“Slow”. A calm cow in the messy streets of Jodhpur. Photo location: India. (Photo and caption by Matthias Troeger/National Geographic Photo Contest)

Hot air balloons fly over the sky in Chiang Mai province, northern Thailand, December 6, 2014. The two-day International Balloon festival 2014 featuring balloon pilots from Germany, Spain, Netherlands, Britain, and Czech Republic is held on December 06-07 2014 to celebrate Thai King Bhumibol Adulyadej's 87th birthday and also aimed to promote the tourism industry in Chiang Mai northern city. (Photo by Pongmanat Tasiri/EPA)

A Filipino worker arranges roasted pigs which they sell in suburban Quezon city, Philippines on Tuesday, December 23, 2014. Roasted pig is popular during Filipino celebrations and traditionally served during a Christmas eve dinner called “Noche Buena” in this predominantly Roman Catholic nation. (Photo by Aaron Favila/AP Photo)

An Afghan woman fills containers with water near her temporary shelter at an internally displaced person's (IDP) camp on the outskirts of Herat, Afghanistan, January 21, 2015. Dozens of families are living in temporary shelters even in harsh winters and most depend on aid distributions by the United Nations High Commissioner for Refugees (UNHCR). (Photo by Jalil Rezayee/EPA)

Jiff with Playboy Playmates arrives at the Playboy Super Bowl XLIX Party on Friday, January 30, 2015 in Scottsdale, Ariz. (Photo by Omar Vega/Invision/AP Photo)

A Muslim man carries holy incensed smoke through a pedestrian subway in Mumbai, India, May 13, 2016. (Photo by Danish Siddiqui/Reuters)

A Selkirk Rex cat is one of more than 400 breeds of cats being presented at the World Cat Federation two-day show in Dortmund, Germany, on April 21, 2013. (Photo by Frank Augstein/Associated Press)

Zhang Jinduo's wife tries on a self-made racing car on the outskirts of Shenyang, Liaoning province May 10, 2008. Zhang, the 53-year-old local farmer made the racing car with the help of his son who is a car mechanic. The car is equipped with a rear-mounted motorcycle engine and can achieve 60-80 km per hour, according to local media. (Photo by Reuters/Stringer)