Two of 20 skulls to be taken possession of by a delegation from Namibia stand on display at a ceremony at Charite hospital on September 30, 2011 in Berlin, Germany. The skulls are from Herero and Nama tribespeople taken by German colonial forces between 1904 and 1908, when the Germans violently suppressed an uprising in what was then German Southwest Africa, which is today's Namibia, and in the process killed tens of thousand of Herero and Nama. German scientists at the time took the skulls back to Berlin to demonstrate the racial superiority of Europeans over black Africans. Many Namibians demand a formal apology from the German government. (Photo by Sean Gallup/Getty Images)

Patients from the Larco Herrera Psychiatric Hospital wear costumes in the likeness of the first governor and founder of the Inca civilization, Manco Capac, right, and his wife Mama Ocllo, during the hospital's Independence Day parade in Lima, Peru, Wednesday, July 22, 2015. The parade is held on the hospital's campus every year ahead of the Andean nation's official Independence Day celebrations on July 28. (Photo by Martin Mejia/AP Photo)

In this Wednesday, December 2, 2015 photo, Dr. Gal Kelmer, head of the department of large animals, unties a horse after its operation at the University's Koret School of Veterinary Medicine in Rishon Lezion, Israel. “Horses have an instinctive response of flight from danger”, Kelmer said. “The minute they wake up they start trying to stand and run, even if they don't have control of their limbs. So then they fall”. (Photo by Oded Balilty/AP Photo)

An animal rights protester demonstrates for the abolition of bull runs and bullfights, three days before the start of the famous running of the bulls San Fermin festival in Pamplona, northern Spain, July 4, 2015. (Photo by Eloy Alonso/Reuters)

A mahout removes the prosthetic from Motala, age 50, at the Friends of the Asian Elephant (FAE) elephant hospital in the Mae Yao National Reserve August 29, 2011 Lampang,Thailand. Motala lost a foot many years back after stepping on a land mine and now is on her third prosthetic, as they need to be changed according to the weight of the elephant. (Photo by Paula Bronstein/Getty Images)

Bride Fan Huixiang (front R), a 25-year-old cancer patient, receives flowers from nurses on her bed before her wedding ceremony at a hospital in Zhengzhou, Henan province November 17, 2014. Fan was diagnosed with late stage adenocarcinoma, a type of cancerous tumor, at her thoracic vertebra this June. She and her 24-year-old husband Yu Haining held their wedding ceremony at the hospital on Monday after five years of relationship, local media reported. (Photo by Reuters/China Daily)

Naked activists for animal rights, covered in fake blood, perform during a protest against the use of fur and leather, at Catalunya Square in Barcelona, Spain, December 16, 2018. (Photo by Albert Gea/Reuters)

With the help of some fake teeth and multiple exposures, New York AP photographer Eddie Adams' daughter Susan is transformed into a little ghoul on Halloween night, October 31, 1966. (Photo by Eddie Adams/AP Photo)