Mark Dill and Brit Thacker practice acro-yoga as approximately 70,000 people from all over the world gather for the 30th annual Burning Man arts and music festival in the Black Rock Desert of Nevada, U.S. August 29, 2016. (Photo by Jim Urquhart/Reuters)

The Dora the Explorer balloon moves through Times Square during the Macy's Thanksgiving Day parade Thursday, November 23, 2006 in New York. (Photo by Frank Franklin II/AP Photo)

“Spa treatments don't stop with people. You won't see any aromatherapy candles around, but animals get massages, too, and it's become a regular service that many pet owners value as more than just glorified petting. Practitioners say massage can be a preventive measure for younger animals and rehabilitative for older ones by boosting flexibility, circulation and immunity”. – Terry Tang via The Associated Press. Here: in this November 6, 2014 photo, Shelah Barr of Happy Hounds Massage gives a massage to Dewie, 2, at the home of Laurie Ubben in San Francisco. (Photo by Jeff Chiu/AP Photo)

An abandoned tank left by Boko Haram, February 20, 2016, seen on the road to Michika, Nigeria – a town formerly occupied by the insurgents. On April 14, 2014, 300 schoolgirls in the Chibok village in Nigeria were kidnapped by the terrorist group, Boko Haram. Two years later, the majority of these girls are still missing. According to the Global Terrorism Index Report 2015, Boko Haram, which operates mainly in Nigeria, has become the most deadly terrorist group in the world. (Photo by Danielle Villasana)

A bunker at aformer Swiss artillery fortress called Heldsberg stands near the town of St. Margareten, Switzerland March 22, 2015. Heldsberg fortress, located on the Swiss-Austrian border near the River Rhine and Lake Constance was built from 1938 to 1940 and remained in military use until 1992. Since 1993 it is open to the public as Fortress Museum Heldsberg. (Photo by Arnd Wiegmann/Reuters)

Model Heidi Klum attends her 8th Annual Halloween Party at The Green Door on October 31, 2007 in Los Angeles, California. (Photo by Charley Gallay/Getty Images)