In this photo taken Friday, September 4, 2015, tourists Sarah and John Scott from Worcester, England, take a step back as a male silverback mountain gorilla from the family of mountain gorillas named Amahoro, which means “peace” in the Rwandan language, unexpectedly steps out from the bush to cross their path in the dense forest on the slopes of Mount Bisoke volcano in Volcanoes National Park, northern Rwanda. Deep in Rwanda's steep-sloped forest, increasing numbers of tourists are heading to see the mountain gorillas, a subspecies whose total population is an estimated 900 and who also live in neighboring Uganda and Congo, fueling an industry seen as key to the welfare of the critically endangered species as well as Rwanda's economy. (Photo by Ben Curtis/AP Photo)

A woman poses for pictures with skulls made of cardboard placed on an altar next to the San Francisco church in Mexico City during the celebration of All Souls Day on November 2, 2015. (Photo by Yuri Cortez/AFP Photo)

A newborn grey seal pup is tended by its mother at Donna Nook, a nature reserve on the county’s coastline managed by Lincolnshire Wildlife Trust in Lincolnshire, UK on November 23, 2015. (Photo by David Tipling/Rex Shutterstock)

People walk along a street with long-tailed macaques in Lopburi, north of Bangkok November 29, 2015. (Photo by Jorge Silva/Reuters)

An injured boy who is undergoing surgery, after he was injured in what activists said was an airstrike by forces loyal to Syria's president Bashar al-Assad, rests inside a field hospital in the Douma neighborhood of Damascus, Syria December 5, 2015. Douma in Syria, an area controlled by rebels fighting to topple President Bashar al-Assad, has been shelled continuously for the past three years. The injured are taken to basements and shelters transformed into field hospitals run by medical staff who have stayed in the battered neighbourhood of Damascus. (Photo by Bassam Khabieh/Reuters)

A brick factory workers stack bricks on carts in Dhaka, Bangladesh, January 9, 2019. (Photo by Mohammad Ponir Hossain/Reuters)

Shaymaa Ismaa’eel, a 24-year-old Muslim woman passes by a group of angry protesters at an Islamic conference in Washington, DC on April 21, 2019. In response, she crouched in front of them and flashed a peace sign. The photo, posted on Instagram, prompted an outpouring of support. (Photo by Shaymaa Ismaa'eel/Instagram)

Parade goers during Brighton Pride Parade on August 03, 2019 in Brighton, England. Tens of thousands of revellers dressed in rainbow colours and elaborate costumes and descended on the seaside city to ask for equality for all. (Photo by Tristan Fewings/Getty Images)