968. (Photo by Larry Burrows/AP Photo)

A Flame Skimmer or Firecracker Skimmer dragonfly (Libellula saturata) rests on a small branch in Topanga, California, USA, 18 June 2018. The Flame Skimmer dragonfly is found in the Western United States near ponds and creeks. (Photo by Mike Nelson/EPA/EFE)

New program of Munich's Krone Circus performed by two American artists “The Carmenas” during a press conference in Munich, Germany on January 10, 1962, while sitting in a coffee-house. (Photo by Heinrich Sanden Sr./AP Photo)

German Nazi leader Adolf Hitler (1889 - 1945) enjoys a quiet picnic between meetings, circa 1933. Picture 196 of a series of collectable images published in Germany during the Nazi period, entitled “Deutschland Erwacht” (Germany Awakes). (Photo by Heinrich Hoffmann/Hulton Archive/Getty Images)

Sulphur miners haul sulphur up an arduous path out of Indonesia’s Ijen volcano. The average carry out of the volcano is 70 kilograms per load per miner. The all-time record carry was 120 kilograms in one load. Extraordinary numbers given most of the miners only weigh around 55 kilograms. Ijen volcano, Indonesia, 2012. (Photo by Hugh Brown/South West News Service)

British tourist participates in a crab race at the annual Tobago Heritage Festival, at Buccoo Integrated Facility, in Tobago island, Trinidad and Tobago on July 29, 2018. (Photo by Andrea De Silva/EPA/EFE)

Model Daisy Lowe has been camouflaged into a wall of daisies by world-leading body paint artist Carolyn Roper, to showcase the Samsung QLED TV's Ambient Mode feature in London, United Kingdom on August 2, 2018. The work took eight hours to complete. (Photo by Matt Alexander/PA Wire)