Tanzania, 1964. A touching moment between primatologist and National Geographic grantee Jane Goodall and young chimpanzee Flint at Tanzania's Gombe Stream Reserve. (Photo by Hugo van Lawick via National Geographic)

Coca growers chew coca leaves during a celebration for the reincorporation of Bolivia to the UN Convention Against Illicit Traffic in Narcotic Drugs in La Paz on January 14, 2013. “The coca leaf is not any more seen as cocaine (...), it is a victory of our identity” said Bolivian President Evo Morales. (Photo by Jorge Bernal/AFP Photo)

Pantless people stand on a subway platform on January 13, 2013 in New York City. Thousands of people participated in the 12th annual No Pants Subway Ride, organized by New York City prank collective Improv Everywhere. During the afternoon winter event, participants boarded separate subway stops and removed their pants, pretending that they did not know each other. The event, refered to as a “celebration of silliness” is designed to make fellow subway riders laugh and smile. (Photo by Timothy A. Clary/AFP Photo)