In this April 4, 2017 photo, Zoologist Martha Llanes caresses baby chimpanzee Anuma II, left, while Ada hangs on to her leg, at Llanes' apartment in Havana, Cuba. She has forgiven them every transgression. It's hard to stay angry at a baby chimpanzee when it clambers up your leg and into your arms and plants a kiss on your cheek in a plea for forgiveness. (Photo by Ramon Espinosa/AP Photo)

A leg of a “diablito” frog (Oophaga sylvatica) is photographed in a laboratory at a laboratory in the zoo of Cali, Colombia, on July 19, 2019. Colombia is the second country with the largest number of amphibians in the world after Brazil. More than 40% of amphibian species worldwide are in danger of extinction. (Photo by Luis Robayo/AFP Photo)

An image captured by Jasmine Vink, the winner of the wildlife and animal category and overall winner in Australian Photography’s 2018 Photographer of the Year competition. (Photo by Jasmine Vink/Australia's 2018 Photographer of the Year by Panasonic)

A man with blood on his shirt is evacuated from Brussels Airport in Zaventem, Belgium, on Tuesday, March 22, 2016. (Photo by Dirk Waem/Belga/Zuma Press/TNS)

Airmen and their Japanese dates “do” the town together, visiting the local points of interest. Almost every community in Japan has it's famous shrines and parks. Tachikawa boasts beautiful environment. Girls are wearing western dress, May 1952. (Photo by National Archives and Records Administration)

“Aurora Hunters”. Photographers taking part in a photography tour on the Lofoten Islands in Norway, pull over on the side of the road to take a photo of their first ever Aurora Borealis after spotting it from their tour bus. Photo location: Rystad, Lofoten Islands, Norway. (Photo and caption by Mark Gee/National Geographic Photo Contest)

U.S. President elect Barack Obama kisses his wife Michelle as Vice-President elect Joe Biden (right) embraces his wife Jill after Obama gave his victory speech during an election night gathering in Grant Park on November 4, 2008 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)

The homemade Airbus A320 jet plane made by Chinese farmer Zhu Yue is being built at an open space in Kaiyuan city, northeast China's Liaoning province on February 4, 2018. (Photo by Imaginechina/Rex Features/Shutterstock)