A Chimpanzee is seen with funny expressions at Hanover Zoo on September 27, 2013 in Hanover, Germany. (Photo by Barcroft Media)

Opossums on their mothers back at a game reserve in Central Minnesota, USA, on September 2, 2013. (Photo by Caters News Agency)

Swedish brown bears “Fred” and “Frode” play in the snow on January 30, 2014 at the Natur- und Umweltpark (NUP) animal park in Guestrow, northeastern Germany. Despite of icy temperatures, the bear brothers took a break from their winter rest. (Photo by Bernd Wuestneck/AFP Photo/DPA)

This picture taken on January 1, 2014 shows giant panda “Li Li” sleeping on a tree in Hangzhou Wild Animal World in Hangzhou, east China's Zhejiang province. Giant pandas, notorious for their low s*x drive, are among the world's most endangered animals. Fewer than 1,600 pandas remain in the wild, mainly in China's Sichuan province, with a further 300 in captivity around the world. (Photo by AFP Photo)

A red fox sits in front of a Eurofighter Typhoon combat jet on the grounds of the 2014 ILA Berlin Air Show, in Selchow near Schoenefeld, Germany, Thursday, May 15, 2014. The International Aviation and Aerospace Exhibition ILA will take place from May 20 until May 25, 2014. (Photo by Patrick Pleul/AP Photo/DPA)

Alisa, 10, gets a kiss from one of the wolves her family tamed in the village of Zacherevye, Belarus, on August 17, 2014. (Photo by Sergei Gapon/AFP Photo)

Baloo (R), a North American Black Bear, rubs snouts with his companion Shere Hkhan, a Bengal tiger, inside their shared enclosure at Noah's Ark animal sanctuary in Locust Grove, Georgia, USA, 28 August 2014. According to the facility, the pair and a lion named Leo, were confiscated at a young age from a drug dealer's basement in Atlanta, Georgia. Noah's Ark cares for about 100 different species of animals on a 250 acre farm since 1990. (Photo by Erik S. Lesser/EPA)

An employee feeds a one-week-old coati cub with a bottle of milk at the Royev Ruchey zoo in the suburbs of Krasnoyarsk, Siberia, October 10, 2014. The mother of three cubs refused to nurse them, according to zoo employees. (Photo by Ilya Naymushin/Reuters)