German flying ace Baron Manfred von Richthofen (1892–1918) also known as The Red Baron with his dog Moritz, circa 1916.

A Tamil devotee prays during the Thai Pongal harvest festival at a temple in Colombo January 15, 2016.The Tamil festival of Thai Pongal is a thanksgiving ceremony in which the farmers thank the spirits of nature, the sun and the farm animals for their assistance in providing a successful harvest. (Photo by Dinuka Liyanawatte/Reuters)

A clothing shop displays its merchandise in the rebel-controlled city of Idlib, Syria November 7, 2015. (Photo by Ammar Abdullah/Reuters)

Natalia Arango works with her mine detector in a zone of landmines planted by rebels groups near Sonson in Antioquia province, November 19, 2015. Women's work takes on a nontraditional meaning for fifteen Colombian women who work to rid the Antioquia Mountains of deadly landmines as the country edges closer to a peace agreement with Marxist rebels to end over a decade of conflict which has claimed 220,000 lives. (Photo by Fredy Builes/Reuters)

Members of the Palestinian Hamas security forces show their skills as they take part in a graduation ceremony in Gaza City on January 22, 2017. (Photo by Mahmud Hams/AFP Photo)

Members of an American landing party assist troops whose landing craft was sunk by enemy fire off Omaha beach, near Colleville sur Mer, France, June 6, 1944. REUTERS/Weintraub/US National Archives

Chinese military medics take part in a parade commemorating the 70th anniversary of Japan's surrender during World War II held in front of Tiananmen Gate in Beijing, Thursday, September 3, 2015. (Photo by Ng Han Guan/AP Photo)

“Tough Times for Orangutans”. Nature, first prize stories. Tim Laman, USA. Location: West Kalimantan, Indonesia. A Bornean orangutan climbs over 30 meters up a tree in the rain forest of Gunung Palung National Park, West Kalimantan, Indonesia, August 12, 2015. The lives of wild orangutans are brought to light. Threats to these orangutans from fires, the illegal animal trade and loss of habitat due to deforestation have resulted in many orphan orangutans ending up at rehabilitation centers. (Photo by Tim Laman/World Press Photo Contest)