A curious leopard cub toys with a camera at MalaMala Game Reserve in Mpumalanga Province, South Africa. (Photo by Barcroft Media)

Local residents dressed in costumes perform during celebrations for the Malanka holiday in the village of Krasnoilsk in the Chernivtsi region of Ukraine, January 14, 2016. The Malanka traditional holiday is more popular in the western regions of the country and is also known as the Old New Year celebrated on January 13 and 14 – St. Basil's and St. Melania's Day, according to the old Julian calendar. During the celebrations, youngsters and adults wear traditional carnival costumes and masks, and visit local houses while singing carols, playing pranks or performing short plays. (Photo by Valentyn Ogirenko/Reuters)

ESA astronaut Samantha Cristoforetti on the International Space Station 3 February 2015 during her Futura mission. Samantha is living and working on the Station as part of the Expedition 42 crew. Picture released on February 10, 2015. (Photo by ESA/NASA)

Dancers perform on their way to attend a rally with former President Luiz Inacio Lula da Silva, “Lula”, supporting President Dilma Rousseff in the historic Lapa neighborhood on April 11, 2016 in Rio de Janeiro, Brazil. Brazil's congressional impeachment committee approved the motion to proceed with President Dilma Rousseff's impeachment process today. A full vote by the lower house of Congress on the impeachment is scheduled for Sunday to decide whether she will face trial. (Photo by Mario Tama/Getty Images)

An orphaned rhesus monkey and white dove that seemed to have lost its mate forged a special bond at the Neilingding Island-Futian National Nature Reserve in China. The monkey was born on the island but had strayed from its mother. Luckily, it was taken in by work staff in the protection center and became friends with the pigeon that had lingered there after possibly losing its mate. (Photo by CNImaging/Photoshot)

Morgan Miller carries her one-year-old daughter Mia Jennings in one arm as she shovels the stairs to her Springfield home with the other Sunday, January 13, 2019. Miller said she's learned how to do a lot of things while holding a baby in the last year. (Photo by Ted Schurter/The State Journal-Register via AP Photo)

Camera trapper Xavier Hubert-Brierre put this large mirror on the side of a road through the jungle in Gabon and left a camera there to record how the animals would respond to their own reflections. A silverback gorilla thought it was seeing another silverback and responded by trying to scare off the potential challenger… (Photo by Xavier Hubert-Brierre/Johns Hopkins University Press)

An Indian Runner duck searches for food on a snow-covered meadow in Aitrang, southern Germany, Wednesday. April 19, 2017. (Photo by Karl-Josef Hildenbrand/DPA via AP Photo)